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Rendiconti Lincei. Scienze Fisiche e Naturali
https://doi.org/10.1007/s12210-018-0741-4
REVIEW
Rita Levi‑Montalcini andher major contribution toneurobiology
PiergiorgioStrata1
Received: 1 August 2018 / Accepted: 25 September 2018
© Accademia Nazionale dei Lincei 2018
Abstract
In this paper, I shall illustrate the personality of Rita Levi-Montalcini and highlight how she first emerged within a prestig-
ious school, while under the direction of Giuseppe Levi, a most inspiring and stimulating figure. Between 1919 and 1938,
he created a rich environment capable of influencing the minds of innumerable students; among them, three future Nobel
Prize winners, Renato Dulbecco, Salvador Luria, and Rita Levi-Montalcini, who were companions in the same classroom. In
1938, due to the racial laws for the defence of the race, Luria and Levi-Montalcini were banned from entering the university
premises. In a small working space in her bedroom—“a minuscule laboratory not unlike a convent cell”—Levi-Montalcini,
supported by Levi, made a most outstanding discovery that opened a new chapter in neurobiology. Further collaborations with
Viktor Hamburger and Stanley Cohen led Levi-Montalcini to the discovery of the nerve growth factor (NGF): a remarkable
accomplishment which turned out to represent a milestone in the development of modern cell biology.
* Piergiorgio Strata
piergiorgio.strata@unito.it
https://www.piergiorgiostrata.net
1 Department ofNeuroscience, University ofTurin, Corso
Raffaello 30, 10125Turin, Italy
Rendiconti Lincei. Scienze Fisiche e Naturali
1 3
Graphical abstract
Hamburger
A
B
pioneer neuroblast
pioneer neuroblast
organizer tissu
e
organizer tissu
e
Levi-Montalcini
CD
Keywords Embryonic induction· Giuseppe Levi· Hans Spemann· Nerve growth factor (NGF)· Neuroembryology·
Stanley Cohen
1 Rita Levi‑Montalcini
What I am about to write is based not only on information
taken from Levi-Montalcini’s scientific publications, but
also from my personal contacts and from the numerous
articles she wrote that are rich in autobiographical data
(Levi-Montalcini 1975, 1982), and particularly from the
book entitled In praise of imperfection (Levi-Montalcini
1988). The story of the family environment, where she
grew up as a teenager is very enlightening in revealing the
profile of her personality that determined her future suc-
cess in science and society. For a historical perspective, it
is also important to mention the autobiographical report
of Rita’s close collaborator Viktor Hamburger (Hamburger
1989, 1993, 1996) and to report the views of qualified sci-
entists deeply involved in the same scientific field (Cowan
1981, 2001; Purves and Sanes 1987; Oppenheim 2001;
Chao 2010).
Let me start with the first time I met her. It was in the
summer of 1959 when I went to visit her in Turin at the
home, where she grew up in Corso Re Umberto 10. I was
writing my MD dissertation on avian behaviour and my Pro-
fessor, Giuseppe Moruzzi, organized the meeting, so that she
could enlighten me on the identification of some anatomical
lesions of the bird cerebral hemispheres that I had studied in
my thesis. When I started to call her “Professor” she stopped
me immediately and said: “I am Rita.” This was the way she
liked to be called by everyone throughout her life.
This happened at a time when the story that I am going
to illustrate on the discovery of a nerve growth factor had
its highest rate of success with a series of experiments per-
formed by Rita in collaboration with Stanley Cohen between
Rendiconti Lincei. Scienze Fisiche e Naturali
1 3
1952 and 1959. Rita forgot the purpose of my visit, and with
obvious enthusiasm, she described to me the accomplish-
ments she achieved in that period. I was impressed by the
possibility of performing a total sympathectomy with simple
subcutaneous injections of an antibody against the newly
discovered growth factor. The experiments appeared to me
very clear and easy to understand. Our talk went on until
I had to go and catch my train back to Pisa, where I was a
student. My mission had failed, but I went back home full of
enthusiasm from the meeting, an experience that contributed
to encouraging me to pursue my future activity in research.
2 The young Rita
Rita belonged to a Sephardic Jewish family. Her father,
Adamo Levi, had a strict Victorian view of life that at that
time was quite widespread in Europe. Accordingly, he saw
the role of the woman in society as a wife and as a mother
(“two X chromosomes in a Victorian climate,” as Rita herself
writes in her autobiography, Levi-Montalcini 1988). Thus,
he directed his daughter to a high school, where she was not
taught anything that would prepare her to cover important
professional roles in life nor any qualification that would
allow her to enter a medical faculty.
After completing high school, at age 17, for the next
3years, Rita felt she was in a dead end and unable to decide
her future. She was very attached to her mother, Adele Mon-
talcini, but not to her father with whom she had difficult
communications. Such a difficulty was often mentioned
by Rita and it is summarized in the dedication to her sister
Paola and to her father in her book In praise of imperfection
(1988): “To Paola and to the memory of our father whom she
adored while he lived and whom I loved and worshiped after
his death.” In fact, later, she acknowledged that her father,
more than her mother, had a crucial influence on her life
through both the inherited genes and his personality that she
admired for his tenacity, his energy and his intelligence, not
less than for his secular outlook and his Spinozan culture.
Following the illness and death of her governess, Gio-
vanna Bruatto, Rita was attracted by the idea of becoming
a medical doctor. She told her mother that she wanted to
study medicine and she was encouraged to speak with her
father about it. Finally, despite being discouraged by him,
she decided that she would not accept the subordinate role of
a woman and she convinced herself to give up the possibility
of the role of a wife. Therefore, after she had obtained the
necessary diploma in a private high school with the help
of two tutors, she was allowed to enrol in the Faculty of
Medicine and Surgery of the University of Turin (Fig.1).
This was the beginning of a sparkling career as a researcher
and in 1936 the Rector of the University, Silvio Pivano, con-
ferred the MD degree summa cum laude to Rita (Fig.2).
In 1938, she obtained the title of “volunteer assistant” in
the Nervous and Mental Illness Clinic (Clinica delle Malat-
tie Nervose e Mentali). However, following a Decree of
October 18, 1938, signed by the University Rector Azzo
Azzi (Fig.3), as a result of racial laws (Royal Decree Law,
September 5, 1938, n. 1390, Provisions for the defence of
race in the fascist school) (see also Fig.4), she had been
suspended from service from October 16. However, the same
provision, in Article 5, allowed students already enrolled
to complete their course of study, provided they were pass-
ing their exams successfully and on time, but without the
financial help of a scholarship. In this way, in 1939 Rita was
able to obtain the Specialist Diploma (Diploma di Specializ-
zazione) in Neuropathology and Psychiatry.
Thus, her scientific activity had begun during the second
year of medical school as an internal student at the Anatomy
Institute led by Giuseppe Levi. The Institute, as Rita under-
lined many times, was a pole of attraction for students, not
because of the fascination of the discipline, but for the out-
standing personality of its Director, renowned for his fame
as a scientist, but also for his unconcealed contempt for the
Fig. 1 Photo ID presented by Rita, as requested, together with the
application for enrollment in the first year of the Faculty of Medicine
and Surgery, dating back to October, 31, 1930. Courtesy of Historical
Archive of the University of Turin
Rendiconti Lincei. Scienze Fisiche e Naturali
1 3
Fig. 2 Fascist University Group, Majoring in Medicine and Surgery, Year 1935–36–XIV. The Faculty (first row): Quarelli, Bizzozzero, Vanzetti,
Micheli, Uffredduzzi, Allaria, Cova, Azzi, Negro. Rita is in row 6, number 4 from right. Courtesy of Piera Levi-Montalcini
Rendiconti Lincei. Scienze Fisiche e Naturali
1 3
fascist regime. This was the start of a fruitful connection
that would become very significant in the future of both. It
is interesting to note that the first work performed by Rita
under the guide of Levi was the object of her MD thesis in
July 1936. From the title Research on the invitro forma-
tion of collagen and reticular fibrils from explants of various
organs it is clear that she worked on the main topic of her
tutor, famous for his invitro studies. As we shall see, Rita
would draw her mentor’s interest to a new field.
3 Giuseppe Levi andhis school
Let us now give a brief profile of Giuseppe Levi (Figs.5
and 6): his personality, his intense and diversified cultural
experiences at international level, starting from when he was
a university student to his brilliant and multifaceted research
activity, to his moral rigor and his charming didactic activity.
All this led to the establishment of a true school as a forge
capable of forming qualified researchers in a state-of-the-art
institute with avant-garde technologies and, above all, of
stimulating young people to take up a research career. All
this happened at the Human Anatomy Institute (Istituto di
Anatomia Umana Normale) of the University of Turin under
the direction of this great master in the period 1919–1938.
Here, we have a magnificent example of how important it
is also to have different and frontier technologies to pursue
important achievements.
Levi was born in Trieste, but his academic activity
started in Florence. In 1889, at the age of 17, Levi entered
the Department of Medicine to work under the guidance
of Alessandro Lustig, Professor of General Pathology, who
had acquired rich international experiences at the University
of Vienna, where he had graduated in Medicine, and at the
Institute of Physiology at the University of Innsbruck as an
Assistant Professor. Levi’s contact with Lustig was the first
important step towards his scientific maturation.
During this period, Levi also came into contact with other
prominent personalities such as Filippo Bottazzi, Mario Car-
rara, Gino Galeotti, and Amedeo Herlitzka. After graduating
in 1895, he became Assistant to Eugenio Tanzi, and subse-
quently married his niece. The meeting with Ernesto Lugaro,
a pupil of Tanzi, was important, since Lugaro introduced
him to the field of neurobiology.
After these early contacts with great personalities,
Levi abandoned the clinical medicine to devote himself
entirely to experimental biology. Following a brief period
(1898–1899) in Berlin with Oscar Hertwig, he moved to
Florence (1899–1909) as Assistant to Giulio Chiarugi, Full
Professor of Normal Human Anatomy. Then, he moved to
the Stazione Zoologica in Neaples and to the University of
Sassari. In 1914, he was in Palermo, where he learned how
to make use of cell cultures for his research activity. During
the First World War, he was a volunteer physician, and in
1919, he finally held the chair of Normal Human Anatomy
in Turin until his retirement in 1948.
During the Turin period, he did not have an easy life. In
fact, his opposition to the fascist regime saw him among
those who signed the Manifesto of anti-fascist intellectuals
drawn up by Benedetto Croce in 1925. In addition, in 1926,
he sheltered Filippo Turati in his house, and in 1931, he
opposed the oath of allegiance to the regime, a position that
led him to being imprisoned together with his three sons
over the years 1934–1935. Finally, in 1938, he was sus-
pended from service due to the Royal Decree Law that also
banned Rita. During this period of ostracism, collaboration
with Rita began outside the institutions until 1943 when both
were hiding in Florence.
At the end of this troubled period, in 1945, he resumed
his activity, and on September 3, he delivered a remarkable
Fig. 3 Veto. THE RECTOR, according to items 3 and 6 of the R.D.
(Royal Decree) Law September 5, 1938-XVI, n. 1390; DECREES Dr
LEVI RITA, volunteer assistant in the Clinic of Nervous and Mental
Diseases of the R. [Royal] University of Turin, is suspended from ser-
vice, starting on October 16, 1938-XVI. Turin, October 18, 1938—
year XVI; THE RECTOR (Prof. Azzo Azzi. Courtesy of Historical
Archive of the University of Turin
Rendiconti Lincei. Scienze Fisiche e Naturali
1 3
opening lecture to his Human Anatomy course students enti-
tled La struttura della sostanza vivente (The structure of the
living matter) (Levi 1945). The lecture was dedicated to the
memory of Leone Ginzburg, his son-in-law, an anti-fascist
political activist, who was arrested at the age of 34, and
subjected to severe torture, which led to his death. The lec-
ture was also dedicated to the memory of all the university
persons who died defending their freedom. Between 1946
and 1950, he was also Director of the Centre for Studies on
Growth and Senescence (Centro di Studi sull’Accrescimento
e la Senescenza) of the National Research Council (CNR),
a centre that allowed him to obtain research funding, and in
1950 he launched a cell biology laboratory in São Paulo in
Brazil.
The internationally renowned School of Giuseppe Levi
had among its members a long series of great personalities
that were largely anchored in the neurological field in dif-
ferent disciplines: Tullio Terni, Luigi Bucciante, Rodolfo
Amprino, Oliviero Mario Olivo, Giovanni Godina, Angelo
Bairati, Cornelio Fazio and Edmondo Malan. Three students
received the Nobel Prize: Salvador Luria for genetic studies,
Renato Dulbecco for research on oncogenic viruses and Rita.
As we shall see, at least two techniques, which were
avant-garde at the time, were important to Rita’s suc-
cess. One was the staining of nerve fibres with silver salts
discovered by Camillo Golgi in 1873, later implemented
by Santiago Ramón y Cajal and refined by Fernando De
Castro. This method was critical for visualizing under the
microscope the state of the neuronal cell bodies and of
their nerve fibres during development. The second one was
the cell culture technology that Levi encountered when he
Fig. 4 Front page of Corriere della Sera, November 11, 1938,
announcing the approval of racial laws. The laws for the protection of
the race approved by the Council of the Ministers. Mixed weddings
are forbidden—the definition of “Jews”, the discriminations and the
annotation of civil status—the exclusion from employment in State,
parastatal and public interest agencies—rules concerning elementary
and middle schools and teachers
Fig. 5 Giuseppe Levi’s portrait donated to Rita Levi-Montalcini with
a dedication: “Alla sua valente collaboratrice e cara amica. 26 luglio
1943 G. Levi (to his talented collaborator and dear friend. July 26,
1943 G. Levi).” The day before the radio had announced the fall of
the fascist government. Courtesy of Piera Levi-Montalcini
Rendiconti Lincei. Scienze Fisiche e Naturali
1 3
was in Palermo, and that he now introduced to his institute
as an important facility focusing his pioneering research
on neural cells, mainly in collaboration with Hertha Meyer
(Levi and Meyer 1941). Meyer had been trained and had
worked in Germany, but when the Nazis seized power,
she moved to Italy. Subsequently, when racial persecution
became a serious problem in Italy, she moved to Brazil to
the most distinguished Biophysics Institute of the Univer-
sity of Rio de Janeiro, led by Carlos Chagas. Many years
later Rita visited this same institute and in collaboration
with Meyer she performed one of her most significant
experiments (Levi-Montalcini etal. 1954).
4 The dual team andthewar drama
We left Rita with her academic titles. However, following
the above-mentioned legislative measures she was not able
to enter the university premises and continue her studies.
Therefore, in March 1939 she accepted an invitation from
Prof. Lion Laruelle and continued her research activity at
the University of Brussels. Giuseppe Levi was already in
Belgium invited by Prof. Jean Firket to work in the Univer-
sity of Liège, where he was able to establish a cell culture
laboratory in collaboration with Maurice Chèvremont and
continue his research activity. At weekends Rita visited
Giuseppe Levi and the dual team was again in contact.
However, in September of the same year Poland was
occupied by the Germans and Hitler was threatening to
invade Belgium. Therefore, Rita returned to Italy for
Christmas. On June 10, 1940, Italy entered the Second
World War. She was worried by the political situation
and unsure of what to do, when Rodolfo Amprino, a bril-
liant member of the Levi School, encouraged her to set
up a small laboratory somewhere to continue her research
activity. She did so in a small working space in her bed-
room: “a minuscule laboratory not unlike a convent cell”
(Levi-Montalcini 1988). Levi, instead, remained in Bel-
gium until the summer of 1941 when he again joined
Rita in the new small laboratory. Once again they were
in contact.
However, following the heavy bombing of Turin by the
Anglo-American air forces in 1941 Rita left the city and
took refuge in the countryside near the town of Asti. In
1943 the situation deteriorated considerably. Following the
invasion of Italy by the German armed forces and the Ger-
man plan to send the Jews to concentration camps in Ger-
many, all of Rita’s family escaped to Florence living under
a false name until the end of the war, when they could
start a new life in Turin and Rita could plan to resume her
research activity.
5 Viktor Hamburger
The actual research of Rita and Giuseppe Levi together
began in 1941 in her homemade laboratory. Levi had read
an article published by Viktor Hamburger (1934) and in
1938 he gave it to Rita to read. She did so in a train during
a trip to a small village in the mountain with her friend
Guido. Here are her comments: “I was distractedly read-
ing an article Levi had given to me two years before. […]
For me, Hamburger’s limpid style and the rigor of his
analysis—in sharp contrast with those of previous authors
who had described the same phenomenon in amphibian
Fig. 6 Giuseppe Levi (left). Tempera on rigid panel by Ottavio Maz-
zonis, The ages of man, 1994, Institute of Anatomy of Turin. Cour-
tesy of Giacomo Giacobini
Rendiconti Lincei. Scienze Fisiche e Naturali
1 3
larvae—cast new light on the problem” (Levi-Montalcini
1988). To better appreciate the scientific achievements
made by Rita and Levi, it is worthwhile to outline the
scientific profile of Hamburger and his main conclusions
that inspired “new light” in Rita.
Hamburger was a world authority in the field of nervous
system development. He was born in Germany and after
Gymnasium (high school) he spent two summers in the
University of Heidelberg. Here he became interested in
developmental biology. Soon he moved to the Department
of Zoology at the University of Freiburg whose Director,
Hans Spemann, assembled an outstanding group of sci-
entists and with whom he obtained his PhD in 1925. The
title of his thesis was The relationship between nerve and
limb development, thus acquiring interest in neurogenesis
(see also Hamburger 1925). This contribution may be con-
sidered the starting point for the future investigations that
characterized the entire life of Hamburger and led to his
collaboration with Rita.
Spemann was awarded the Nobel Prize in 1935 for the
discovery of an “inductive factor” in embryology (Spe-
mann and Mangold 1924). Working on amphibian eggs,
along with Hilde Mangold, he demonstrated the exist-
ence of an area in the embryo which, when transplanted
into a still undifferentiated part of another unformed one,
induced the formation of a second embryo. In other words,
he obtained an embryo within an embryo. Therefore, he
postulated the existence of an “organizer”, the name he
gave to this region. Later, it has been assumed that several
territories are organizers of different regions of the brain.
These results inspired many of the embryology experi-
ments conducted in the rest of the century. The role of the
amphibian organizer has been identified subsequently in
embryos of fish, birds and mammals, including a specific
locus in the human embryo (Martinez Arias and Steventon
2018; Martyn etal. 2018; Pourquié 2018).
After short periods in Göttingen and Berlin, in 1927 Spe-
mann offered Hamburger a position as an instructor. This
allowed him to return to Freiburg. However, he was dream-
ing of visiting the United States and spending some time in
Chicago with Frank Lillie, a long-term friend and admirer of
Spemann and the author of a classic book on chick develop-
ment (Lillie 1908). Lillie (1903) had performed experiments
on chick embryos to ascertain whether a wing primordium
might regenerate after extirpation and later (Lillie 1904) he
had demonstrated that “the embryo of the chick possesses
no greater power of regeneration than the adult” (quoted in
Willier 1957).
In 1932 Hamburger obtained a Rockefeller fellowship to
work in Chicago for 1year (Fig.7), a period extended to
3years (1932–1935) when, in April 1933, the Nazis came
to power in Germany, and Hamburger received a letter from
the Rector of the University of Freiburg, Martin Heidegger,
announcing that he no longer had a research position in Ger-
many because of his Jewish ancestry.
Following this difficult period in 1934 he was offered a
position at the Washington University in St. Louis. He went
briefly back to Germany to bring his wife and daughter to
the United States and in 1935 he moved to the new place,
where he stayed for the rest of his life. He was Chairman of
the Department of Zoology from 1941 to 1966. He became
Professor Emeritus in 1969 and continued his laboratory
work until the mid-1980s.
6 Peripheral organizers forbrain structures
The work published by Hamburger in 1934 is the outcome
of the experimental results acquired mainly in Chicago and
the interpretation of the results reflects the culture of the
Spemann School. Many years before, the young Marian
Lydia Shorey, under the suggestion of Lillie, studied the
Fig. 7 Viktor Hamburger in 1933. Marine Biological Laboratory
Copeland-Bloom Photo Album, Marine Biological Laboratory
Archives. Licensed as Creative Commons Attribution-NonCommer-
cial-Share Alike 3.0 Unported https ://hpsre posit ory.asu.edu/handl
e/10776 /3264?show=full
Rendiconti Lincei. Scienze Fisiche e Naturali
1 3
problem of the correlation between the nervous system and
peripheral structures during development (Shorey 1909) and
this was the real beginning of a new field in embryology.
She removed the limb bud on one side of a chick embryo
and she found, both in the spinal ganglia and in the anterior
and posterior horns of the spinal cord, a reduced number of
cells. However, she found that “no degenerating fibres can
be observed when the extirpated areas are removed before
the nerves reach the region of the operation.” Therefore,
she concluded that “the defects which appear in the nerv-
ous system are not due to degeneration, but to the failure of
certain neuroblasts to develop.” This phenomenon is called
hypoplasia, which means deficient development.
In addition, she noticed that a complete destruction of
the muscles of a given somite did not lead to the complete
suppression of motor cells and motor fibres at this level of
the spinal cord, but their number was greatly reduced. How-
ever, she observed that the motor fibres were innervating
the muscles of the nearby located somite above or below
the lesion. Thus, she wrote that “it is safe to assume that all
are alike dependent on stimulation from end organs or the
products of the activities of the end organs, for differentia-
tion.” In conclusion, her results showed that the periphery is
essential for the developmental organization of the nervous
system. In a subsequent paper Shorey (1911) suggested that
“metabolic products” from the muscles that diffuse into the
lymph provide the stimulus that regulates the differentiation
of innervating neurons.
Lillie suggested to Hamburger that he should study the
mechanisms of such a relationship. First, by careful quan-
titative assessment at embryonic days 8–9, Hamburger
confirmed the previous results illustrated by Shorey on the
marked hypoplasia in the spinal cord and in the ganglia and
he found a quantitative relation to the degree of muscle
destruction. He also noted that when such a deletion was
radical it did not result in a complete lack of the anterior
horn, where about 40% of cells were still present (Ham-
burger 1934). Such a survival was not later confirmed by
Levi-Montalcini and Levi (1944). The interpretation offered
by Hamburger was that these neurons develop independently
of the periphery, while the remaining pool is under periph-
eral control. According to Ross Harrison (1907), embryonic
nerve cells send long projections out of the central nerv-
ous system and later they take contact with the appropriate
peripheral target. Hamburger assigned to these developing
neurons the role of “pioneers” to explore the size of the
peripheral field and to send back to the neural centres a
signal to recruit the appropriate number of central neurons
(retrograde recruitment hypothesis) (Fig.8). The remaining
central neuroblasts will degenerate. As to the nature of the
retrograde signal, he suggested that specific agents for the
sensory and the motor components originate in the periph-
eral site acting as organizers for brain structures.
This view was consistent with Spemann’s concept of
the “organizer”. In the absence of the periphery the neural
centres would go awry and everything would disappear.
In summary, it had been proposed that the developing
muscles and sensory devices produce two different and
specific factors that migrate backwards into their respec-
tive nerve centres, namely, the motor columns and spinal
ganglia, where they promote the maturation and govern
the development of these centres in a precise quantitative
manner. The results were good support for the hypothesis
Hamburger
A
B
pioneer neuroblast
pioneer neuroblast
organizer tissue
organizer tissue
Levi-Montalcini
C
D
Fig. 8 Role of the wing or limb bud on spinal neuron differentiation
and maturation. Above: The induction hypothesis by Hamburger.
Among a group of neuroblasts, a few of them (pioneers) send an
elongation towards the peripheral tissue organizer (a). Here they
pick up from the environment a substance that migrate retrogradely
(arrows) up to the spinal cord, thus inducing a differentiation and a
maturation of the same cell pool (b). Below: Chick embryo submit-
ted to the amputation of the peripheral bud of one side on day 3. The
figure on the left shows neurons of the spinal ganglion of the normal
side on day 15. The neurons show a high degree of differentiation and
maturation (c). The figure on the right side shows the neurons of the
ganglion of the amputated side, where numerous cells appear well
differentiated, but with clear signs of degeneration (d) (Levi-Montal-
cini and Levi 1944)
Rendiconti Lincei. Scienze Fisiche e Naturali
1 3
elaborated by Spemann that dominated for such a long
time.
7 A novel approach
To the eyes of a biologist the explanation proposed on the
basis of Spemann hypothesis was widely accepted and pos-
sibly had made Lillie, a Spemann admirer, happy. However,
to the eyes of Rita, the data represented a way to examine a
new paradigm in the study of the brain. Therefore, in col-
laboration with Levi from the spring of 1941 to the autumn
of 1942 she planned to repeat the experiments performed
by Hamburger. The results, published in 1942–1944 (see
below), signalled the beginning of a new chapter in neuro-
biology. The aim of the experiments was to observe directly
the developing cells and their elongations towards the
peripheral region during the developmental phase. This was
possible by visualizing the neurons by means of the silver
staining, a technological advantage not used by Hamburger.
Later, Rita would export the technique to the American lab
and Hamburger would acknowledge that she had brought a
very important instrument from Turin.
The primary question was to understand by which mecha-
nism the elimination of the limb causes a reduction of the
number of neurons that would normally provide its inner-
vation. The results demonstrated that in a chick embryo,
following the removal of the wing or the limb primordium,
neurons were able to proliferate to achieve full maturation
and to emit elongations toward the peripheral region and
reaching the proximity of the missing primordium. They
observed a neuron regression during the following days and,
starting at about 2weeks, the complete set of fully differ-
entiated neurons were gradually disappearing. In contrast
to what Hamburger postulated originally, the reduced cell
number following the bud removal was not a result of hypo-
plasia. It was the consequence of the death of fully differ-
entiated neurons and not of the failure of cell recruitment
from a pool of still uncommitted precursors (Fig.8). In other
words, it was a process of degeneration which had escaped
the attention of both Hamburger and Shorey. Rita and Levi
concluded that the central neurons develop and differentiate
in the absence of the primordium and that the regression of
the motor or sensory neurons depends on the impossibility
of establishing connections with the peripheral structures,
the muscles and the skin. Therefore, for neuron differen-
tiation there was no need of an early interaction with the
wing or the limb primordia and this ruled out their role as
inductive factors and the retrograde recruitment hypothesis.
Instead, it is the lack of a factor released from the primordia
that is simply needed for neuron survival. This hypothesis
was later confirmed during the collaboration between Rita
and Hamburger (Hamburger and Levi-Montalcini 1949).
At that time the results could not be published in Italy,
but the authors found space—in short format—in a jour-
nal published in Belgium (Levi-Montalcini and Levi 1942,
1943) and—more extensively, with an abstract in Latin—in
a Vatican journal (Levi-Montalcini and Levi 1944) (Fig.9).
The results, obtained in the most difficult environmental
conditions and in a homemade laboratory, are documented
by a rich and magnificent set of handmade illustrations. The
conclusions were in contrast to the hypothesis based on
the experiments by Spemann and Mangold (1924) and on
the interpretation that Hamburger gave for his experiments
(Hamburger 1934) on induction in neural development. They
should be considered a milestone in neurobiology. In addi-
tion, the paper opened a new window for future research in
the field. In this fruitful collaboration Rita found in Levi a
brilliant mentor and Levi found in Rita an acute and bright
mind with outstanding intellectual and technical capacities
able to move the main interest of her tutor into a new modern
and attractive field. In this outstanding series of revolution-
ary scientific achievements Rita revealed also a stigma of
tenacity and energy that she attributed the genes inherited
by the father.
At the end of the Second World War, Hamburger, Chair-
man of the Department of Zoology at the Washington Uni-
versity in St. Louis, became aware of the results of his Ital-
ian colleagues and he realized the importance of the critical
comments they had made about his discoveries. In the spring
of 1946 he wrote to Levi to have the young scientist in his
laboratory at the Washington University of St. Louis for a
period of 6months to discuss and clarify the different inter-
pretations of their respective experiments. On September
19, 1947, Rita began her 2-week trip on a Polish ship, the
Sobieski, to reach the place of the new adventure. Dulbecco
was on the same ship on his way to Bloomington, Indiana,
to collaborate with Luria. Rita remained at Washington Uni-
versity for 26years, a period that she recalled as the happiest
and most productive of her life. This period was in fact a
saga of revolutionary discoveries. The exodus of the three
brilliant Turin brains was the start of a heavy and unbalanced
flux of Italians which persists until the present day.
8 The new world
At this point of our story the role of Turin becomes of minor
importance. However, the subsequent scientific achieve-
ments gathered by Rita in the United States remain a won-
derful product of the Turin School of Giuseppe Levi. There
was a crucial point that divided the line of thought of Rita
and Hamburger (Fig.8). According to Rita, in the absence
of the limb or wing buds, the neuronal elements were able
to grow and to differentiate, but they were going to degener-
ate later when their axons arrived close to the missing bud.
Rendiconti Lincei. Scienze Fisiche e Naturali
1 3
This view was against the induction hypothesis. According
to Hamburger, in fact, the neurons were unable to differenti-
ate due to the lack of an induction mechanism.
Hamburger was interested in examining the effects of
limb ablation with Rita. Therefore, as soon as she reached
St. Louis the new team repeated the experiments that she
and Levi had performed in Turin. They demonstrated that
both motor neurons and the neurons of the sensory ganglia
were degenerating after removal of the peripheral buds. In
addition, they showed that after transplanting an additional
primordium in the embryo, the number of spinal neurons
increased. Therefore, they concluded that the periphery
provided the necessary conditions for both the completion
of axonal growth during development and the survival of
neurons (Hamburger and Levi-Montalcini 1949). Again,
these findings were against Spemann’s induction hypothesis.
According to Cowan (2001), these results on development
published by Rita and Hamburger in 1949 represent one of
the best works in the whole of neuroembryology.
In 1948, at the beginning of their collaboration, Ham-
burger showed Rita the results of a series of experiments
made by one of his former students, Elmer Bueker, who
had been working on the topic since 1943. Bueker (1948)
had implanted a fragment of a sarcoma on the walls of a
3-day chicken embryo. The student observed that in the
following days the sensory ganglia had increased in vol-
ume and some fibres of these ganglia elongated to reach
the inner region of the tumor. On the contrary, he did not
notice any elongation of the fibres of the motor neurons.
Bueker interpreted the results as the consequence of an
inductive action that the tumor exerted on the nerve cen-
tres, the same hypothetical inductive action exerted on the
spinal centres by the peripheral buds.
Rita and Hamburger (Levi-Montalcini and Ham-
burger 1951) repeated the experiment made by Bueker.
Using the technique of staining with silver salts that Rita
had imported from Turin, they were able to observe the
behaviour of the nerve fibres. The results confirmed what
Bueker had described. However, thanks to the staining of
the nerve fibres, it became clear that growing up inside the
tumor were not only the sensory fibres coming from the
spinal ganglia, but also fibres that came from the ganglia
of the sympathetic nervous system. It was also possible to
demonstrate that the new fibres entering the tumor did not
make contact with its cells: they were free nerve terminals.
These findings demonstrated for the first time the existence
Fig. 9 Front page with Latin abstract of the paper by Levi-Montalcini and Levi (1944)
Rendiconti Lincei. Scienze Fisiche e Naturali
1 3
of a diffusible agent released by the cells of the tumor into
the surrounding tissue.
Rita decided to place the sarcoma on the chorio-allan-
toic membrane that covers the embryo, thus eliminating
the direct contact between the embryo and the tumor. The
results were similar and against the retrograde recruitment
hypothesis previously postulated by Hamburger. Therefore,
the hypothesis of the induction factor and of an organizer
was once more not supported by the new experimental evi-
dence. It was evident that the tumor released a soluble factor
which, through the embryonic blood circulation, reached the
ganglion neurons (Levi-Montalcini 1952; Levi-Montalcini
and Hamburger 1953). These results are the birth certificates
of the nerve growth-promoting factor, which later became
known as NGF.
According to Cowan (2001), “There is a hint, however,
that Viktor was somewhat uneasy about Rita’s independent
report at the meeting of the NY Academy of Sciences, which
is referred to in a footnote on the second page of their 1953
paper: ‘A preliminary report of this work has appeared in
the Ann. N.Y. Acad. Sci. 55, 1952’.” Later Hamburger, in
one of his biographical papers (Hamburger 1989), stated
that he participated to the initial phase of the new topic
on the soluble factor. He realized that this was the begin-
ning of the story of the nerve growth factor, but he decided
to pursue other interests. His collaboration with Rita was
close to an end although Hamburger continued to fully sup-
port the investigations on this new frontier in his St. Louis
Department.
Several years later, however, Hamburger provided further
important contributions on the influence of the periphery in
the development of the spinal motor column (Hamburger
1958), the timing of cell death (Hamburger 1975), the out-
come of a supernumerary limb transplant, where it was
shown that it does not lead to an enhancement of cell prolif-
eration, but it reduces cell death (Hollyday and Hamburger
1976). In addition, using a radiolabelled NGF provided by
Ralph Bradshaw, he showed that NGF is taken up by sensory
nerves and transported in a retrograde direction to their cell
body in the spinal ganglia (Brunso-Bechtold and Hamburger
1979). He also provided the first good demonstration that the
administration of exogenous NGF to the developing chick is
able to reduce the naturally occurring cell death in the spinal
ganglia (Hamburger etal. 1981).
9 Rio de Janeiro andthe“golden halo”
Rita and Hamburger were aware of the fact that to continue
their fascinating story it was necessary to identify the nature
of the growth-promoting factors and their mechanisms of
action. They tried to see if chemical extracts of the tumor
injected into embryos could replicate the effects observed
after tumor transplantation. Rita (Levi-Montalcini 1988)
reported later that: “The persistent negative results led me
to resort to other techniques.” They realized that it would
be important to isolate and identify the factor. One possible
way was to use the culture technology which Rita had used
in Turin for her MD thesis under the supervision of Hertha
Meyer. She kept contacts with her and now she asked her
old friend to perform the experiments in her lab in Rio de
Janeiro. This plan was easier than to set up a new culture
facility in St. Louis. Hamburger was able to persuade the
Rockefeller Foundation to provide Rita with a travel grant to
stay in Rio for 3months. At the end of the summer of 1952,
on her way to Rio, Rita travelled to Italy to visit her family
and from there she went to Rio carrying with her, throughout
the whole journey, two white mice with transplanted sarco-
mas S180 and S37 hidden in her purse or her coat.
As soon as she was in Rio, sarcoma cells were grown in
a small dish, close, but not in contact, to the sympathetic
ganglia neurons. A fascinating picture appeared in front of
Rita. After only 24h of culture, thick bundles of sympa-
thetic fibres emerged radially from the ganglia, like a halo
(Fig.10). There was no doubt that a soluble factor produced
by the tumor was driving the fibre growth. Rita kept Ham-
burger informed of the spectacular results that she carefully
recorded by sending handmade outlines of the images. The
results of the experiments performed in Rio were soon pub-
lished (Levi-Montalcini etal. 1954). When back in St. Louis
she established a tissue culture facility which was necessary
to continue this line of investigation.
10 Stanley Cohen, anew entry
Hamburger and Rita realized that to identify the nature of the
newly discovered growth-promoting factor, it would be wise
to ask for help from a biochemist. The choice was Stanley
Cohen. He was born in Brooklyn in 1922. His parents were
both Russian Jewish emigrants who came to America in the
early 1900s. In his recollections of his life he writes: “Grow-
ing up in the streets of Brooklyn, I remember being interested
in how things worked: taking apart an old telephone and the
gears of my new 4-speed bicycle was most enjoyable. As a
biology major at Brooklyn College in 1945, I was fascinated
by embryology. How does an egg turn into a chicken or a
frog or a person? My only insight into the problem was the
thought that it was necessary to understand the chemical
reactions inside the egg and embryo and not simply observe
biological structures” (Cohen 2008). He continued his edu-
cation as a PhD student in the Department of Biochemistry
of the University of Michigan under Howard B. Lewis. Then
he moved to the Department of Pediatrics at the University
of Colorado and in 1952, with a fellowship of the American
Cancer Society, he went to the Department of Radiology of
Rendiconti Lincei. Scienze Fisiche e Naturali
1 3
the Washington University to work under the guidance of
Martin Kamen. As Cohen (2008) recalls: “Upon completion
of my fellowship, Dr. Kamen recommended me for a position
in the Zoology Department of Washington University in the
laboratory of Viktor Hamburger and Rita Levi-Montalcini.
This move was critical in determining the direction of my
research for the next 40-some odd years: the isolation, struc-
ture, and function of the first of the ‘growth factors’, nerve
growth factor (NGF) and epidermal growth factor (EGF).
[…] Neither Dr. Hamburger nor Dr. Levi-Montalcini were
biochemists so they went to several of Washington Univer-
sity’s departments looking for a biochemist ‘mad’ enough to
study this problem. […] It was a good combination; I knew
very little about neuroembryology, and they knew very lit-
tle about biochemistry so we interacted but never argued.”
Hamburger informed Rita, who was still in Rio. Mean-
while, he obtained additional funds from the Rockefeller
Foundation to support the new project. Rita answered that
Cohen seemed to be the right person. Later she would write
(Levi-Montalcini 1988): “I have often asked myself what
lucky star caused our paths to cross.”
When Rita was back in St. Louis she started collaborat-
ing with Cohen with the aim of identifying the mysterious
molecule. In a short time they obtained interesting results
that they published immediately. Cell-free homogenates of
the tumor developed on embryos reproduced in cultures of
sympathetic ganglia the effects observed in the experiments
performed in Rio. From this homogenate Cohen could iso-
late a molecule that appeared to have the characteristics of a
nucleoprotein, i.e., made by a protein bound to nucleic acids
(RNA, DNA). This still unknown substance was named
nerve growth-promoting factor. It marked the beginning of
the story of the nerve growth factor or NGF (Cohen etal.
1954).
Cohen, at a daily seminar, where he was presenting his
results, asked Arthur Kornberg, a future Nobel Laureate,
for advice on how to be sure that the factor isolated from
the sarcomas was a nucleoprotein and not a simple protein,
and if it were a nucleoprotein, how to see which of the two
components was the active one. Kornberg suggested using
a snake venom which was known to be rich in an enzyme
able to destroy the nucleic acid component. If the fluid was
still effective after the treatment, the protein would have
been responsible for the action. This proved to be the case.
The outcome of the new experiment was successful. After
some hours Rita observed a rich halo emerging from the
sympathetic ganglia in culture. In addition, now, a remark-
able serendipitous discovery had been made. In a control
experiment, where only the venom—but not the tumor—was
applied to the culture, a similar halo appeared. Thus, the
venom contained the same or a similar nerve growth-pro-
moting factor. The most important aspect of this discovery
was that: “The biological effects of the venom factor, tested
in tissue culture, are very similar to the effects produced
by a factor obtained from sarcoma 180. However, our most
purified venom preparations have a specific activity (on a
protein basis) approximately 1,000 times as high as our pur-
est tumor fraction.” It was Hamburger who presented the
results to the National Academy meeting, although he did
not appear as an author on the published paper (Cohen and
Levi-Montalcini 1956).
Rita recalled that Cohen had an interesting idea. If the
protein was present in the snake venom it might be present
also in the homologous salivary gland of mice. If so, one
Fig. 10 Influence of sarcoma fragments on embryonic sympathetic
ganglia of the chicken invitro. Left (3): control with fragments of
chicken heart (C). Right (4): small sarcoma fragments placed at a
distance of 1–2mm from the ganglia. Within 24h nerve fibres grew
radially in all directions forming a dense halo around the ganglion.
Reprinted by permission from the American Association for Cancer
Research: Levi-Montalcini R, Meyer H, Hamburger V, Invitro exper-
iments on the effects of mouse sarcomas 180 and 37 on the spinal and
sympathetic ganglia of the chick embryo. Cancer Res 1954, 14:49-57
Rendiconti Lincei. Scienze Fisiche e Naturali
1 3
would be able to extract a much larger amount of the growth-
promoting factor and in a much easier way. The experiment
was successful and showed that it is present in large amounts
in the submaxillary gland of adult male mice (Cohen 1960).
Therefore, the salivary glands of the mouse, especially the
male, provided a rich and easily available source of the pro-
tein, facilitating subsequent research. Thus, it was possible
to isolate a purified form of the protein and to obtain a spe-
cific antibody. In addition, Cohen (1960) showed that fol-
lowing a daily subcutaneous injection of the growth factor
there was a marked increase in protein, RNA and DNA con-
tent of the sympathetic chain ganglia, whereas the injection
of an antiserum to the same growth factor resulted in a total
destruction of them, not only in the mouse, but also in other
mammals. In the same issue of the journal Rita described the
impact of the antiserum at cellular level (Levi-Montalcini
and Booker 1960a, 1960b). As she commented later, the
entire chain of the paravertebral sympathetic ganglia was so
small as to appear as a thin string under a magnifying lens
and more than 95% of the neurons had disappeared. It was
on July 21, 1959, just before Cohen’s departure, when Rita
showed him the images under the microscope. In this last
collaborative work Rita and Cohen revealed the essential
role of NGF in the process of differentiation and in the sur-
vival of the neurons and this was another milestone in the
NGF history. As commented later by Cattaneo (2013), this
was the first phenotypic knockout obtained with antibodies.
On December 1958 Hamburger announced that budget
restrictions did not allow him to offer Cohen a position in
the Department. Therefore, Cohen moved to the Department
of Biochemistry of Vanderbilt University, Tennessee. This
marked the end of a short but most productive and happy
collaboration. Rita mentions a sentence pronounced by
Cohen: “Rita, you and I are good, but together we are won-
derful.” In March 1959 Hamburger announced that Rita had
been appointed Full Professor in his Department.
In the following years Cohen demonstrated that those
mice injected with the factor isolated from the mouse sali-
vary glands had a faster development of eye lid opening and
of tooth eruption. This observation was the beginning of a
new story developed by Cohen, a story that culminated with
the discovery of another growth factor, named epidermal
growth factor or EGF (Cohen 1962, 2008).
11 Back toItaly
In 1960, at the time when Cohen left St. Louis, the basic
investigations on NGF had been done with great success.
Rita realized it was necessary to concentrate her efforts
on identifying the structure of the new molecule and
the mechanisms of its action both during and after the
developmental stage. She was worried that she could not
continue the collaboration with Cohen and she felt that
collaboration with a biochemist would still be important.
She asked a young Italian physician, Pietro Angeletti, an
expert biochemist working at the Medical School of Wash-
ington University, if he had any possible interest in joining
her for the investigation on the NGF and he accepted.
Turin and Giuseppe Levi are now very distant in time,
but Rita never meant to stay out of Italy permanently. She
was very attached to her family and she was keen to share
her life with her sister Paola. In addition, she had in mind
to set up a new laboratory in Italy. Therefore, she decided
to ask Hamburger for a 3-month leave every year to spend
in her native country. Hamburger met her request with a
proper teaching schedule, while Pietro Angeletti was in
charge of and responsible for the research laboratory.
Satisfied with the agreement, in 1961 Rita went to
Washington to ask for financial support for her research
activity in Italy and she was successful. She decided not
to return to Turin, but she felt that Rome was a more
attractive city. In 1962 she had a lab at a Health Insti-
tute (Istituto Superiore di Sanità). In 1969 the centre was
upgraded to the Laboratory of Cell Biology of the Italian
National Research Council. The project was challenging.
For 30years, the investigations on the growth-promoting
molecule had been a kind of private hunting reserve of
Rita and the three main collaborators: Giuseppe Levi, Vik-
tor Hamburger and Stanley Cohen. Now NGF had an inter-
national passport and the number of publications abroad
was much more numerous than in Italy. Ralph Bradshaw,
for instance, became one of the most deeply involved sci-
entists in the United States addressing the issue of the
identification of the molecular composition of NGF (see
Shooter 2001). Ruth Hogue-Angeletti and Bradshaw of
Washington University identified the aminoacid sequence
of NGF, which was made up of two identical subunits con-
sisting of 118 aminoacids (Hogue-Angeletti and Bradshaw
1971; Hogue-Angeletti etal. 1973a, 1973b), and in 1983
the gene coding for NGF was also identified (Scott etal.
1983).
Rita started to travel back and forth between Rome and St.
Louis. On May 12, 1983, Nature (303:109–128) published
a supplement Science in Italy compiled by Robert Walgate,
Nature’s chief European correspondent, with the title Can
order spring from chaos? In her book (Levi-Montalcini
1988) Rita mentions this report to highlight the remarkable
differences in the work conditions between the United States
and Italy. However, she continued with a series of excellent
collaborators in addition to Pietro Angeletti: Pietro Calis-
sano, Luigi Aloe and later Antonino Cattaneo together with
a wide team of young investigators. A series of investiga-
tions was set up to establish several molecular mechanisms
of action of NGF (Angeletti etal. 1968; Levi-Montalcini
etal. 1974).
Rendiconti Lincei. Scienze Fisiche e Naturali
1 3
At a Confindustria conference held in Cernobbio in
2001, Rita launched the proposal to create a European Brain
Research Institute (EBRI). The Mayor of Turin, Sergio Chia-
mparino, offered full space in a new infrastructure with all
possible support to the initiative, as a kind of repatriation
of the lady who honoured Turin in the world. Meanwhile,
another offer came from Luigi Amadio, President of the
Santa Lucia Foundation, with one of the best Italian hospi-
tals specializing in nervous disorders and Rita chose to stay
in Rome. Thus, in 2004 Amadio created in a new premise
the European Centre for Brain Research (Centro europeo di
ricerche sul cervello, CERC). He moved his neuroscience
laboratories, previously hosted in the hospital, and made
an agreement to host two National Research Centres, one
of them being the one previously directed by Rita. Amadio
offered free space to host EBRI and an environment rich in
scientists and equipment. However, several problems soon
created conflicts that led Rita, as President of EBRI, to ask,
and to obtain on February 10, 2010, for a governmental
Commissioner to replace the Board of Directors and the Sci-
entific Council which contained three Nobel Laureates. The
news aroused amazement and criticism from the national
and international scientific community.
12 The Nobel Prize award
In 1986 Rita (Fig.11) and Cohen received the highest
scientific recognition for their outstanding achievements.
The Nobel Committee judged the topic of the two growth
factors, NGF and EGF, to be the target of the Prize. The
importance of the discovery is evident by the fact that it
signalled a new era in the study of the brain. NGF was the
first of a set of molecules able to modulate the functions
of the brain and its cells in health and disease. It took
30years before other molecules, which are now collec-
tively called neurotrophins, were discovered.
Among the experts there was a discussion as to why
Hamburger was not included in this prestigious award.
From what I reported in this long story it is clear that he
had a critical role in the different stages leading to the dis-
covery of the growth factors. In fact, Rita said in her Nobel
lecture (Levi-Montalcini 1986): “I dedicate this article to
Viktor Hamburger, who promoted and took part in this
search, and to whom I am forever indebted for invalu-
able suggestions and generosity. Without him, the Nerve
Growth Factor would never have come to our attention.”
Rita and Cohen met once more on April 22, 2009, on the
occasion of an international meeting held in Rome to cel-
ebrate Rita’s 100th birthday (Figs.12, 13, 14).
Fig. 11 Nobel Prize award, Stockholm 1986
Fig. 12 Birthday meeting in Rome, April 22, 2009. Rita and Stanley
Cohen. Courtesy of EBRI
Fig. 13 Birthday meeting in Rome, April 22, 2009. First row from
left: Aaron Ciechanover, Torsten Wiesel, Stanley Cohen and Giuliano
Amato. Above from left: Moses Chao, Ezio Giacobini, Elena Catta-
neo, Anders Björklund and James Fawcett. Courtesy of EBRI
Rendiconti Lincei. Scienze Fisiche e Naturali
1 3
13 Social andpolitical commitment
andnal years
In the 1970s Rita supported the campaign for a law in
favour of abortion to prevent women having to migrate
abroad for such a purpose. Both Rita and Levi were emi-
nent members of the Academy and Rita was very active
and influential to promote cultural activities. In addition,
she invested a significant fraction of the Nobel Prize in the
creation of the Fondazione Levi to be run by the Academy.
In 1992, with her sister Paola, she established the Rita
Levi-Montalcini Foundation in memory of their father
with the aim of helping young African women to gain a
leading role in the scientific and social life of their coun-
try through the awarding of scholarships (project called A
boarding school for Tuareg girls).
In 2001 Rita was appointed Senator for life and she was
regularly present at the Senate sessions. During the Prodi
government (2006–2008) she voted always in favour of
the Government and in some cases her vote was crucial
to avoid the Government’s fall. From 2006 to 2008 she
was Honorary President of the National Committee for
Bioethics. In 2010 the Minister of Education, University
and Research Mariastella Gelmini launched the Montalcini
Project for the return of young researchers to Italy.
On December 30, 2012, around lunchtime at her home in
Rome that she had shared with her sister Paola until the year
2000, she took a nap in an armchair and silently left us all.
She left a huge crowd of Italian and foreign admirers: pupils,
collaborators, outstanding personalities and ordinary people.
The coffin was exhibited in Rome and visited by academic
and political authorities. At her funeral in Turin on January
2, 2013, in addition to local authorities, about 5–7000 people
took part. Her ashes are now in the family tomb designed by
Gino, her architect brother.
Acknowledgements I would like to thank Prof. Germana Pareti and
Dr. Robin Harvey for illuminating discussions, and Maria Romanazzo
(Fregi e Majuscole, Turin) not only for copy-editing, but especially
for the organization of the whole architecture of text and illustrations.
A special mention to Piera Levi-Montalcini for precious information
and for help in collecting illustrations. This article is dedicated to my
father, Gerolamo Strata, MD, who was sentenced to prison in Savona
in the late 30s and then confined to Atripalda (Avellino) for criticism
of the fascist regime.
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