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1.
J Infect Dis ; 2024 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-38478746

RESUMEN

In the recent mpox outbreak, people living with HIV (PLWH) were at high risk both for contracting infection and for suffering a more severe disease course. We studied cellular and humoral immune responses elicited by mpox infection (n = 5; n = 3 PLWH) or smallpox vaccination (n = 17; all PLWH) in a cohort of men who have sex with men. All PLWH were successfully treated, with stable CD4 counts and undetectable HIV viral loads. 11/17 vaccinated individuals had received childhood smallpox vaccination. In this group of individuals, both two-dose MVA-vaccination and natural infection evoked mpox-specific immune responses mediated by B cells as well as CD4 and CD8 T cells. This study improves our understanding of smallpox vaccination mediated cross-reactivity to other orthopox viruses, and the long-lasting durability of childhood smallpox vaccination mediated immune responses including in PLWH.

2.
Infection ; 52(3): 1087-1097, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38326527

RESUMEN

BACKGROUND: Innate lymphoid cells (ILCs) are key organizers of tissue immune responses and regulate tissue development, repair, and pathology. Persistent clinical sequelae beyond 12 weeks following acute COVID-19 disease, named post-COVID syndrome (PCS), are increasingly recognized in convalescent individuals. ILCs have been associated with the severity of COVID-19 symptoms but their role in the development of PCS remains poorly defined. METHODS AND RESULTS: Here, we used multiparametric immune phenotyping, finding expanded circulating ILC precursors (ILCPs) and concurrent decreased group 2 innate lymphoid cells (ILC2s) in PCS patients compared to well-matched convalescent control groups at > 3 months after infection or healthy controls. Patients with PCS showed elevated expression of chemokines and cytokines associated with trafficking of immune cells (CCL19/MIP-3b, FLT3-ligand), endothelial inflammation and repair (CXCL1, EGF, RANTES, IL-1RA, PDGF-AA). CONCLUSION: These results define immunological parameters associated with PCS and might help find biomarkers and disease-relevant therapeutic strategies.


Asunto(s)
COVID-19 , Convalecencia , Citocinas , Linfocitos , Síndrome Post Agudo de COVID-19 , Humanos , COVID-19/inmunología , COVID-19/diagnóstico , Masculino , Femenino , Persona de Mediana Edad , Adulto , Linfocitos/inmunología , Citocinas/inmunología , SARS-CoV-2/inmunología , Inmunidad Innata , Anciano , Quimiocinas/inmunología
3.
Infection ; 51(4): 1141-1145, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-36641506

RESUMEN

PURPOSE: To analyze sensitivity and specificity of the rapid point-of-care (POC) eazyplex testing platform for bacterial sexually transmitted infections (STI) among men who have sex with men (MSM). METHODS: 272 anal, urethral, and pharyngeal swabs collected from 153 MSM were tested by both the eazyplex platform and an in-house PCR or culture in the university microbiology reference laboratory. RESULTS: Compared to the reference diagnostic method, the overall sensitivity/specificity of eazyplex was 88%/98% for N. gonorrhoeae, 82%/100% for C. trachomatis, 70%/ > 99% for U. urealyticum, and 85%/98% for M. hominis, respectively. Sensitivity for N. gonorrhoeae and U. urealyticum in urethral samples was 100%. CONCLUSION: With good to very good sensitivity depending on the sampling site and pathogen as well as very good specificity overall the eazyplex platform is a useful rapid diagnostic method for POC bacterial STI-testing especially for N. gonorrhoeae and C. trachomatis, allowing for almost immediate treatment initiation.


Asunto(s)
Infecciones por Chlamydia , Gonorrea , Minorías Sexuales y de Género , Masculino , Humanos , Homosexualidad Masculina , Infecciones por Chlamydia/diagnóstico , Neisseria gonorrhoeae/genética , Chlamydia trachomatis/genética , Pruebas en el Punto de Atención , Gonorrea/diagnóstico , Gonorrea/microbiología
4.
Infection ; 51(6): 1823-1829, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37526898

RESUMEN

BACKGROUND: Currently available antiretroviral 2-drug regimen (2DR) fixed dose combinations may not be suitable for specific situations including the presence of resistance associated mutations (RAM) or drug - drug interactions (DDI). The data on the use of the non-nucleoside reverse transcriptase inhibitor doravirine (DOR) and the integrase inhibitor dolutegravir (DTG) as an alternative 2DR remain scarce. METHODS: People living with HIV with DOR + DTG as a 2DR are being followed in a prospective observational study. RESULTS: This analysis describes 85 participants with a median age of 57 years. Median CD4-nadir was 173/µl and a majority (66%) had a history of HIV-associated or AIDS-defining conditions. Antiretroviral history was mostly extensive, and documentation of RAM was frequent. The main reasons for choosing DOR + DTG were DDI (29%), tolerability (25%), and cardiovascular risk reduction (21%). Plasma viral load at switch was < 50 copies/ml in all but 3 instances, median CD4 count was 600/µl. DOR + DTG was later changed to another regimen in 10 participants after a median of 265 days, the other 75 participants have remained on DOR + DTG for a median of 947 days. CONCLUSION: DOR + DTG as a 2DR proved to be a durable treatment option even in extensively pretreated individuals.


Asunto(s)
Síndrome de Inmunodeficiencia Adquirida , Fármacos Anti-VIH , Infecciones por VIH , Humanos , Persona de Mediana Edad , Infecciones por VIH/tratamiento farmacológico , Resultado del Tratamiento , Antirretrovirales/uso terapéutico , Oxazinas/uso terapéutico , Síndrome de Inmunodeficiencia Adquirida/tratamiento farmacológico , Fármacos Anti-VIH/uso terapéutico , Carga Viral
5.
J Infect Dis ; 224(11): 1925-1934, 2021 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-33963757

RESUMEN

BACKGROUND: Early HIV diagnosis allows combination antiretroviral therapy (cART) initiation in the first days of life following in utero (IU) infection. The impact of early cART initiation on infant viral reservoir size in the setting of high-frequency cART nonadherence is unknown. METHODS: Peripheral blood total HIV DNA from 164 early treated (day 0-21 of life) IU HIV-infected South African infants was measured using droplet digital PCR at birth and following suppressive cART. We evaluated the impact of cART initiation timing on HIV reservoir size and decay, and on the risk of subsequent plasma viremia in cART-suppressed infants. RESULTS: Baseline HIV DNA (median 2.8 log10 copies/million peripheral blood mononuclear cells, range 0.7-4.8) did not correlate with age at cART initiation (0-21 days) but instead with maternal antenatal cART use. In 98 infants with plasma viral suppression on cART, HIV DNA half-life was 28 days. However, the probability of maintenance of plasma aviremia was low (0.46 at 12 months) and not influenced by HIV DNA load. Unexpectedly, longer time to viral suppression was associated with protection against subsequent viral rebound. CONCLUSIONS: With effective prophylaxis against mother-to-child transmission, cART initiation timing in the first 3 weeks of life is not critical to reservoir size.


Asunto(s)
Terapia Antirretroviral Altamente Activa/métodos , Infecciones por VIH/tratamiento farmacológico , VIH-1 , Transmisión Vertical de Enfermedad Infecciosa , Carga Viral/efectos de los fármacos , Adulto , Femenino , VIH-1/efectos de los fármacos , VIH-1/genética , Humanos , Recién Nacido , Transmisión Vertical de Enfermedad Infecciosa/prevención & control , Leucocitos Mononucleares/virología , Reacción en Cadena de la Polimerasa , Embarazo , Sudáfrica
6.
Infection ; 48(5): 681-686, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32394344

RESUMEN

INTRODUCTION: Data on people living with human immunodeficiency virus (PLWH) in the current SARS-CoV-2 pandemic are still scarce. This case series of 33 PLWH patients with COVID-19 reveals symptoms and outcome in this special population. METHODS: Retrospective analysis of anonymized data including age, gender, HIV-associated parameters, symptoms, and outcome. RESULTS: Three out of 32 patients with documented outcomes died (9%). 91% of the patients recovered and 76% have been classified as mild cases. All patients were on antiretroviral treatment, of them 22 on tenofovir-containing regimen and 4 on the protease inhibitor darunavir. CONCLUSIONS: This preliminary case series does not support excess morbidity and mortality among symptomatic COVID-19 PLWH and with viral suppression on ART. SARS-CoV-2 infections may occur during boosted darunavir-based and/or on tenofovir-containing ART.


Asunto(s)
Betacoronavirus/patogenicidad , Infecciones por Coronavirus/virología , Darunavir/uso terapéutico , Infecciones por VIH/virología , VIH/patogenicidad , Neumonía Viral/virología , Tenofovir/uso terapéutico , Adulto , Terapia Antirretroviral Altamente Activa , Betacoronavirus/efectos de los fármacos , Betacoronavirus/inmunología , COVID-19 , Coinfección , Infecciones por Coronavirus/tratamiento farmacológico , Infecciones por Coronavirus/mortalidad , Infecciones por Coronavirus/patología , Femenino , VIH/efectos de los fármacos , VIH/inmunología , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/mortalidad , Infecciones por VIH/patología , Humanos , Masculino , Persona de Mediana Edad , Pandemias , Neumonía Viral/tratamiento farmacológico , Neumonía Viral/mortalidad , Neumonía Viral/patología , Estudios Retrospectivos , SARS-CoV-2 , Índice de Severidad de la Enfermedad , Análisis de Supervivencia , Carga Viral/efectos de los fármacos
7.
J Infect Dis ; 219(9): 1407-1417, 2019 04 16.
Artículo en Inglés | MEDLINE | ID: mdl-30624717

RESUMEN

BACKGROUND: Susceptibility to coinfections in human immunodeficiency virus (HIV)-infected patients remains increased despite antiretroviral therapy (ART). To elucidate mechanisms involved in immune reconstitution, we studied immune activation, immune exhaustion, and HIV- and copathogen-specific T-cell responses in children before and after ART. METHODS: We prospectively enrolled 25 HIV-infected children to study HIV-, cytomegalovirus (CMV)-, and tuberculosis (TB)-specific T-cell responses before and 1 year after initiation of ART using intracellular cytokine (interleukin-2, interferon-γ, tumor necrosis factor-α) staining assays after in vitro stimulation. We further measured expression of activation, immune exhaustion, and memory phenotype markers and studied proliferative responses after antigen stimulation. RESULTS: We observed differential, pathogen-specific changes after 1 year of ART in cytokine profiles of CD4 T-cell responses that were associated with shifts in memory phenotype and decreased programmed cell death 1 (PD-1) expression. The proliferative capacity of HIV- and PPD-specific responses increased after 1 year of ART. Of note, the recovery of CMV- and TB-specific responses was correlated with a decrease in PD-1 expression (r = 0.83, P = .008 and r = 0.81, P = .0007, respectively). CONCLUSIONS: Reconstitution of immune responses on ART is associated with alterations in T-cell phenotype, function, and PD-1 expression that are distinct for HIV, TB, and CMV. The PD-1 pathway represents a potential target for immunotherapy in HIV-infected patients on ART with insufficient immune reconstitution.


Asunto(s)
Linfocitos T CD4-Positivos/inmunología , Citomegalovirus/inmunología , Infecciones por VIH/tratamiento farmacológico , VIH/inmunología , Reconstitución Inmune , Mycobacterium tuberculosis/inmunología , Antirretrovirales/uso terapéutico , Linfocitos T CD4-Positivos/metabolismo , Linfocitos T CD8-positivos/fisiología , Proliferación Celular , Niño , Preescolar , Citocinas/metabolismo , Femenino , Humanos , Memoria Inmunológica , Activación de Linfocitos , Masculino , Fenotipo , Receptor de Muerte Celular Programada 1/metabolismo , Estudios Prospectivos
8.
Infection ; 47(1): 95-102, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30269210

RESUMEN

PURPOSE: To determine whether changing from a tenofovir disoproxil fumarate (TDF)- to a tenofovir alafenamide fumarate (TAF)-containing regimen is correlated with weight changes in a human immunodeficiency virus (HIV)-positive adult cohort. METHODS: Retrospective analysis was conducted of data gathered from routine care in a university hospital in Munich, Germany, between July 2015 and June 2017. Data from patients' charts were extracted and a two-step approach was applied. First, weight/BMI progression within 1 year after initiation of either TDF or TAF was compared. Subsequently, weight measurements within subjects changing from a TDF- to a TAF-containing antiretroviral regimen were analyzed by means of a repeated measurements general linear model. RESULTS: After 360 days of initiating TAF, patients showed a mean (± standard deviation) percentual weight increase of 3.17 ± 0.21, whereas after 360 days of initiating TDF, patients only showed a mean (± standard deviation) percentual weight increase of 0.55 ± 0.17. The repeated measurements general linear model for within-subjects design showed a statistically significant correlation in weight after changing from a TDF to a TAF containing antiretroviral regimen. The weight difference between the two measurements while on TDF was not statistically significant, but every measure after switching to TAF was significantly higher than the previous. CONCLUSION: Changing from a TDF- to a TAF-containing regimen is correlated with weight gain in this retrospectively analyzed real-world cohort in Munich, Germany.


Asunto(s)
Adenina/análogos & derivados , Fármacos Anti-VIH/uso terapéutico , Seropositividad para VIH/tratamiento farmacológico , Tenofovir/uso terapéutico , Aumento de Peso/efectos de los fármacos , Pérdida de Peso/efectos de los fármacos , Adenina/administración & dosificación , Adenina/uso terapéutico , Adulto , Alanina , Fármacos Anti-VIH/administración & dosificación , Estudios de Cohortes , Femenino , Fumaratos/administración & dosificación , Fumaratos/uso terapéutico , Alemania , Hospitales Universitarios , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Tenofovir/administración & dosificación
10.
J Virol ; 88(13): 7678-82, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24741087

RESUMEN

Myeloid-derived suppressor cells (MDSC) are immature myeloid cells with immunosuppressive function. Compared to the level in healthy controls (HC), no elevation of MDSC in chronic hepatitis C (cHEP-C) patients was found, and there was no difference in MDSC based on genotype or viral load (P > 0.25). Moreover, MDSC of cHEP-C patients inhibited CD8 T cell function as efficiently as MDSC of HC did. Since we detected neither quantitative nor qualitative differences in MDSC of cHEP-C patients relative to those of HC, we postulate that MDSC in peripheral blood are most likely not significant regarding immune dysfunction in cHEP-C.


Asunto(s)
Linfocitos T CD8-positivos/inmunología , Hepacivirus/inmunología , Hepatitis C Crónica/inmunología , Activación de Linfocitos/inmunología , Células Mieloides/inmunología , Carga Viral/inmunología , Presentación de Antígeno , Linfocitos T CD8-positivos/metabolismo , Estudios de Casos y Controles , Femenino , Citometría de Flujo , Hepacivirus/genética , Hepacivirus/aislamiento & purificación , Hepatitis C Crónica/sangre , Hepatitis C Crónica/virología , Humanos , Inmunofenotipificación , Masculino , Células Mieloides/metabolismo
11.
Immunology ; 143(2): 193-201, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24724694

RESUMEN

Methods for identifying physiologically relevant CD8 T-cell epitopes are critically important not only for the development of T-cell-based vaccines but also for understanding host-pathogen interactions. As experimentally mapping an optimal CD8 T-cell epitope is a tedious procedure, many bioinformatic tools have been developed that predict which peptides bind to a given MHC molecule. We assessed the ability of the CD8 T-cell epitope prediction tools syfpeithi, ctlpred and iedb to foretell nine experimentally mapped optimal HIV-specific epitopes. Randomly - for any of the subjects' HLA type and with any matching score - the optimal epitope was predicted in seven of nine epitopes using syfpeithi, in three of nine epitopes using ctlpred and in all nine of nine epitopes using iedb. The optimal epitope within the three highest ranks was given in four of nine epitopes applying syfpeithi, in two of nine epitopes applying ctlpred and in seven of nine epitopes applying iedb when screening for all of the subjects' HLA types. Knowing the HLA restriction of the peptide of interest improved the ranking of the optimal epitope within the predicted results. Epitopes restricted by common HLA alleles were more likely to be predicted than those restricted by uncommon HLA alleles. Epitopes with aberrant lengths compared with the usual HLA-class I nonamers were most likely not predicted. Application of epitope prediction tools together with literature searches for already described optimal epitopes narrows down the possibilities of optimal epitopes within a screening peptide of interest. However, in our opinion, the actual fine-mapping of a CD8 T-cell epitope cannot yet be replaced.


Asunto(s)
Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD4-Positivos/virología , Simulación por Computador , Mapeo Epitopo/métodos , Epítopos de Linfocito T , VIH-1/inmunología , VIH-1/patogenicidad , Antígenos de Histocompatibilidad Clase I/inmunología , Epítopos Inmunodominantes , Vacunas contra el SIDA/inmunología , Línea Celular , Biología Computacional , Humanos , Reproducibilidad de los Resultados , Programas Informáticos
12.
Nat Med ; 2024 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-38843818

RESUMEN

After sporadic reports of post-treatment control of HIV in children who initiated combination anti-retroviral therapy (cART) early, we prospectively studied 284 very-early-cART-treated children from KwaZulu-Natal, South Africa, after vertical HIV transmission to assess control of viremia. Eighty-four percent of the children achieved aviremia on cART, but aviremia persisting to 36 or more months was observed in only 32%. We observed that male infants have lower baseline plasma viral loads (P = 0.01). Unexpectedly, a subset (n = 5) of males maintained aviremia despite unscheduled complete discontinuation of cART lasting 3-10 months (n = 4) or intermittent cART adherence during 17-month loss to follow-up (n = 1). We further observed, in vertically transmitted viruses, a negative correlation between type I interferon (IFN-I) resistance and viral replication capacity (VRC) (P < 0.0001) that was markedly stronger for males than for females (r = -0.51 versus r = -0.07 for IFN-α). Although viruses transmitted to male fetuses were more IFN-I sensitive and of higher VRC than those transmitted to females in the full cohort (P < 0.0001 and P = 0.0003, respectively), the viruses transmitted to the five males maintaining cART-free aviremia had significantly lower replication capacity (P < 0.0001). These data suggest that viremic control can occur in some infants with in utero-acquired HIV infection after early cART initiation and may be associated with innate immune sex differences.

13.
Cell Rep Med ; 5(4): 101483, 2024 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-38579727

RESUMEN

Immune cell phenotyping frequently detects lineage-unrelated receptors. Here, we report that surface receptors can be transferred from primary macrophages to CD4 T cells and identify the Fcγ receptor CD32 as driver and cargo of this trogocytotic transfer. Filamentous CD32+ nanoprotrusions deposit distinct plasma membrane patches onto target T cells. Transferred receptors confer cell migration and adhesion properties, and macrophage-derived membrane patches render resting CD4 T cells susceptible to infection by serving as hotspots for HIV-1 binding. Antibodies that recognize T cell epitopes enhance CD32-mediated trogocytosis. Such autoreactive anti-HIV-1 envelope antibodies can be found in the blood of HIV-1 patients and, consistently, the percentage of CD32+ CD4 T cells is increased in their blood. This CD32-mediated, antigen-independent cell communication mode transiently expands the receptor repertoire and functionality of immune cells. HIV-1 hijacks this mechanism by triggering the generation of trogocytosis-promoting autoantibodies to gain access to immune cells critical to its persistence.


Asunto(s)
Infecciones por VIH , Seropositividad para VIH , VIH-1 , Humanos , Linfocitos T CD4-Positivos , Receptores de IgG/metabolismo , Autoanticuerpos/metabolismo , Trogocitosis
14.
JCI Insight ; 8(3)2023 02 08.
Artículo en Inglés | MEDLINE | ID: mdl-36602861

RESUMEN

HIV nonprogression despite persistent viremia is rare among adults who are naive to antiretroviral therapy (ART) but relatively common among ART-naive children. Previous studies indicate that ART-naive pediatric slow progressors (PSPs) adopt immune evasion strategies similar to those described in natural hosts of SIV. However, the mechanisms underlying this immunophenotype are not well understood. In a cohort of early-treated infants who underwent analytical treatment interruption (ATI) after 12 months of ART, expression of PD-1 on CD8+ T cells immediately before ATI was the main predictor of slow progression during ATI. PD-1+CD8+ T cell frequency was also negatively correlated with CCR5 and HLA-DR expression on CD4+ T cells and predicted stronger HIV-specific T lymphocyte responses. In the CD8+ T cell compartment of PSPs, we identified an enrichment of stem-like TCF-1+PD-1+ memory cells, whereas pediatric progressors and viremic adults had a terminally exhausted PD-1+CD39+ population. TCF-1+PD-1+ expression on CD8+ T cells was associated with higher proliferative activity and stronger Gag-specific effector functionality. These data prompted the hypothesis that the proliferative burst potential of stem-like HIV-specific cytotoxic cells could be exploited in therapeutic strategies to boost the antiviral response and facilitate remission in infants who received early ART with a preserved and nonexhausted T cell compartment.


Asunto(s)
Infecciones por VIH , Receptor de Muerte Celular Programada 1 , Humanos , Linfocitos T CD4-Positivos , Linfocitos T CD8-positivos , Fenotipo , Receptor de Muerte Celular Programada 1/metabolismo
15.
Med Microbiol Immunol ; 201(2): 201-11, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-22200907

RESUMEN

Antiretroviral treatment directed against HIV is highly effective, yet limited by drug resistance mutations. We hypothesized that CD8 T cells targeting drug-resistant HIV mutants are able to inhibit viral replication in the setting of a failing therapeutic regimen. We evaluated CD8 T-cell responses and mapped epitopes in HIV-infected patients by interferon-gamma Elispot and intracellular cytokine staining. Autologous virus was sequenced by RT-PCR. Viral replication inhibition assays were performed using M184V mutant virus and CD8 T cell lines. CD8 T-cell responses toward the regions of viral drug resistance mutations in Pol are frequent. Focusing on the M184V mutation, A*02:01-YQYVDDLYV and A*02:01-VIYQYVDDLYV were identified as optimal epitopes for the majority of study subjects. Viral replication of M184V HIV mutants was inhibited by CD8 T cell lines in vitro. In case of a failing lamivudine/emtricitabine containing regimen, individuals with a CD8 T-cell response toward M184V had a significant lower viral load than those without a CD8 response (p = 0.005). Two study subjects even achieved an undetectable viral load. Our data suggest that control of M184V mutant virus by CD8 T-cell responses is possible in vitro and in vivo. This control has important implications for therapeutic vaccination strategies.


Asunto(s)
Linfocitos T CD8-positivos/inmunología , Farmacorresistencia Viral , Infecciones por VIH/virología , VIH-1/efectos de los fármacos , VIH-1/inmunología , Mutación Missense , Citocinas/biosíntesis , Ensayo de Immunospot Ligado a Enzimas , Epítopos de Linfocito T/inmunología , Femenino , Infecciones por VIH/tratamiento farmacológico , Humanos , Masculino , ARN Viral/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Análisis de Secuencia de ADN , Replicación Viral
16.
AIDS ; 36(1): 95-105, 2022 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-34581306

RESUMEN

BACKGROUND: Elite controllers are therapy-naive individuals living with HIV capable of spontaneous control of plasma viraemia for at least a year. Although viremic nonprogressors are more common in vertical HIV-infection than in adults' infection, elite control has been rarely characterized in the pediatric population. DESIGN: We analyzed the T-cell immunophenotype and the HIV-specific response by flow cytometry in four pediatric elite controllers (PECs) compared with age-matched nonprogressors (PNPs), progressors and HIV-exposed uninfected (HEUs) adolescents. RESULTS: PECs T-cell populations had lower immune activation and exhaustion levels when compared with progressors, reflected by a more sustained and preserved effector function. The HIV-specific T-cell responses among PECs were characterized by high-frequency Gag-specific CD4+ T-cell activity, and markedly more polyfunctional Gag-specific CD8+ activity, compared with PNPs and progressors. These findings were consistently observed even in the absence of protective HLA-I molecules such as HLA-B∗27/57/81. CONCLUSION: Pediatric elite control is normally achieved after years of infection, and low immune activation in PNPs precedes the increasing ability of CD8+ T-cell responses to achieve immune control of viraemia over the course of childhood, whereas in adults, high immune activation in acute infection predicts subsequent CD8+ T-cell mediated immune control of viremia, and in adult elite controllers, low immune activation is therefore the consequence of the rapid CD8+ T-cell mediated immune control generated after acute infection. This distinct strategy adopted by PECs may help identify pathways that facilitate remission in posttreatment controllers, in whom protective HLA-I molecules are not the main factor.


Asunto(s)
Infecciones por VIH , VIH-1 , Adolescente , Adulto , Linfocitos T CD4-Positivos , Linfocitos T CD8-positivos , Niño , Humanos , Carga Viral , Viremia
17.
Front Immunol ; 13: 922252, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35911762

RESUMEN

NK cells play a pivotal role in viral immunity, utilizing a large array of activating and inhibitory receptors to identify and eliminate virus-infected cells. Killer-cell immunoglobulin-like receptors (KIRs) represent a highly polymorphic receptor family, regulating NK cell activity and determining the ability to recognize target cells. Human leukocyte antigen (HLA) class I molecules serve as the primary ligand for KIRs. Herein, HLA-C stands out as being the dominant ligand for the majority of KIRs. Accumulating evidence indicated that interactions between HLA-C and its inhibitory KIR2DL receptors (KIR2DL1/L2/L3) can drive HIV-1-mediated immune evasion and thus may contribute to the intrinsic control of HIV-1 infection. Of particular interest in this context is the recent observation that HIV-1 is able to adapt to host HLA-C genotypes through Vpu-mediated downmodulation of HLA-C. However, our understanding of the complex interplay between KIR/HLA immunogenetics, NK cell-mediated immune pressure and HIV-1 immune escape is still limited. Therefore, we investigated the impact of specific KIR/HLA-C combinations on the NK cell receptor repertoire and HIV-1 Vpu protein sequence variations of 122 viremic, untreated HIV-1+ individuals. Compared to 60 HIV-1- controls, HIV-1 infection was associated with significant changes within the NK cell receptor repertoire, including reduced percentages of NK cells expressing NKG2A, CD8, and KIR2DS4. In contrast, the NKG2C+ and KIR3DL2+ NK cell sub-populations from HIV-1+ individuals was enlarged compared to HIV-1- controls. Stratification along KIR/HLA-C genotypes revealed a genotype-dependent expansion of KIR2DL1+ NK cells that was ultimately associated with increased binding affinities between KIR2DL1 and HLA-C allotypes. Lastly, our data hinted to a preferential selection of Vpu sequence variants that were associated with HLA-C downmodulation in individuals with high KIR2DL/HLA-C binding affinities. Altogether, our study provides evidence that HIV-1-associated changes in the KIR repertoire of NK cells are to some extent predetermined by host KIR2DL/HLA-C genotypes. Furthermore, analysis of Vpu sequence polymorphisms indicates that differential KIR2DL/HLA-C binding affinities may serve as an additional mechanism how host genetics impact immune evasion by HIV-1.


Asunto(s)
Infecciones por VIH , VIH-1 , Genotipo , Antígenos HLA-C/metabolismo , Antígenos de Histocompatibilidad Clase I/genética , Proteínas del Virus de la Inmunodeficiencia Humana/genética , Humanos , Células Asesinas Naturales , Ligandos , Receptores KIR/metabolismo , Receptores de Células Asesinas Naturales/metabolismo , Proteínas Reguladoras y Accesorias Virales/metabolismo , Proteínas Viroporinas
18.
Front Immunol ; 12: 688436, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34093595

RESUMEN

Background: Adaptive immune responses to structural proteins of the virion play a crucial role in protection against coronavirus disease 2019 (COVID-19). We therefore studied T cell responses against multiple SARS-CoV-2 structural proteins in a large cohort using a simple, fast, and high-throughput approach. Methods: An automated interferon gamma release assay (IGRA) for the Nucleocapsid (NC)-, Membrane (M)-, Spike-C-terminus (SCT)-, and N-terminus-protein (SNT)-specific T cell responses was performed using fresh whole blood from study subjects with convalescent, confirmed COVID-19 (n = 177, more than 200 days post infection), exposed household members (n = 145), and unexposed controls (n = 85). SARS-CoV-2-specific antibodies were assessed using Elecsys® Anti-SARS-CoV-2 (Ro-N-Ig) and Anti-SARS-CoV-2-ELISA (IgG) (EI-S1-IgG). Results: 156 of 177 (88%) previously PCR confirmed cases were still positive by Ro-N-Ig more than 200 days after infection. In T cells, most frequently the M-protein was targeted by 88% seropositive, PCR confirmed cases, followed by SCT (85%), NC (82%), and SNT (73%), whereas each of these antigens was recognized by less than 14% of non-exposed control subjects. Broad targeting of these structural virion proteins was characteristic of convalescent SARS-CoV-2 infection; 68% of all seropositive individuals targeted all four tested antigens. Indeed, anti-NC antibody titer correlated loosely, but significantly with the magnitude and breadth of the SARS-CoV-2-specific T cell response. Age, sex, and body mass index were comparable between the different groups. Conclusion: SARS-CoV-2 seropositivity correlates with broad T cell reactivity of the structural virus proteins at 200 days after infection and beyond. The SARS-CoV-2-IGRA can facilitate large scale determination of SARS-CoV-2-specific T cell responses with high accuracy against multiple targets.


Asunto(s)
COVID-19/inmunología , Interferón gamma/inmunología , SARS-CoV-2/inmunología , Linfocitos T/inmunología , Proteínas Estructurales Virales/inmunología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Anticuerpos Antivirales/sangre , COVID-19/sangre , Femenino , Humanos , Ensayos de Liberación de Interferón gamma , Masculino , Persona de Mediana Edad , Adulto Joven
19.
PLoS One ; 15(9): e0239399, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32946499

RESUMEN

HIV-1 infection exhibits a significant sex bias. This study aimed at identifying and examining lymphocyte associated sex differences in HIV-1 pathogenesis using a data-driven approach. To select targets for investigating sex differences in lymphocytes, data of microarray experiments and literature mining were integrated. Data from three large-scale microarray experiments were obtained from NCBI/GEO and screened for sex differences in gene expression. Literature mining was employed to identify sex biased genes in the microarray data, which were relevant to HIV-1 pathogenesis and lymphocyte biology. Sex differences in gene expression of selected genes were investigated by RT-qPCR and flowcytometry in healthy individuals and persons living with HIV-1. A significant and consistent sex bias was identified in 31 genes, the majority of which were related to immunity and expressed at higher levels in women. Using literature mining, three genes (DPP4, FCGR1A and SOCS3) were selected for analysis by qPCR because of their relevance to HIV, as well as, B and T cell biology. DPP4 exhibited the most significant sex bias in mRNA expression (p = 0.00029). Therefore, its expression was further analyzed on B and T cells using flowcytometry. In HIV-1 infected controllers and healthy individuals, frequencies of CD4+DPP4+ T cells were higher in women compared to men (p = 0.037 and p = 0.027). In women, CD4 T cell counts correlated with a predominant decreased in DPP4+CD4+ T cells (p = 0.0032). Sex differences in DPP4 expression abrogated in progressive HIV-1 infection. In conclusion, we found sex differences in the pathobiology of T cells in HIV-1 infection using a data-driven approach. Our results indicate that DPP4 expression on CD4+ T cells might contribute to the immunological sex differences observed in chronic HIV­1 infection.


Asunto(s)
Linfocitos T CD4-Positivos/citología , Minería de Datos , Dipeptidil Peptidasa 4/metabolismo , Infecciones por VIH/genética , Infecciones por VIH/inmunología , VIH-1/fisiología , Análisis de Secuencia por Matrices de Oligonucleótidos , Adulto , Linfocitos T CD4-Positivos/metabolismo , Recuento de Células , Progresión de la Enfermedad , Femenino , Humanos , Masculino , Distribución por Sexo
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