Guido Poli

San Raffaele Scientific Institute | OSR · Division of Immunology, Transplantation and Infectious Diseases DITID

SARS-CoV-2 is a novel coronavirus that emerged in China at the end of 2019 causing the severe disease known as coronavirus disease 2019 (COVID-19). SARS-CoV-2, as to the previously highly pathogenic human coronaviruses named SARS-CoV, the etiological agent of severe acute respiratory syndrome (SARS), has a zoonotic origin, although SARS-CoV-2 preci...

Upon infection, severe acute respiratory syndrome—coronavirus 2 (SARS-CoV-2) is predicted to interact with diverse cellular functions, such as the nonsense-mediated decay (NMD) pathway, as suggested by the identification of the core NMD factor upframeshift-1 (UPF1) in the SARS-CoV-2 interactome, and the retrograde transport from the Golgi to the en...

ZIKV is a neurotropic virus that invades neural progenitor cells (NPCs), causing inhibition of their proliferation and maturation into neurons and glial cells. We have shown previously that heparin, an anticoagulant also used widely during pregnancy, prevents ZIKV-induced cell death with negligible inhibition of virus replication.

In addition to CD4+ T lymphocytes, myeloid cells and, particularly, differentiated macrophages are targets of human immunodeficiency virus type-1 (HIV-1) infection via the interaction of gp120Env with CD4 and CCR5 or CXCR4. Both T cells and macrophages support virus replication, although with substantial differences. In contrast to activated CD4+ T...

Efficient, wide-scale testing for SARS-CoV-2 is crucial for monitoring the incidence of the infection in the community. The gold standard for COVID-19 diagnosis is the molecular analysis of epithelial secretions from the upper respiratory system captured by nasopharyngeal (NP) or oropharyngeal swabs. Given the ease of collection, saliva has been pr...

In addition to CD4+ T cells, tissue-resident macrophages are target of productive HIV-1 infection. Unlike CD4+ T lymphocytes they are characterized by a substantial resistance to the cytopathic effects triggered by viral infection. This feature, in addition to their homeostatic self-renewal capacity, strongly support the hypothesis that macrophages...

The introduction of combination antiretroviral therapy (cART) has switched HIV-1 infection from a lethal disease to a chronic one. Indeed, cART is a lifelong treatment since its interruption is always followed by a rapid rebound of viremia from both cellular and anatomical viral reservoirs where the integrated HIV-1 provirus remains transcriptional...

As already discussed for T cell lines, also myeloid cell lines as served as the earliest models of chronic HIV infection. They were particularly relevant in the late 1980s and early 1990s when most experimental in vitro infections were based on laboratory-adapted “T-cell tropic” strains of HIV-1, such as LAI/IIIB or others, that later were found to...

This book details the development of methods and models to study the HIV-1 viral reservoir with the ultimate goal of achieving a functional cure of HIV infection. Chapters are divided into six parts covering cell lines, in vitro and ex vivo primary cell models of persistent infection, in vitro and ex vivo tissue-derived models, infected animal mode...

In the summer of 1981, a new deadly disease suddenly emerged targeting young men having sexwith men (MSM); three years later, a new virus, an exogenous human retrovirus, later named humanimmunodeficiency virus (HIV), was demonstrated to be the causative agent of the new disease, theAcquired Immuno-Deficiency Syndrome (AIDS), affecting, in addition...

In addition to CD4+ T lymphocytes, myeloid cells, and, particularly, differentiated macrophages, are targets of the human immunodeficiency virus type-1 (HIV-1) infection via interaction of gp120Env with CD4 and CCR5 or CXCR4. Both T cells and macrophages support virus replication although with substantial differences. In contrast to activated CD4+...

Efficient wide-scale testing for SARS-CoV-2 is crucial for monitoring the incidence of the infection in the community. The gold standard for COVID-19 diagnosis is the molecular analysis of epithelial secretions from the upper respiratory system captured by nasopharyngeal (NP) swabs, which requires the intervention of trained personnel. Given the ea...

Viral invasion of target cells triggers an immediate intracellular host defense system aimed at preventing further propagation of the virus. Viral genomes or early products of viral replication are sensed by a number of pattern recognition receptors, leading to the synthesis and production of type I interferons (IFNs) that, in turn, activate a casc...

Background: Biobanks are imperative infrastructures, particularly during outbreaks, when there is an obligation to acquire and share knowledge as quick as possible to allow for implementation of science-based preventive, diagnostic, prognostic and therapeutic strategies. Methods: We established a COVID-19 biobank with the aim of collecting high-...

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), the etiological agent of coronavirus disease 2019 (COVID-19), is transmitted person-to-person via respiratory droplets and, likely, via smaller droplet nuclei light enough to remain suspended in the air for hours and contaminate surfaces particularly in indoor conditions. Thus, effective...

Effective and economical measures are needed to either prevent or inhibit the replication of SARS-CoV-2, the causative agent of COVID-19, in the upper respiratory tract. As fumigation of vinegar at low concentration (0.34%) ameliorated the symptoms of mild SARS-CoV-2 infection, we tested in vitro the potential antiviral activity of vinegar and of i...

HIV-1 infects CD4+ T lymphocytes with a 'helper' function and myeloid cells, mostly tissue-resident macrophages. While infection of CD4 T lymphocytes in the absence of combination antiretroviral therapy (cART) leads to their depletion and to a profound immunodeficiency, macrophages are resistant to virus-induced cytopathicity and are a source of in...

The human immunodeficiency virus type-1 (HIV-1) establishes a state of latent infection in a small number of CD4+ T lymphocytes that, nonetheless, represent a major obstacle to viral eradication. We here show that Tripartite Motif-containing protein 22 (TRIM22), an epigenetic inhibitor of Specificity protein 1 (Sp1)-dependent HIV-1 transcription, i...

We have reported that short-term stimulation of primary human monocyte-derived macrophages (MDM) with interferon-γ (IFN-γ) and tumor necrosis factor-α (TNF-α), i.e. M1 polarization, leads to a significant containment of virus replication. Here we show that M1-MDM restimulation with these cytokines 7 days after infection (M12 MDM) promoted an increa...

Over 4 days, more than 500 scientists involved in HIV persistence research shared their new unpublished data and designed future perspectives towards ART-free HIV remission. This 8th International Workshop on HIV Persistence followed the format of past conferences but further focused on encouraging participation of young investigators, especially t...

Over 4 days, more than 500 scientists involved in HIV persistence research shared their new unpublished data and designed future perspectives towards ART-free HIV remission. This 8th International Workshop on HIV Persistence followed the format of past conferences but further focused on encouraging participation of young investigators, especially t...

Infection of target cells by the human immunodeficiency virus type-1 (HIV-1) is hampered by constitutively expressed host cell proteins preventing or curtailing virus replication and therefore defined as “restriction factors”. Among them, members of the tripartite motif (TRIM) family have emerged as important players endowed with both antiviral eff...

HIV-1 insertions targeting BACH2 or MLK2 are enriched and persist for decades in hemato-poietic cells from patients under combination antiretroviral therapy. However, it is unclear how these insertions provide such selective advantage to infected cell clones. Here, we show that in 30/87 (34%) patients under combination antiretroviral therapy, BACH2...

Among interferon (IFN) inducible antiviral factors both tripartite motif-containing protein 22 (TRIM22) and class II transactivator (CIITA) share the capacity of repressing human immunodeficiency virus type 1 (HIV-1) proviral transcription. TRIM22 is constitutively expressed in a subset of U937 cell clones poorly permissive to HIV-1 replication, wh...

Several studies demonstrated a relevant role of polymorphisms located within the HLA-B and -C loci and the Killer Immunoglobulin Receptors (KIRs) 3DL1 and 3DS1 in controlling HIV-1 replication. KIRs are regulatory receptors expressed at the surface of NK and CD8+ T-cells that specifically bind HLA-A and -B alleles belonging to the Bw4 supratype and...

Zika virus (ZIKV) is a recently re-emerged flavivirus transmitted to humans by mosquito bites but also from mother to fetus and by sexual intercourse. We here show that primary human endometrial stromal cells (HESC) are highly permissive to ZIKV infection and support its in vitro replication. ZIKV envelope expression was detected in the endoplasmic...

We investigated the potential anti-HIV-1 activity of the candidate microbicide 5-hydroxytyrosol (5-HT) both in primary human cervical tissue explants (CTE), established from tissues of women undergoing histerectomy, and in endometrium-associated leukocytes (EAL). CTE were exposed to either the laboratory-adapted HIV-1BaL or to primary viral isolate...

Background: We have previously reported that short-term exposure of primary MDM to pro-inflammatory cytokines (IFN-γ plus TNF-α), ie, “M1 polarization”, partially prevented productive virus infection and reduced proviral transcription. Materials and Methods: M1-polarized MDM were restimulated with M1 cytokines 7 days after R5 HIV-1 infection (M1×2...

Zika virus (ZIKV) is a recently re-emerged flavivirus transmitted to humans by mosquito bites but also from mother to fetus and by sexual intercourse. We here show for the first time that primary human endometrial stromal cells (HESC) are highly permissive to ZIKV infection and support its in vitro replication. ZIKV envelope expression was detected...

M1/M2 cytokine-dependent polarization of primary human MDMs has been shown to contain CCR5-dependent (R5) HIV-1 replication. In this study, a similar effect was achieved when monocytes were first polarized toward M1 or M2 and were infected 7 d after their differentiation into MDMs, regardless of whether the cytokines were removed 18 h after cell st...

Background We previously demonstrated that the HLA class II transactivator CIITA inhibits HIV-1 replication in T cells by competing with the viral transactivator Tat for the binding to Cyclin T1 subunit of the P-TEFb complex. Here, we analyzed the anti-viral function of CIITA in myeloid cells, another relevant HIV-1 target cell type. We sinvestigat...

In addition to CD4 T lymphocytes, HIV-1 infects tissue macrophages that can actively accumulate infectious virions in vacuolar subcellular structures mostly connected to the plasma membrane and recently termed virus-containing compartments (VCCs). The VCC-associated HIV-1 reservoir of infected macrophages can be either increased or depleted by immu...

While the existence of latently infected CD4+ T cells has been demonstrated in infected individuals receiving cART, whether primary myeloid cells are latently infected remains to be firmly established. In this regard, we have previously reported that short-term exposure of primary MDM established from seronegative individuals to pro-inflammatory cy...

Over 4 days, more than 270 scientists involved in HIV persistence research convened to share their data and discuss future avenues to control HIV without continuous antiretroviral therapy. This 7th International Workshop on HIV Persistence followed the format of the preceding conferences but more time was given for discussing abstracts submitted by...

Significance A proportion of the variation in HIV-1 viral load in the infected population is influenced by host genetics. Using a large sample of infected individuals ( n = 6,315) with genome-wide genotype data, we sought to map genomic regions that influence HIV viral load and quantify their impact. We identified amino acid positions located in th...

Background: Intestinal macrophages are key regulators of inflammatory responses to the gut microbiome and play a central role in maintaining tissue homeostasis and epithelial integrity. However, little is known about the role of these cells in HIV infection, a disease fuelled by intestinal inflammation, a loss of epithelial barrier function and in...

Significance A major obstacle to the eradication of HIV-1 by combination antiretroviral therapy (cART) is the formation of cellular reservoirs in CD4 ⁺ T lymphocytes (carrying latently integrated provirus) and tissue macrophages. Infected macrophages assemble new virions in subcellular vacuoles known as virus-containing compartments (VCC), hiding t...

Understanding the mechanisms by which some individuals are able to naturally control HIV-1 infection is an important goal of AIDS research. We here describe the case of an HIV-1+ woman, CASE1, who has spontaneously controlled her viremia for the last 14 of her 20 years of infection. CASE1 has been clinically monitored since 1993. Detailed immunolog...

Macrophages are a relevant target of HIV-1 infection and a peculiar viral reservoir in individuals receiving cART because of their capacity to actively generate and store new progeny virions in intracellular vacuolar compartments of debated origin. Therefore, we investigated the functional nature of this intracellular compartment in terms of its re...

An intrinsic property of all retroviruses is their capacity to establish a state of latent infection in addition to active viral replication. Both genetic and epigenetic factors contribute to silence the integrated provirus and are nowadays targets of experimental approaches aiming at reactivating virus expression in order to kill the infected cell...

Human Retroviruses: Methods and Protocols collects key experimental protocols that have provided the basis of the major discoveries of the field. Split into five sections, this detailed volume covers mapping of the HIV life cycle, isolation, co-receptor use, and cell tropism of HIV-1, in vivo quantification of HIV-1, biological aspects of HIV-1, as...

Tripartite motif-containing 22 (TRIM22) is an interferon-induced protein that inhibits HIV-1 transcription and replication in vitro. Two single nucleotide missense polymorphisms rs7935564A/G (SNP-1) and rs1063303C/G (SNP-2) characterize the coding sequence of human TRIM22 gene. We tested whether these variants affected the inhibitory effect of TRIM...

Cell-associated receptor for urokinase plasminogen activator (uPAR) is released as both full-length soluble uPAR (suPAR) and cleaved (c-suPAR) form that maintain ability to bind to integrins and other receptors, thus triggering and modulating cell signaling responses. Concerning HIV-1 infection, plasma levels of suPAR have been correlated with the...

Absolute levels of HIV replication, number of dead cells, uPA, PAI-I, suPAR and MCP-1 in culture supernatants. Levels of reverse transcriptase activity (indicative of productive virus replication), number of death cells (estimated by the levels of LDH), and of CCL2/MCP-1, uPA, PAI-1 and suPAR were measured in culture supernatants collected every 3...

In vitro HIV infection and modulation of the number of HIV+ and uPA+ cells. IHC analysis for HIV p24Gag and uPA antigens was used for estimating the number of cells expressing virus and uPA at day 0, 6 and 12 post infection. (A) HIV p24+ cells were detected starting from 6 days of histoculture. No difference between viral strains was observed. (B)...

Tonsils of HAART-treated HIV+ individual released both full-length and cleaved suPAR. UPAR forms and HIV p24Gag were evaluated in the conditioned supernatant after 3 days of histoculture of tonsils from MA35. In parallel, conditioned supernatants from in vitro HIV infected tonsils were also measured. (TIF)

Includes Note S1: the cohorts and individuals contributing to the International Consortium for the Genomics of HIV, Tables S1, S2, S3, Figures S1, S2, S3, S4, S5 and supplementary references. (DOC)

Multiple genome-wide association studies (GWAS) have been performed in HIV-1 infected individuals, identifying common genetic influences on viral control and disease course. Similarly, common genetic correlates of acquisition of HIV-1 after exposure have been interrogated using GWAS, although in generally small samples. Under the auspices of the In...

Background: Human immunodeficiency virus type 1 (HIV-1) infection is associated with a massive depletion of intestinal CD4(+) T cells that is only partially reversed by combination antiretroviral therapy (cART). Here, we assessed the ability of nucleoside reverse-transcriptase inhibitor/nonnucleoside reverse-transcriptase inhibitor treatment to re...

Mononuclear phagocytes play a fundamental role in the tissue homeostasis and innate defenses against viruses and other microbial pathogens. In addition, they are likely involved in several steps of cancer development. Circulating monocytes and tissue macrophages are target cells of viral infections, including human cytomegalovirus, human herpes vir...

Objective: Functional polarization of human monocyte-derived macrophages (MDMs) into M1 cells leads to inhibition of R5 HIV-1 replication and viral DNA synthesis in comparison to control, unpolarized cells together with CD4 downregulation from the cell surface and upregulation of CCR5-binding chemokine secretion. We here investigated whether a pos...