RESUMO
The development of physiological models that reproduce SARS-CoV-2 infection in primary human cells will be instrumental to identify host-pathogen interactions and potential therapeutics. Here, using cell suspensions directly from primary human lung tissues (HLT), we have developed a rapid platform for the identification of viral targets and the expression of viral entry factors, as well as for the screening of viral entry inhibitors and anti-inflammatory compounds. The direct use of HLT cells, without long-term cell culture and in vitro differentiation approaches, preserves main immune and structural cell populations, including the most susceptible cell targets for SARS-CoV-2; alveolar type II (AT-II) cells, while maintaining the expression of proteins involved in viral infection, such as ACE2, TMPRSS2, CD147 and AXL. Further, antiviral testing of 39 drug candidates reveals a highly reproducible method, suitable for different SARS-CoV-2 variants, and provides the identification of new compounds missed by conventional systems, such as VeroE6. Using this method, we also show that interferons do not modulate ACE2 expression, and that stimulation of local inflammatory responses can be modulated by different compounds with antiviral activity. Overall, we present a relevant and rapid method for the study of SARS-CoV-2.
Assuntos
Antivirais/uso terapêutico , Tratamento Farmacológico da COVID-19 , Pulmão/virologia , SARS-CoV-2/fisiologia , Internalização do Vírus , Adulto , Animais , Antivirais/farmacologia , COVID-19/imunologia , COVID-19/patologia , Células Cultivadas , Chlorocebus aethiops , Avaliação Pré-Clínica de Medicamentos , Drogas em Investigação/farmacologia , Drogas em Investigação/uso terapêutico , Células HEK293 , Interações Hospedeiro-Patógeno/efeitos dos fármacos , Humanos , Inflamação/patologia , Inflamação/terapia , Inflamação/virologia , Pulmão/patologia , SARS-CoV-2/efeitos dos fármacos , Células Vero , Internalização do Vírus/efeitos dos fármacosRESUMO
Effective function of CD8+ T cells and enhanced innate activation of DCs in response to HIV-1 is linked to protective antiviral immunity in controllers. Manipulation of DC targeting the master regulator TANK-binding Kinase 1 (TBK1) might be useful to acquire controller-like properties. Here, we evaluated the impact of the combination of 2´3´-c´diAM(PS)2 and Poly I:C as potential adjuvants capable of potentiating DC´s abilities to induce polyfunctional HIV-1 specific CD8+ T-cell responses in vitro and in vivo using a humanized BLT mouse model. Adjuvant combination enhanced TBK-1 phosphorylation and IL-12 and IFN-ß expression on DC and increased their ability to activate polyfunctional HIV-1-specific CD8+ T cells in vitro. Moreover, higher proportions of hBLT mice vaccinated with ADJ-DC exhibited less severe CD4+ T-cell depletion following HIV-1 infection compared to control groups. This was associated with infiltration of CD8+ T cells in the white pulp from the spleen, reduced spread of infected p24+ cells to LN, and with preserved abilities of CD8+ T cells from the spleen and blood of vaccinated animals to induce specific polyfunctional responses upon antigen stimulation. Therefore, priming of DC with PolyI:C and STING agonists might be useful for future HIV-1 vaccine studies.
Assuntos
Vacinas contra a AIDS , HIV-1 , Vacinas contra a AIDS/metabolismo , Adjuvantes Imunológicos/farmacologia , Animais , Linfócitos T CD4-Positivos , Linfócitos T CD8-Positivos , Células Dendríticas , Proteína do Núcleo p24 do HIV/metabolismo , Tecido Linfoide , Camundongos , Poli I-C/farmacologiaRESUMO
Zinc pyrithione (1a), together with its analogues 1b-h and ruthenium pyrithione complex 2a, were synthesised and evaluated for the stability in biologically relevant media and anti-SARS-CoV-2 activity. Zinc pyrithione revealed potent in vitro inhibition of cathepsin L (IC50=1.88 ± 0.49 µM) and PLPro (IC50=0.50 ± 0.07 µM), enzymes involved in SARS-CoV-2 entry and replication, respectively, as well as antiviral entry and replication properties in an ex vivo system derived from primary human lung tissue. Zinc complexes 1b-h expressed comparable in vitro inhibition. On the contrary, ruthenium complex 2a and the ligand pyrithione a itself expressed poor inhibition in mentioned assays, indicating the importance of the selection of metal core and structure of metal complex for antiviral activity. Safe, effective, and preferably oral at-home therapeutics for COVID-19 are needed and as such zinc pyrithione, which is also commercially available, could be considered as a potential therapeutic agent against SARS-CoV-2.
Assuntos
Tratamento Farmacológico da COVID-19 , Rutênio , Antivirais/farmacologia , Catepsina L , Humanos , Compostos Organometálicos , Piridinas , SARS-CoV-2RESUMO
Latency reversal agents (LRAs) have proven to induce HIV-1 transcription in vivo but are ineffective at decreasing the size of the latent reservoir in antiretroviral treated patients. The capacity of the LRAs to perturb the viral reservoir present in distinct subpopulations of cells is currently unknown. Here, using a new RNA FISH/flow ex vivo viral reactivation assay, we performed a comprehensive assessment of the viral reactivation capacity of different families of LRAs, and their combinations, in different CD4+ T cell subsets. We observed that a median of 16.28% of the whole HIV-reservoir induced HIV-1 transcripts after viral reactivation, but only 10.10% of these HIV-1 RNA+ cells produced the viral protein p24. Moreover, none of the LRAs were powerful enough to reactivate HIV-1 transcription in all CD4+ T cell subpopulations. For instance, the combination of Romidepsin and Ingenol was identified as the best combination of drugs at increasing the proportion of HIV-1 RNA+ cells, in most, but not all, CD4+ T cell subsets. Importantly, memory stem cells were identified as highly resistant to HIV-1 reactivation, and only the combination of Panobinostat and Bryostatin-1 significantly increased the number of cells transcribing HIV within this subset. Overall, our results validate the use of the RNA FISH/flow technique to assess the potency of LRAs among different CD4+ T cell subsets, manifest the intrinsic differences between cells that encompass the latent HIV reservoir, and highlight the difficulty to significantly impact the latent infection with the currently available drugs. Thus, our results have important implications for the rational design of therapies aimed at reversing HIV latency from diverse cellular reservoirs.
Assuntos
Fármacos Anti-HIV/farmacologia , Linfócitos T CD4-Positivos/imunologia , Infecções por HIV/imunologia , HIV-1/imunologia , Ativação Viral/imunologia , Latência Viral/imunologia , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/virologia , Depsipeptídeos/farmacologia , Diterpenos/farmacologia , Infecções por HIV/tratamento farmacológico , Infecções por HIV/virologia , HIV-1/efeitos dos fármacos , Humanos , Carga Viral , Ativação Viral/efeitos dos fármacos , Latência Viral/efeitos dos fármacosRESUMO
Since the start of the COVID-19 outbreak, pharmaceutical companies and research groups have focused on the development of vaccines and antiviral drugs against SARS-CoV-2. Here, we apply a drug repurposing strategy to identify drug candidates that are able to block the entrance of the virus into human cells. By combining virtual screening with in vitro pseudovirus assays and antiviral assays in Human Lung Tissue (HLT) cells, we identify entrectinib as a potential antiviral drug.
Assuntos
Benzamidas/farmacologia , Tratamento Farmacológico da COVID-19 , Indazóis/farmacologia , SARS-CoV-2/efeitos dos fármacos , Animais , Antivirais/farmacologia , Benzamidas/metabolismo , COVID-19/metabolismo , Linhagem Celular , Chlorocebus aethiops , Avaliação Pré-Clínica de Medicamentos , Reposicionamento de Medicamentos/métodos , Humanos , Indazóis/metabolismo , Pulmão/patologia , Pulmão/virologia , Simulação de Acoplamento Molecular , SARS-CoV-2/metabolismo , SARS-CoV-2/patogenicidade , Células Vero , Ligação Viral/efeitos dos fármacosRESUMO
The main obstacle to HIV eradication is the establishment of a long-term persistent HIV reservoir. Although several therapeutic approaches have been developed to reduce and eventually eliminate the HIV reservoir, only a few have achieved promising results. A better knowledge of the mechanisms involved in the establishment and maintenance of HIV reservoir is of utmost relevance for the design of new therapeutic strategies aimed at purging it with the ultimate goal of achieving HIV eradication or alternatively a functional cure. In this regard, it is also important to take a close look into the cellular HIV reservoirs other than resting memory CD4 T-cells with key roles in reservoir maintenance that have been recently described. Unraveling the special characteristics of these HIV cellular compartments could aid us in designing new therapeutic strategies to deplete the latent HIV reservoir.
Assuntos
Infecções por HIV/virologia , HIV-1/fisiologia , Latência Viral , Fármacos Anti-HIV/uso terapêutico , Terapia Antirretroviral de Alta Atividade , Contagem de Linfócito CD4 , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD4-Positivos/virologia , Infecções por HIV/tratamento farmacológico , Infecções por HIV/imunologia , Infecções por HIV/metabolismo , Histonas/metabolismo , Humanos , Metilação , Linfócitos T Citotóxicos/imunologia , Linfócitos T Citotóxicos/metabolismo , Carga Viral , Replicação ViralRESUMO
Resting CD4+ T-cells harboring inducible HIV proviruses are a critical reservoir in antiretroviral therapy (ART)-treated subjects. These cells express little to no viral protein, and thus neither die by viral cytopathic effects, nor are efficiently cleared by immune effectors. Elimination of this reservoir is theoretically possible by combining latency-reversing agents (LRAs) with immune effectors, such as CD8+ T-cells. However, the relative efficacy of different LRAs in sensitizing latently-infected cells for recognition by HIV-specific CD8+ T-cells has not been determined. To address this, we developed an assay that utilizes HIV-specific CD8+ T-cell clones as biosensors for HIV antigen expression. By testing multiple CD8+ T-cell clones against a primary cell model of HIV latency, we identified several single agents that primed latently-infected cells for CD8+ T-cell recognition, including IL-2, IL-15, two IL-15 superagonists (IL-15SA and ALT-803), prostratin, and the TLR-2 ligand Pam3CSK4. In contrast, we did not observe CD8+ T-cell recognition of target cells following treatment with histone deacetylase inhibitors or with hexamethylene bisacetamide (HMBA). In further experiments we demonstrate that a clinically achievable concentration of the IL-15 superagonist 'ALT-803', an agent presently in clinical trials for solid and hematological tumors, primes the natural ex vivo reservoir for CD8+ T-cell recognition. Thus, our results establish a novel experimental approach for comparative evaluation of LRAs, and highlight ALT-803 as an LRA with the potential to synergize with CD8+ T-cells in HIV eradication strategies.
Assuntos
Antivirais/farmacologia , Linfócitos T CD4-Positivos/virologia , Infecções por HIV/imunologia , Proteínas/farmacologia , Linfócitos T Citotóxicos/imunologia , Latência Viral/efeitos dos fármacos , Ensaio de Imunoadsorção Enzimática , ELISPOT , Citometria de Fluxo , Humanos , Reação em Cadeia da Polimerase , Proteínas Recombinantes de Fusão , Ativação Viral/efeitos dos fármacosRESUMO
BACKGROUND: In most patients, current antiretroviral therapy (ART) regimens can rapidly reduce plasma viral load. However, even after years of effective treatment, a significant proportion of patients show residual plasma viremia below the clinical detection limit. Although residual viremia might be associated with increased chronic immune activation and morbidity, its origin and its potential role in the replenishment of the viral reservoir during suppressive ART is not completely understood. We performed an in-depth genetic analysis of the total and episomal cell-associated viral DNA (vDNA) repertoire in purified CD4(+) T cell subsets of three HIV-infected individuals, and used phylogenetic analysis to explore its relationship with plasma viruses. RESULTS: The predominant proviral reservoir was established in naïve or memory (central and transitional) CD4(+) T cell subsets in patients harboring X4- or R5-tropic viruses, respectively. Regardless of the viral tropism, most plasma viruses detected under suppressive ART resembled the proviral reservoir identified in effector and transitional memory CD4(+) T-cell subsets in blood, suggesting that residual viremia originates from these cells in either blood or lymphoid tissue. Most importantly, sequences in episomal vDNA in CD4(+) T-cells were not well represented in residual viremia. CONCLUSIONS: Viral tropism determines the differential distribution of viral reservoir among CD4(+) T-cell subsets. In spite of viral tropism, the effector and transitional memory CD4(+) T-cells subsets are the main source of residual viremia during suppressive ART, even though their contribution to the total proviral pool is small. However, the lack of concordance between residual viremia and viral variants driving de novo infection of CD4(+) T cells on ART may reflect the predominance of defective plasma HIV RNA genomes. These findings highlight the need for monitoring the multiple viral RNA/DNA persistence markers, based on their differential contribution to viral persistence.
Assuntos
Fármacos Anti-HIV/uso terapêutico , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/virologia , Variação Genética , Infecções por HIV/virologia , HIV-1/genética , Viremia/virologia , Terapia Antirretroviral de Alta Atividade , DNA Viral/genética , Infecções por HIV/tratamento farmacológico , HIV-1/efeitos dos fármacos , HIV-1/fisiologia , Humanos , Masculino , Filogenia , Provírus/genética , RNA Viral/genética , Subpopulações de Linfócitos T/virologia , Carga Viral , Tropismo ViralRESUMO
UNLABELLED: Initiation of antiretroviral therapy during the earliest stages of HIV-1 infection may limit the seeding of a long-lasting viral reservoir, but long-term effects of early antiretroviral treatment initiation remain unknown. Here, we analyzed immunological and virological characteristics of nine patients who started antiretroviral therapy at primary HIV-1 infection and remained on suppressive treatment for >10 years; patients with similar treatment duration but initiation of suppressive therapy during chronic HIV-1 infection served as controls. We observed that independently of the timing of treatment initiation, HIV-1 DNA in CD4 T cells decayed primarily during the initial 3 to 4 years of treatment. However, in patients who started antiretroviral therapy in early infection, this decay occurred faster and was more pronounced, leading to substantially lower levels of cell-associated HIV-1 DNA after long-term treatment. Despite this smaller size, the viral CD4 T cell reservoir in persons with early treatment initiation consisted more dominantly of the long-lasting central-memory and T memory stem cells. HIV-1-specific T cell responses remained continuously detectable during antiretroviral therapy, independently of the timing of treatment initiation. Together, these data suggest that early HIV-1 treatment initiation, even when continued for >10 years, is unlikely to lead to viral eradication, but the presence of low viral reservoirs and durable HIV-1 T cell responses may make such patients good candidates for future interventional studies aiming at HIV-1 eradication and cure. IMPORTANCE: Antiretroviral therapy can effectively suppress HIV-1 replication to undetectable levels; however, HIV-1 can persist despite treatment, and viral replication rapidly rebounds when treatment is discontinued. This is mainly due to the presence of latently infected CD4 T cells, which are not susceptible to antiretroviral drugs. Starting treatment in the earliest stages of HIV-1 infection can limit the number of these latently infected cells, raising the possibility that these viral reservoirs are naturally eliminated if suppressive antiretroviral treatment is continued for extremely long periods of time. Here, we analyzed nine patients who started on antiretroviral therapy within the earliest weeks of the disease and continued treatment for more than 10 years. Our data show that early treatment accelerated the decay of infected CD4 T cells and led to very low residual levels of detectable HIV-1 after long-term therapy, levels that were otherwise detectable in patients who are able to maintain a spontaneous, drug-free control of HIV-1 replication. Thus, long-term antiretroviral treatment started during early infection cannot eliminate HIV-1, but the reduced reservoirs of HIV-1 infected cells in such patients may increase their chances to respond to clinical interventions aiming at inducing a drug-free remission of HIV-1 infection.
Assuntos
Antirretrovirais/administração & dosagem , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/virologia , Infecções por HIV/tratamento farmacológico , Infecções por HIV/virologia , HIV-1/isolamento & purificação , Adulto , Estudos de Coortes , DNA Viral/análise , DNA Viral/genética , Feminino , Infecções por HIV/imunologia , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Tempo , Resultado do TratamentoRESUMO
Combined treatment with interferon alpha (IFN-α) and ribavirin (RBV) can effectively cure HCV infection in a significant proportion of patients, but effects of this regimen on cellular reservoirs for human immunodeficiency virus type 1 (HIV-1) are unknown. Here, we show that treatment with IFN-α/RBV led to a moderate but significant and sustained decline of HIV-1 DNA in CD4 T cells from HIV-1/hepatitis C virus-coinfected patients receiving highly active antiretroviral therapy (n = 12). However, in vitro experiments failed to demonstrate an effect of pharmacological doses of IFN-α on HIV-1 reactivation. Together, these data suggest that treatment with IFN-α/RBV can moderately reduce the reservoir of HIV-1-infected CD4 T cells that persists despite suppressive antiretroviral therapy.
Assuntos
Linfócitos T CD4-Positivos/virologia , DNA Viral/sangue , Infecções por HIV/tratamento farmacológico , HIV-1/genética , Hepatite C/tratamento farmacológico , Ribavirina/uso terapêutico , Carga Viral/efeitos dos fármacos , Adulto , Idoso , Antivirais/uso terapêutico , Linfócitos T CD4-Positivos/imunologia , Coinfecção/sangue , Coinfecção/tratamento farmacológico , Coinfecção/imunologia , Coinfecção/virologia , Feminino , Infecções por HIV/imunologia , Infecções por HIV/virologia , HIV-1/isolamento & purificação , Hepatite C/imunologia , Hepatite C/virologia , Humanos , Interferon-alfa/uso terapêutico , Masculino , Pessoa de Meia-Idade , Estudos RetrospectivosRESUMO
During HIV-1 infection, dendritic cells (DC) facilitate dissemination of HIV-1 while trying to trigger adaptive antiviral immune responses. We examined whether increased HIV-1 capture in DC matured with LPS results in more efficient Ag presentation to HIV-1-specific CD4(+) and CD8(+) T cells. To block the DC-mediated trans-infection of HIV-1 and maximize Ag loading, we also evaluated a noninfectious integrase-deficient HIV-1 isolate, HIV(NL4-3ΔIN). We showed that higher viral capture of DC did not guarantee better Ag presentation or T cell activation. Greater HIV(NL4-3) uptake by fully LPS-matured DC resulted in higher viral transmission to target cells but poorer stimulation of HIV-1-specific CD4(+) and CD8(+) T cells. Conversely, maturation of DC with LPS during, but not before, viral loading enhanced both HLA-I and HLA-II HIV-1-derived Ag presentation. In contrast, DC maturation with the clinical-grade mixture consisting of IL-1ß, TNF-α, IL-6, and PGE(2) during viral uptake only stimulated HIV-1-specific CD8(+) T cells. Hence, DC maturation state, activation stimulus, and time lag between DC maturation and Ag loading impact HIV-1 capture and virus Ag presentation. Our results demonstrate a dissociation between the capacity to capture HIV-1 and to present viral Ags. Integrase-deficient HIV(NL4-3ΔIN) was also efficiently captured and presented by DC through the HLA-I and HLA-II pathways but in the absence of viral dissemination. HIV(NL4-3ΔIN) seems to be an attractive candidate to be explored. These results provide new insights into DC biology and have implications in the optimization of DC-based immunotherapy against HIV-1 infection.
Assuntos
Apresentação de Antígeno/imunologia , Células Dendríticas/imunologia , Células Dendríticas/virologia , HIV-1/imunologia , Ativação Linfocitária/imunologia , Linfócitos T/imunologia , Infecções por HIV/imunologia , Humanos , Microscopia Confocal , Microscopia Eletrônica de TransmissãoRESUMO
Men who have sex with men (MSM) with HIV are at high risk for squamous intraepithelial lesion (SIL) and anal cancer. Identifying local immunological mechanisms involved in the development of anal dysplasia could aid treatment and diagnostics. Here, we studied 111 anal biopsies obtained from 101 MSM with HIV, who participated in an anal screening program. We first assessed multiple immune subsets by flow cytometry, in addition to histological examination, in a discovery cohort. Selected molecules were further evaluated by immunohistochemistry in a validation cohort. Pathological samples were characterized by the presence of resident memory T cells with low expression of CD103 and by changes in natural killer cell subsets, affecting residency and activation. Furthermore, potentially immunosuppressive subsets, including CD15+CD16+ mature neutrophils, gradually increased as the anal lesion progressed. Immunohistochemistry verified the association between the presence of CD15 in the epithelium and SIL diagnosis for the correlation with high-grade SIL. A complex immunological environment with imbalanced proportions of resident effectors and immune-suppressive subsets characterized pathological samples. Neutrophil infiltration, determined by CD15 staining, may represent a valuable pathological marker associated with the grade of dysplasia.
Assuntos
Neoplasias do Ânus , Infecções por HIV , Antígenos CD15 , Humanos , Masculino , Infecções por HIV/imunologia , Infecções por HIV/complicações , Infecções por HIV/patologia , Neoplasias do Ânus/patologia , Neoplasias do Ânus/imunologia , Adulto , Pessoa de Meia-Idade , Antígenos CD15/metabolismo , Homossexualidade Masculina , Lesões Intraepiteliais Escamosas/patologia , Canal Anal/patologia , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/metabolismo , Antígenos CD/metabolismo , Neutrófilos/imunologia , Neutrófilos/patologia , Neutrófilos/metabolismo , Biópsia , Imuno-Histoquímica , Cadeias alfa de Integrinas/metabolismoRESUMO
BACKGROUND: Toll-like receptors (TLRs) are crucial for recognition of pathogen-associated molecular patterns by cells of the innate immune system. TLRs are present and functional in CD4⺠T cells. Memory CD4⺠T cells, predominantly central memory cells (TCM), constitute the main reservoir of latent HIV-1. However, how TLR ligands affect the quiescence of latent HIV within central memory CD4⺠T cells has not been studied. RESULTS: We evaluated the ability of a broad panel of TLR agonists to reactivate latent HIV-1. The TLR-1/2 agonist Pam3CSK4 leads to viral reactivation of quiescent HIV in a model of latency based on cultured TCM and in resting CD4⺠T cells isolated from aviremic patients. In addition, we investigated the signaling pathway associated with Pam3CSK4 involved in HIV-1 reactivation. We show that the transcription factors NFκB, NFAT and AP-1 cooperate to induce viral reactivation downstream of TLR-1/2 stimulation. Furthermore, increasing levels of cyclin T1 is not required for TLR-mediated viral reactivation, but induction of viral expression requires activated pTEFb. Finally, Pam3CSK4 reactivates latent HIV-1 in the absence of T cell activation or proliferation, in contrast to antigen stimulation. CONCLUSIONS: Our findings suggest that the signaling through TLR-1/2 pathway via Pam3CSK4 or other reagents should be explored as an anti-latency strategy either alone or in combination with other anti-latency drugs.
Assuntos
Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/virologia , HIV-1/fisiologia , Lipopeptídeos/metabolismo , Receptor 1 Toll-Like/agonistas , Receptor 2 Toll-Like/agonistas , Ativação Viral , Adolescente , Adulto , Humanos , Lipopeptídeos/imunologia , Transdução de Sinais , Receptor 1 Toll-Like/imunologia , Receptor 2 Toll-Like/imunologia , Adulto JovemRESUMO
BACKGROUND: Immune hyperactivation in immunodiscordant patients can induce residual HIV replication and limit CD4 T cell recovery. We assessed the impact of raltegravir intensification on CD4 T cell recovery and viral persistence. METHODS: We performed a randomized, controlled, pilot trial. Patients with CD4 T cell counts <350 cells/mm(3) despite suppressive antiretroviral therapy were randomized (2 : 1) to intensify with raltegravir (intensified arm, n = 30) or to continue with the same regimen (control arm, n = 14) for 48 weeks. Then, the control individuals intensified their treatment for 24 weeks (delayed-intensification arm). We analysed changes in CD4 T cell counts, total and episomal HIV DNA in peripheral blood mononuclear cells and predictive factors for response. RESULTS: Raltegravir intensification induced a rapid increase in CD4 T cell counts (week 12) (P = 0.007), although this was not sustained over time. Control patients maintained constant but slow increases in CD4 T cell counts (present in the pre-study period), reaching CD4 T cell counts similar to those of patients in the intensification arm at week 48. This effect was confirmed by the analysis of the delayed-intensification arm. Proviral DNA levels remained stable in both arms over time; episomal DNA forms and ultrasensitive plasma viral load were barely detected during the study. Increases in CD4 T cell counts were associated with low baseline CD95 expression in CD4 and CD8 T cells (P = 0.020). CONCLUSIONS: Raltegravir intensification modestly impacts viral dynamics and induces a rapid but limited gain in CD4 T cell counts in immunodiscordant patients. Residual viral replication does not seem to be the main cause of unsatisfactory CD4 T cell recovery in these patients.
Assuntos
Antirretrovirais/administração & dosagem , Terapia Antirretroviral de Alta Atividade/métodos , Linfócitos T CD4-Positivos/imunologia , Infecções por HIV/tratamento farmacológico , Infecções por HIV/imunologia , Pirrolidinonas/administração & dosagem , Adulto , Sangue/virologia , Contagem de Linfócito CD4 , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Raltegravir Potássico , Carga ViralRESUMO
In order to design strategies for eradication of HIV-1 from infected individuals, detailed insight into the HIV-1 reservoirs that persist in patients on suppressive antiretroviral therapy (ART) is required. In this regard, most studies have focused on integrated (proviral) HIV-1 DNA forms in cells circulating in blood. However, the majority of proviral DNA is replication-defective and archival, and as such, has limited ability to reveal the dynamics of the viral population that persists in patients on suppressive ART. In contrast, extrachromosomal (episomal) viral DNA is labile and as a consequence is a better surrogate for recent infection events and is able to inform on the extent to which residual replication contributes to viral reservoir maintenance. To gain insight into the diversity and compartmentalization of HIV-1 under suppressive ART, we extensively analyzed longitudinal peripheral blood mononuclear cells (PBMC) samples by deep sequencing of episomal and integrated HIV-1 DNA from patients undergoing raltegravir intensification. Reverse-transcriptase genes selectively amplified from episomal and proviral HIV-1 DNA were analyzed by deep sequencing 0, 2, 4, 12, 24 and 48 weeks after raltegravir intensification. We used maximum likelihood phylogenies and statistical tests (AMOVA and Slatkin-Maddison (SM)) in order to determine molecular compartmentalization. We observed low molecular variance (mean variability ≤0.042). Although phylogenies showed that both DNA forms were intermingled within the phylogenetic tree, we found a statistically significant compartmentalization between episomal and proviral DNA samples (P<10(-6) AMOVA test; Pâ=â0.001 SM test), suggesting that they belong to different viral populations. In addition, longitudinal analysis of episomal and proviral DNA by phylogeny and AMOVA showed signs of non-chronological temporal compartmentalization (all comparisons P<10(-6)) suggesting that episomal and proviral DNA forms originated from different anatomical compartments. Collectively, this suggests the presence of a chronic viral reservoir in which there is stochastic release of infectious virus and in which there are limited rounds of de novo infection. This could be explained by the existence of different reservoirs with unique pharmacological accessibility properties, which will require strategies that improve drug penetration/retention within these reservoirs in order to minimise maintenance of the viral reservoir by de novo infection.
Assuntos
Fármacos Anti-HIV/farmacologia , Terapia Antirretroviral de Alta Atividade , Infecções por HIV/tratamento farmacológico , HIV-1/efeitos dos fármacos , Pirrolidinonas/farmacologia , DNA Circular/análise , DNA Circular/efeitos dos fármacos , DNA Circular/genética , DNA Viral/análise , DNA Viral/efeitos dos fármacos , Reservatórios de Doenças , Infecções por HIV/sangue , Infecções por HIV/virologia , HIV-1/genética , Interações Hospedeiro-Patógeno , Humanos , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/virologia , Filogenia , Plasmídeos/efeitos dos fármacos , Plasmídeos/genética , Raltegravir Potássico , Análise de Sequência de DNA , Carga ViralRESUMO
Resident memory T cells (TRM) present at the respiratory tract may be essential to enhance early SARS-CoV-2 viral clearance, thus limiting viral infection and disease. While long-term antigen-specific TRM are detectable beyond 11 months in the lung of convalescent COVID-19 patients, it is unknown if mRNA vaccination encoding for the SARS-CoV-2 S-protein can induce this frontline protection. Here we show that the frequency of CD4+ T cells secreting IFNγ in response to S-peptides is variable but overall similar in the lung of mRNA-vaccinated patients compared to convalescent-infected patients. However, in vaccinated patients, lung responses present less frequently a TRM phenotype compared to convalescent infected individuals and polyfunctional CD107a+ IFNγ+ TRM are virtually absent in vaccinated patients. These data indicate that mRNA vaccination induces specific T cell responses to SARS-CoV-2 in the lung parenchyma, although to a limited extend. It remains to be determined whether these vaccine-induced responses contribute to overall COVID-19 control.
Assuntos
COVID-19 , SARS-CoV-2 , Humanos , Células T de Memória , Memória Imunológica , Pulmão , Vacinação , Anticorpos AntiviraisRESUMO
Human immunodeficiency virus (HIV) infection induces immunological dysfunction, which limits the elimination of HIV-infected cells during treated infection. Identifying and targeting dysfunctional immune cells might help accelerate the purging of the persistent viral reservoir. Here, we show that chronic HIV infection increases natural killer (NK) cell populations expressing the negative immune regulator KLRG1, both in peripheral blood and lymph nodes. Antiretroviral treatment (ART) does not reestablish these functionally impaired NK populations, and the expression of KLRG1 correlates with active HIV transcription. Targeting KLRG1 with specific antibodies significantly restores the capacity of NK cells to kill HIV-infected cells, reactivates latent HIV present in CD4+ T cells co-expressing KLRG1, and reduces the intact HIV genomes in samples from ART-treated individuals. Our data support the potential use of immunotherapy against the KLRG1 receptor to impact the viral reservoir during HIV persistence.
Assuntos
Infecções por HIV , HIV-1 , Receptores Imunológicos , Humanos , Infecções por HIV/tratamento farmacológico , Infecções por HIV/genética , Células Matadoras Naturais , Lectinas Tipo C/genética , Receptores Imunológicos/genética , Latência ViralRESUMO
Latency is a major barrier towards virus elimination in HIV-1-infected individuals. Yet, the mechanisms that contribute to the maintenance of HIV-1 latency are incompletely understood. Here we describe the Schlafen 12 protein (SLFN12) as an HIV-1 restriction factor that establishes a post-transcriptional block in HIV-1-infected cells and thereby inhibits HIV-1 replication and virus reactivation from latently infected cells. The inhibitory activity is dependent on the HIV-1 codon usage and on the SLFN12 RNase active sites. Within HIV-1-infected individuals, SLFN12 expression in PBMCs correlated with HIV-1 plasma viral loads and proviral loads suggesting a link with the general activation of the immune system. Using an RNA FISH-Flow HIV-1 reactivation assay, we demonstrate that SLFN12 expression is enriched in infected cells positive for HIV-1 transcripts but negative for HIV-1 proteins. Thus, codon-usage dependent translation inhibition of HIV-1 proteins participates in HIV-1 latency and can restrict the amount of virus release after latency reversal.
Assuntos
Linfócitos T CD4-Positivos , HIV-1 , Uso do Códon , HIV-1/fisiologia , RNA Viral/genética , Latência Viral/genéticaRESUMO
Antiretroviral drug susceptibility tests facilitate therapeutic management of HIV-1-infected patients. Although genotyping systems are affordable, inaccuracy in the interpretation of complex mutational patterns may limit their usefulness. Currently available HIV-1 phenotypic assays are based on the generation of recombinant viruses in which the specific viral gene of interest, derived from a patient plasma sample, is cloned into a susceptible genetic viral backbone prior to in vitro drug susceptibility evaluation. Nevertheless, in the case of protease inhibitors, not only are mutations in the HIV-1 protease-coding region involved in resistance, but the role of Gag in drug susceptibility has also recently been reported. In order to avoid the inherent limitations resulting from partial cloning of the viral genome, we designed and evaluated a new experimental strategy to test the in vitro susceptibility of primary viral isolates to protease inhibitors. Our protocol, which is based on a two-round infection protocol using the reporter TZM-bl cell line, showed a good correlation with genotypic resistance prediction and with the Antivirogram phenotypic assay, in both protease-recombinant viruses and primary viral isolates. The protocol is suitable for any HIV-1 subtype and enables rapid in-house measurement of protease inhibitor susceptibility, thus making it possible to evaluate the concomitant effects of both patient-derived gag and protease-coding regions.
Assuntos
Inibidores da Protease de HIV/farmacologia , HIV-1/efeitos dos fármacos , Infecções por HIV/virologia , HIV-1/genética , HIV-1/isolamento & purificação , Humanos , Testes de Sensibilidade Microbiana/métodos , Recombinação GenéticaRESUMO
Elite controllers spontaneously maintain undetectable levels of HIV-1 replication for reasons that remain unclear. Here, we show that in elite controllers, direct ex vivo infection of purified CD4 T cells without prior in vitro activation results in disproportionately low levels of integrated HIV-1 DNA relative to the quantity of reverse transcripts, while the levels of two-long terminal repeat (2-LTR) circles were excessively elevated relative to those of integrated HIV-1 DNA. This indicates that chromosomal HIV-1 integration is inhibited in ex vivo-infected CD4 T cells from elite controllers. This defect in HIV-1 integration was unrelated to p21, a host protein that can restrict early HIV-1 replication steps, and was not visible following infection of in vitro-activated CD4 T cells from elite controllers. These data contribute to increasing evidence that intrinsic inhibition of specific HIV-1 replication steps plays an important role in the ability of elite controllers to maintain undetectable viral loads.