C Hammer

Publications (34)12.5 Total impact

• Article: Exceptionally long survival time in xenogeneic organ transplantation.

  C Hammer, C Chaussy, H Welter, J Wembacher, G Höbel, W Brendel
  Transplantation Proceedings 04/1981; 13(1 Pt 2):881-4. · 1.00 Impact Factor
• Article: [Assessment of lymphatic cells in natural and artificial allografts (author's transl)].

  J Wembacher, I Senftleber, J Gokel, C Hammer, W Brendel
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  ABSTRACT: Transfer of "passenger lymphocytes" within a transplant initiates allogeneic rejection. As compared with peripheral lymphocytes, which show no different in vitro reaction, infiltrating cells from natural and artificial grafts are good stimulator, bad responder but powerful suppressor cells. These T-suppressor cells, which arose during rejection are enriched in the graft. The assumption is that the function of this relatively small number of lymphocytes is to suppress the local immunological rejection mechanisms. They cannot inhibit the proliferation of peripheral cytotoxic cells.
  Chirurgisches Forum für experimentelle und klinische Forschung 02/1980;
• Article: Mitigation of hyperacute rejection by antilymphocyte globulin (ALG).

  C Hammer, G Krebs, C Chaussy, K Pfeifer, K Schmidt, W Land, W Brendel
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  ABSTRACT: In HR, primarily humoral immunologic factors trigger a sequence of events that finally destroys the transplanted organ. Unspecific trapping of WBC diminishes the RBF, especially in the first compartment--the cortex. Pretreatment with ALG is able to suppress this cellular participation partially, thus postponing the stop of RBF without preventing the influence of humoral factors on the graft. As shown by pathologic and functional criteria recorded for 8 hr, an exclusive measurement of total RBF does not reflect an inhibition of the course of HR.
  Transplantation Proceedings 04/1979; 11(1):31-5. · 1.00 Impact Factor
• Article: [Prolonged survival time of xenogeneic kidney transplants following intravenous application of concanavalin A].

  H Welter, H Krause, C Hammer, W Brendel
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  ABSTRACT: Concanavalin A is used as a mitogen for the stimulation of lymphocytes in vitro. It increases the proliferation of different populations of lymphocytes and activates the function of regulator lymphocytes. This effect appears to be modified in vivo in such a way that daily IV application prolongs survival times of allogeneic and xenogeneic kidney grafts significantly. The reason seems to be an influence on behavior, which is reflected in a pronounced peripheral lymphopenia. To support and investigate this mechanism, further combinations of antilymphocyte globulin, fox red blood cells, and Concanavalin A pretreatment were used in pilot studies.
  Chirurgisches Forum für experimentelle und klinische Forschung 02/1979;
• Article: [Clinical significance of immunological findings for the survival time of kidney transplants with antilymphocyte globulin therapy].

  W Bullinger, C Hammer, W Land, H Welter
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  ABSTRACT: A balanced combination of immunosuppressive regimens like cortisone, azathioprine and ALG can not only reduce the frequency, but also the severity of rejection episodes in kidney transplant patients. Addition of ALG influences the lymphocyte populations, especially T-lymphocytes. The significant reduction produced obviously includes cytotoxic effector lymphocytes as well as socalled regulator cells (suppressor cells). It seems as if this beneficial function for the graft is not only reduced under immunosuppressive therapy and administration of ALG, but disappears during rejection crises. The results indicate, however, that these cell populations recover quickly after finishing the immunosuppressive regimen.
  Chirurgisches Forum für experimentelle und klinische Forschung 02/1979;
• Article: Prolonged survival time of canine xenografts using a new schedule of horse--anti-dog lymphocytic globulin (ALG) therapy.

  W Brendel, K H Duswald, J von Scheel, C Chaussy, H W Sollinger, C Hammer
  Transplantation Proceedings 04/1977; 9(1):379-81. · 1.00 Impact Factor
• Article: Langzeitüberleben von Hauttransplantaten im xenogenen System Wolf-Hund

  K. H. Duswald, J. v. Scheel, C. Hammer, W. Brendel
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  ABSTRACT: Das zoologisch als xenogen bezeichnete System Wolf-Hund ist nach immunologischen Kriterien nher verwandt als DL-A-kompatible und MLC-negative unverwandte Hunde. Unbehandelte Hauttransplantate wurden nach 12,5 Tagen (Allotransplantate verwandter Hunde nach 9,1 Tagen) abgestoen. Immunsuppression mit ALG verlngert diese berlebenszeit erheblich auf 85,6, im Einzelfall ber 200 Tage. Es liegt hier eine Spender-Empfnger-Kombination vor, deren schwache Histoinkompatibilitt durch MLC und DL-A nicht zum Ausdruck kommt. Vermutlich ist sie durch andere genetische Systeme bedingt, die heute noch nicht zu bestimmen sind. Es konnte jedenfalls gezeigt werden, da Transplantationen zwischen unterschiedlichen Spezies sogar mit besserem Erfolg als bei nicht verwandten Allotransplantaten mglich sind. Ziel der weiteren Forschung mu es sein, ein solches System auch fr die menschliche Transplantation zu finden. Damit wren klinische Xenotransplantationen in grerem Ausma als bisher mglich.In contrast to the zoological definition that wolf and dog belong to different species, it is shown by this study that in terms of immunology both species appear to be even closer related than DL-A compatible and MLC negative unrelated dogs. However, this close relationship is not expressed in DL-A or MLC tissue typing. Wolf skin-graft survival time in untreated dogs was 12,5, in AlG-treated dogs 85,6 days. The survival time in this system may be less dependent on DL-A or MLC histocompatibility than on other genetic systems, which are hitherto not sufficiently defined. An accidental, speciesspecific accordance in these systems may explain the obviously weak histocompatibility barrier between wolf and dog. It is concluded that in certain species-combinations xenotransplantation could be more successful than random allotransplantation. The availability of a xenogeneic species related to man similar as wolf to dog would markedly facilitate clinical xenotransplantation.
  Research in Experimental Medicine 09/1976; 167(3):255-266.
• Article: [Long-term graft survival in the xenogeneic system wolf-dog (author's transl)].

  K H Duswald, J v Scheel, C Hammer, W Brendel
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  ABSTRACT: In contrast to the zoological definition that wolf and dog belong to different species, it is shown by this study that in terms of immunology both species appear to be even closer related than DL-A compatible and MLC negative unrelated dogs. However, this close relationship is not expressed in DL-A or MLC tissue typing. Wolf skin-graft survival time in untreated dogs was 12,5, in ALG-treated dogs 85,6 days. The survival time in this system may be less dpendent on DL-A or MLC histocompatibility than on other genetic systems, which are hitherto not sufficiently defined. An accidental, speciesspecific accordance in these systems may explain the obviously weak histocompatbility barrier between wolf and dog. It is concluded that in certain species-combinations xenotransplantation could be more successful than random allotransplantation. The availability of a xenogeneic species related to man similar as wolf to dog would markedly facilitate clinical xenotransplantation.
  Research in Experimental Medicine 08/1976; 167(3):255-66.
• Article: Survival times of skin and kidney grafts within different canine species in relation to their genetic markers.

  C Hammer, C Chaussy, J von Scheel, H Pongratz, E Roscher, W Brendel
  Transplantation Proceedings 10/1975; 7(3):439-47. · 1.00 Impact Factor
• Article: Xenogeneic skin and kidney transplants in a closely related canine system, fox-dog.

  C Chaussy, C Hammer, J von Scheel, K Pielsticker, H W Sollinger, K J Pfeifer, H Pongratz, W Brender
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  ABSTRACT: Fox kidney and skin grafts were transplanted into dog recipients. Fox kidneys, transplanted en bloc into untreated dogs, survived 6.2 +/- 0.4 days. The skin transplants survived 5.9 +/- 1.4 days. The grafted kidneys showed almost normal function before rejection. Both skin and kidney rejection were mediated through a cellular mechansim. Performed natural antibodies against donor tissue were not present in the serum of the recipients. These results combined with absorption studies suggested a close relationship between fox and dog, but different number and morphology of chromosomes, immunoelectrophoretic patterns of serum proteins, and disparities of the transplantation antigens proved that the fox is a species quite separate from the dog. It was concluded that the fox-dog system, with its similarity to the chimpanzeeman relationship, offers a unique model to study clinically applicable methods of managing xenografts between closely related species.
  Transplantation 09/1975; 20(2):150-4. · 4.00 Impact Factor
• Article: [Blood flow measurements with 133xenon during prolonged hyperacute xenogenic rejection].

  K R Schmidt, K J Pfeifer, C Chaussy, C Hammer, G Krebs, H G Heinze
  Strahlentherapie. Sonderbände 02/1975; 74:211-9.
• Article: [Post mortem magnification angiography of the kidneys, using fat soluble contrast media (author's transl)].

  K J Pfeifer, U Klein, C Chaussy, C Hammer, K Pielsticker, H Haendle, J Lissner
  Fortschritte auf dem Gebiete der Röntgenstrahlen und der Nuklearmedizin 11/1974; 121(4):472-6.
• Article: [Experimental xenografting in widely divergent species. Modification of the hyperacute xenogeneic rejection of kidneys from pigs (donor) by extreme hemodilution of dogs (recipients) (author's transl)].

  L Fiedler, C Hammer, K Messmer, W Land, K Holper, W Klövekorn, K Pielsticker, C Chaussy, W Brendel
  Research in Experimental Medicine 07/1974; 163(2):137-53.
• Article: [Proceedings: Ultrastructural changes in the glomerulus following xenogenic kidney hemotransfusion: in vitro studies on hyperacute transplantation rejection].

  G Hübner, C Chaussy, C Hammer, K Pielsticker
  Verhandlungen der Deutschen Gesellschaft für Pathologie 02/1974; 58:584.
• Article: Experimentelle Xenotransplantation in entfernt stammesverwandten Speciessystemen

  L. Fiedler, C. Hammer, K. Messmer, W. Land, K. Holper, W. Klövekorn, K. Pielsticker, C. Chaussy, W. Brendel
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  ABSTRACT: E vivo-Hmoperfusion von Schweinenieren durch unbehandelte Hunde fhrt schon nach 15 min zu einem vlligen Funktionsausfall der Organe auf Grund der hyperakuten xenogenen Abstoungsreaktion. Eine Vorperfusion der Nieren mit einer 4C-Nierenperfusionslsung verzgert das Sistieren des renalen Blutflusses um fast 2 Std.Prformierte natrliche Antikrper zusammen mit Komplement, Thrombocyten, Leukocyten sowie von vasoaktiven Substanzen werden als auslsende Momente bei dieser Transplantatabstoung diskutiert.Extreme isovolmische Hmodilution des Empfngers mit 6% Dextran 60 bis zu einem Hmatokrit von 7,5% eliminiert den grten Teil der prformierten natrlichen Antikrper. Gleichzeitig werden alle anderen Blutbestandteile wie Komplement und Zellen deutlich vermindert.Die Reduzierung dieser Faktoren durch graduellen Ersatz des Gesamtblutes mit Dextran 60 und gewaschenen autologen Erythrocyten fhrt zu einer signifikanten Abschwchung der xenogenen Abstoungsreaktion und damit zu einer Verbesserung der Funktion, die sich in einer Verlngerung der Nierendurchblutungszeit und einem starken Anstieg der Urinproduktion uert. E vivo hemoperfusion of pig kidneys by untreated dogs results in a complete deterioration of function within 15 min caused by a hyperacute xenogeneic rejection. Flush out of these kidneys by a special perfusion solution of 4C is already able to delay the complete stop of the renal blood flow to approximately 2 hrs.Preformed natural antibodies together with complement, platelets, white blood cells and vasoactive substances are discussed to be the reason for this type of graft rejection.Extreme isovolemic hemodilution of the recipient dog with 6% Dextran 60 to a hematocrit of 7.5% eliminates most of the preformed natural antibodies. In parallel, all other factors like complement, globulins, thrombocytes and leucocytes are significantly decreased.The wash out of these factors by gradually replacing whole blood with only Dextran 60 and washed autologous erythrocytes leads to a striking mitigation of the xenogeneic reaction, resulting in a prolongation of the functional survival as indicated by extending the renal blood flow up to 11 hrs and a tremendous increase of urine production.
  Research in Experimental Medicine 01/1974; 163(2):137-153.
• Article: Experimental xenogeneic kidney transplantation in closely related species

  C. Chaussy, C. Hammer, J. v. Scheel, F. Eisenberger, K. Pielsticker, W. Brendel
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  ABSTRACT: To study the survival time of kidney-transplants in closely related species cat kidneys were transplanted to the iliac vessels of mongrel dogs by an en bloc method. A type of delayed hyperacute rejection was observed. The function time of the transplant kidneys ranged from 15 to 24 hrs. The decrease of complement activity and the appearance of cat-tissue protein in serum and urine samples show that the rejection began at an early stage. Since the antigen-antibody reaction seems to be finished after 6 hrs, indicated by an increase of complementactivity, the final loss of function may be effected by an unspecific reaction. Recipients survived after removal of the transplant and got a second kidney graft 3 weeks after the first set. These kidneys were rejected within 15–20 min with the sign of typical hyperacute rejection.Um das Verhalten vascularisierter Xenotransplantate zwischen Tieren enger zoologischer Verwandtschaft zu untersuchen, wurden Katzennieren en bloc auf Hunde transplantiert. In diesem System zeigte sich, mit einer Funktionsdauer von 15–24 Std, der Typ einer verzgert hyperakuten Abstoung. Der Abfall des Komplements im peripheren Blut und das Auftreten von Katzenprotein im Urin schon whrend der ersten Stunden deutet auf einen frheren Beginn dieser Reaktion hin, whrend die endgltige Zerstrung des Transplantates durch unspezifische, jedoch von der Antigen-Antikrper-Reaktion gestartete Mechanismen bedingt zu sein scheint. Den Empfngern dieser Ersttransplantate wurden 3 Wochen spter mit einer Ex vivo-Hmoperfusion eine zweite Katzenniere angeschlossen. Innerhalb von 15–20 min waren diese Nieren unter dem Bild einer typischen hyperakuten Abstoung zerstrt.
  Research in Experimental Medicine 11/1973; 159(4):266-275.
• Article: [Animal experimental investigations of in situ perfusion and cooling of the kidney (author's transl)].

  F Eisenberger, C Chaussy, U Klein, K J Pfeifer, K Pielsticker, R Rothe, C Hammer, H G Heinze
  Der Urologe 10/1973; 12(5):268-73. · 0.50 Impact Factor
• Article: Experimental xenogeneic kidney transplantation in closely related systems. E vivo hemoperfusion of kidney in the system cat (donor) to dog (recipient).

  C Hammer, C Chaussy, G Krebs, J von Scheel, W Brendel
  Research in Experimental Medicine 04/1973; 160(1):32-44.
• Article: Experimental xenogeneic kidney transplantation in closely related systems

  C. Hammer, C. Chaussy, G. Krebs, J. v. Scheel, W. Brendel
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  ABSTRACT: E-vivo hemoperfusions of cat kidneys by untreated dogs were performed. Because analyses of blood and urine can be done at any time, this model has the methodical advantage above transplantation. The function time of the xenogeneic cat kidneys ranged from 10–15 hrs. In contrast to xenotransplants of closely related animals within a zoological family, which are destroyed by cellular actions, the rejection of grafts of nearly related species within a zoological order seems to be governed by humoral mechanisms. Speciesspecific but not organspecific PNAB trigger humoral and cellular factors, that lead to progressiv organ destruction. Urine and serum parameters show, that the HXR in nearly related species, compared to HXR in widely divergent species, is delayed and weakened and should therefore be distinguished.E vivo-Hmoperfusion von Katzennieren durch unbehandelte Hunde wurde ausgefhrt. Dieses Modell erlaubt Blut- und Urinanalysen zu jeder gewnschten Zeit und besitzt so einen gewissen methodischen Vorteil gegenber der Transplantation. Die xenogenen Nieren wurden bis zu 15 Std funktionstchtig erhalten. Im Gegensatz zu xenogenen Transplantationen bei Tieren innerhalb einer zoologischen Familie, bei denen cellulre Abstoungsreaktionen auftreten, scheint in diesem System von Tieren, die einer gemeinsamen Ordnung angehren, der humorale Typ der Abstoungsreaktion vorzuherrschen. Speciesspezifische, jedoch nicht organspezifische prformierte natrliche Antikrper setzen eine Folge von humoralen und cellulren Mechanismen in Gang, die zu einer fortschreitenden Zerstrung des Organs fhren. Im Urin und Serum gemessene Parameter zeigen, da eine hyperakute xenogene Abstoungsreaktion, die im nah verwandten Speciessystem auftritt, verglichen mit der HXAR bei entfernt verwandten Species abgeschwcht und verzgert ist und daher unterschieden werden sollte.
  Research in Experimental Medicine 02/1973; 160(1):32-44.
• Article: [Experimental xenografting in closely related species (cat-dog) (author's transl)].

  C Chaussy, C Hammer, F Eisenberger, K Pielsticker, W Brendel
  Urologia Internationalis 02/1973; 28(3):230-5. · 0.99 Impact Factor