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1.
J Antimicrob Chemother ; 71(11): 3185-3194, 2016 11.
Artículo en Inglés | MEDLINE | ID: mdl-27494916

RESUMEN

BACKGROUND: Approximately 1.5 million HIV-positive women become pregnant annually. Without treatment, up to 45% will transmit HIV to their infants, primarily through breastfeeding. These numbers highlight that HIV acquisition is a major health concern for women and children globally. They also emphasize the urgent need for novel approaches to prevent HIV acquisition that are safe, effective and convenient to use by women and children in places where they are most needed. METHODS: 4'-Ethynyl-2-fluoro-2'-deoxyadenosine, a potent NRTI with low cytotoxicity, was administered orally to NOD/SCID/γc-/- mice and to bone marrow/liver/thymus (BLT) humanized mice, a preclinical model of HIV infection. HIV inhibitory activity in serum, cervicovaginal secretions and saliva was evaluated 4 h after administration. 4'-Ethynyl-2-fluoro-2'-deoxyadenosine's ability to prevent vaginal and oral HIV transmission was evaluated using highly relevant transmitted/founder viruses in BLT mice. RESULTS: Strong HIV inhibitory activity in serum, cervicovaginal secretions and saliva obtained from animals after a single oral dose of 4'-ethynyl-2-fluoro-2'-deoxyadenosine (10 mg/kg) demonstrated efficient drug penetration into relevant mucosal sites. A single daily oral dose of 4'-ethynyl-2-fluoro-2'-deoxyadenosine resulted in efficient prevention of vaginal and oral HIV transmission after multiple high-dose exposures to transmitted/founder viruses in BLT humanized mice. CONCLUSIONS: Our data demonstrated that 4'-ethynyl-2-fluoro-2'-deoxyadenosine efficiently prevents both vaginal and oral HIV transmission. Together with 4'-ethynyl-2-fluoro-2'-deoxyadenosine's relatively low toxicity and high potency against drug-resistant HIV strains, these data support further clinical development of 4'-ethynyl-2-fluoro-2'-deoxyadenosine as a potential pre-exposure prophylaxis agent to prevent HIV transmission in women and their infants.


Asunto(s)
Fármacos Anti-VIH/administración & dosificación , Desoxiadenosinas/administración & dosificación , Transmisión de Enfermedad Infecciosa/prevención & control , Infecciones por VIH/prevención & control , Boca/virología , Profilaxis Pre-Exposición/métodos , Vagina/virología , Animales , Secreciones Corporales/virología , Modelos Animales de Enfermedad , Femenino , Infecciones por VIH/transmisión , Estudios Longitudinales , Ratones , Ratones SCID
2.
Blood Cancer Discov ; 4(2): 106-117, 2023 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-36511813

RESUMEN

Patients with multiple myeloma (MM) mount suboptimal neutralizing antibodies (nAb) following 2 doses of SARS-CoV-2 mRNA vaccines. Currently, circulating SARS-CoV-2 variants of concern (VOC) carry the risk of breakthrough infections. We evaluated immune recognition of current VOC including BA.1, BA.2, and BA.5 in 331 racially representative patients with MM following 2 or 3 doses of mRNA vaccines. The third dose increased nAbs against WA1 in 82%, but against BA variants in only 33% to 44% of patients. Vaccine-induced nAbs correlated with receptor-binding domain (RBD)-specific class-switched memory B cells. Vaccine-induced spike-specific T cells were detected in patients without seroconversion and cross-recognized variant-specific peptides but were predominantly CD4+ T cells. Detailed clinical/immunophenotypic analysis identified features correlating with nAb/B/T-cell responses. Patients who developed breakthrough infections following 3 vaccine doses had lower live-virus nAbs, including against VOC. Patients with MM remain susceptible to SARS-CoV-2 variants following 3 vaccine doses and should be prioritized for emerging approaches to elicit variant-nAb and CD8+ T cells. SIGNIFICANCE: Three doses of SARS-CoV-2 mRNA vaccines fail to yield detectable VOC nAbs in nearly 60% and spike-specific CD8+ T cells in >80% of myeloma patients. Patients who develop breakthrough infections following vaccination have low levels of live-virus nAb. This article is highlighted in the In This Issue feature, p. 101.


Asunto(s)
COVID-19 , Mieloma Múltiple , Humanos , SARS-CoV-2 , Infección Irruptiva , COVID-19/prevención & control , Linfocitos T CD8-positivos , Vacunas de ARNm , Anticuerpos Neutralizantes
3.
JCI Insight ; 7(8)2022 04 22.
Artículo en Inglés | MEDLINE | ID: mdl-35271506

RESUMEN

The persistence of virally infected cells as reservoirs despite effective antiretroviral therapy is a major barrier to an HIV/SIV cure. These reservoirs are predominately contained within cells present in the B cell follicles (BCFs) of secondary lymphoid tissues, a site that is characteristically difficult for most cytolytic antiviral effector cells to penetrate. Here, we identified a population of NK cells in macaque lymph nodes that expressed BCF-homing receptor CXCR5 and accumulated within BCFs during chronic SHIV infection. These CXCR5+ follicular NK cells exhibited an activated phenotype coupled with heightened effector functions and a unique transcriptome characterized by elevated expression of cytolytic mediators (e.g., perforin and granzymes, LAMP-1). CXCR5+ NK cells exhibited high expression of FcγRIIa and FcγRIIIa, suggesting a potential for elevated antibody-dependent effector functionality. Consistently, accumulation of CXCR5+ NK cells showed a strong inverse association with plasma viral load and the frequency of germinal center follicular Th cells that comprise a significant fraction of the viral reservoir. Moreover, CXCR5+ NK cells showed increased expression of transcripts associated with IL-12 and IL-15 signaling compared with the CXCR5- subset. Indeed, in vitro treatment with IL-12 and IL-15 enhanced the proliferation of CXCR5+ granzyme B+ NK cells. Our findings suggest that follicular homing NK cells might be important in immune control of chronic SHIV infection, and this may have important implications for HIV cure strategies.


Asunto(s)
Infecciones por VIH , Interleucina-15 , Humanos , Interleucina-12/metabolismo , Interleucina-15/metabolismo , Células Asesinas Naturales , Ganglios Linfáticos , Receptores CXCR5/metabolismo
4.
J Clin Oncol ; 40(26): 3057-3064, 2022 09 10.
Artículo en Inglés | MEDLINE | ID: mdl-35259002

RESUMEN

PURPOSE: Vaccine-induced neutralizing antibodies (nAbs) play a critical role in protection from SARS CoV-2. Patients with B-cell malignancies including myeloma are at increased risk of COVID-19-related mortality and exhibit variable serologic response to the vaccine. The capacity of vaccine-induced antibodies in these patients to neutralize SARS CoV-2 or its variants is not known. METHODS: Sera from 238 patients with multiple myeloma (MM) undergoing SARS CoV-2 vaccination were analyzed. Antibodies against the SARS CoV-2 spike receptor-binding domain (RBD) and viral nucleocapsid were measured to detect serologic response to vaccine and environmental exposure to the virus. The capacity of antibodies to neutralize virus was quantified using pseudovirus neutralization assay and live virus neutralization against the initial SARS CoV-2 strain and the B1.617.2 (Delta) variant. RESULTS: Vaccine-induced nAbs are detectable at much lower rates (54%) than estimated in previous seroconversion studies in MM, which did not monitor viral neutralization. In 33% of patients, vaccine-induced antispike RBD antibodies lack detectable neutralizing capacity, including against the B1.617.2 variant. Induction of nAbs is affected by race, disease, and treatment-related factors. Patients receiving mRNA1273 vaccine (Moderna) achieved significantly greater induction of nAbs compared with those receiving BNT162b2 (Pfizer; 67% v 48%, P = .006). CONCLUSION: These data show that vaccine-induced antibodies in several patients with MM lack detectable virus-neutralizing activity. Vaccine-mediated induction of nAbs is affected by race, disease, vaccine, and treatment characteristics. These data have several implications for the emerging application of booster vaccines in immunocompromised hosts.


Asunto(s)
Vacunas contra la COVID-19 , COVID-19 , Mieloma Múltiple , Vacuna nCoV-2019 mRNA-1273 , Anticuerpos Neutralizantes , Anticuerpos Antivirales , Vacuna BNT162 , COVID-19/prevención & control , Vacunas contra la COVID-19/efectos adversos , Humanos , Pruebas de Neutralización , SARS-CoV-2 , Glicoproteína de la Espiga del Coronavirus , Vacunación
5.
medRxiv ; 2022 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-35018383

RESUMEN

PURPOSE: We investigated SARS-CoV-2 mRNA vaccine-induced binding and live-virus neutralizing antibody response in NSCLC patients to the SARS-CoV-2 wild type strain and the emerging Delta and Omicron variants. METHODS: 82 NSCLC patients and 53 healthy adult volunteers who received SARS-CoV-2 mRNA vaccines were included in the study. Blood was collected longitudinally, and SARS-CoV-2-specific binding and live-virus neutralization response to 614D (WT), B.1.617.2 (Delta), B.1.351 (Beta) and B.1.1.529 (Omicron) variants were evaluated by Meso Scale Discovery (MSD) assay and Focus Reduction Neutralization Assay (FRNT) respectively. We determined the longevity and persistence of vaccine-induced antibody response in NSCLC patients. The effect of vaccine-type, age, gender, race and cancer therapy on the antibody response was evaluated. RESULTS: Binding antibody titer to the mRNA vaccines were lower in the NSCLC patients compared to the healthy volunteers (P=<0.0001). More importantly, NSCLC patients had reduced live-virus neutralizing activity compared to the healthy vaccinees (P=<0.0001). Spike and RBD-specific binding IgG titers peaked after a week following the second vaccine dose and declined after six months (P=<0.001). While patients >70 years had lower IgG titers (P=<0.01), patients receiving either PD-1 monotherapy, chemotherapy or a combination of both did not have a significant impact on the antibody response. Binding antibody titers to the Delta and Beta variants were lower compared to the WT strain (P=<0.0001). Importantly, we observed significantly lower FRNT50 titers to Delta (6-fold), and Omicron (79-fold) variants (P=<0.0001) in NSCLC patients. CONCLUSIONS: Binding and live-virus neutralizing antibody titers to SARS-CoV-2 mRNA vaccines in NSCLC patients were lower than the healthy vaccinees, with significantly lower live-virus neutralization of B.1.617.2 (Delta), and more importantly, the B.1.1.529 (Omicron) variant compared to the wild-type strain. These data highlight the concern for cancer patients given the rapid spread of SARS-CoV-2 Omicron variant.

6.
J Clin Oncol ; 40(33): 3808-3816, 2022 11 20.
Artículo en Inglés | MEDLINE | ID: mdl-35759727

RESUMEN

PURPOSE: To examine COVID-19 mRNA vaccine-induced binding and neutralizing antibody responses in patients with non-small-cell lung cancer (NSCLC) to SARS-CoV-2 614D (wild type [WT]) strain and variants of concern after the primary 2-dose and booster vaccination. METHODS: Eighty-two patients with NSCLC and 53 healthy volunteers who received SARS-CoV-2 mRNA vaccines were included in the study. Blood was collected longitudinally, and SARS-CoV-2-specific binding and neutralizing antibody responses were evaluated by Meso Scale Discovery assay and live virus Focus Reduction Neutralization Assay, respectively. RESULTS: A majority of patients with NSCLC generated binding and neutralizing antibody titers comparable with the healthy vaccinees after mRNA vaccination, but a subset of patients with NSCLC (25%) made poor responses, resulting in overall lower (six- to seven-fold) titers compared with the healthy cohort (P = < .0001). Although patients age > 70 years had lower immunoglobulin G titers (P = < .01), patients receiving programmed death-1 monotherapy, chemotherapy, or a combination of both did not have a significant impact on the antibody response. Neutralizing antibody titers to the B.1.617.2 (Delta), B.1.351 (Beta), and in particular, B.1.1.529 (Omicron) variants were significantly lower (P = < .0001) compared with the 614D (WT) strain. Booster vaccination led to a significant increase (P = .0001) in the binding and neutralizing antibody titers to the WT and Omicron variant. However, 2-4 months after the booster, we observed a five- to seven-fold decrease in neutralizing titers to WT and Omicron viruses. CONCLUSION: A subset of patients with NSCLC responded poorly to the SARS-CoV-2 mRNA vaccination and had low neutralizing antibodies to the B.1.1.529 Omicron variant. Booster vaccination increased binding and neutralizing antibody titers to Omicron, but antibody titers declined after 3 months. These data highlight the concern for patients with cancer given the rapid spread of SARS-CoV-2 Omicron variant.


Asunto(s)
COVID-19 , Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Humanos , Anciano , Vacunas contra la COVID-19 , Formación de Anticuerpos , SARS-CoV-2 , Carcinoma de Pulmón de Células no Pequeñas/terapia , Neoplasias Pulmonares/terapia , COVID-19/prevención & control , Anticuerpos Antivirales , Inmunización , Vacunación , Anticuerpos Neutralizantes , ARN Mensajero , Vacunas de ARNm
7.
Am J Reprod Immunol ; 84(1): e13246, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32301548

RESUMEN

PROBLEM: The effects of HIV on the gastrointestinal tract (GIT), including CD4 depletion, epithelial disruption, and collagen deposition, are well documented and only partially reversed by combination antiretroviral therapy (cART). However, the effects of HIV on the female reproductive tract (FRT) are poorly understood, and most studies have focused on ectocervix and vagina without assessing the upper tract. Here, we investigated CD4+ T-cell frequency, phenotype, and HIV-specific T-cell responses in the endocervix and endometrium of HIV-infected women, comparing these tissues to the GIT. METHOD OF STUDY: Mucosal samples and blood were obtained from 18 women: four who were HIV-positive and not on cART for at least 3 years prior to sampling, including two natural controllers (viral load [VL] undetectable and CD4 >350); nine women on cART with low to undetectable VL; and five HIV-uninfected women. Mucosal samples included terminal ileum, sigmoid colon, endocervical cytobrush, endocervical curettage, and endometrial biopsy. T-cell frequency, phenotypes, and HIV-specific T-cell responses were analyzed by multiparameter flow cytometry. RESULTS: T-cell activation, measured by CD38/HLA-DR co-expression, remained significantly elevated in endometrium following cART, but was lower in gastrointestinal tissues. HIV-specific CD8+ T-cell responses were detected in ileum, colon, and endometrial tissues of women both on and off cART, and were of higher magnitude on those not on cART. CONCLUSION: Our findings reveal differences in CD4+ T-cell frequencies, immune activation, and HIV-specific T-cell responses between the gastrointestinal and reproductive tracts, and highlight differences between HIV controllers and women on cART.


Asunto(s)
Linfocitos T CD4-Positivos/inmunología , Genitales Femeninos/inmunología , Infecciones por VIH/inmunología , VIH-1/fisiología , Mucosa Intestinal/inmunología , Adulto , Terapia Antirretroviral Altamente Activa , Células Cultivadas , Femenino , Infecciones por VIH/tratamiento farmacológico , Humanos , Inmunidad Mucosa , Inmunofenotipificación , Activación de Linfocitos , Persona de Mediana Edad , Especificidad de Órganos
8.
JCI Insight ; 5(14)2020 07 23.
Artículo en Inglés | MEDLINE | ID: mdl-32554933

RESUMEN

Mycobacterium tuberculosis-specific (M. tuberculosis-specific) T cell responses associated with immune control during asymptomatic latent tuberculosis infection (LTBI) remain poorly understood. Using a nonhuman primate aerosol model, we studied the kinetics, phenotypes, and functions of M. tuberculosis antigen-specific T cells in peripheral and lung compartments of M. tuberculosis-infected asymptomatic rhesus macaques by longitudinally sampling blood and bronchoalveolar lavage, for up to 24 weeks postinfection. We found substantially higher frequencies of M. tuberculosis-specific effector and memory CD4+ and CD8+ T cells producing IFN-γ in the airways compared with peripheral blood, and these frequencies were maintained throughout the study period. Moreover, M. tuberculosis-specific IL-17+ and IL-17+IFN-γ+ double-positive T cells were present in the airways but were largely absent in the periphery, suggesting that balanced mucosal Th1/Th17 responses are associated with LTBI. The majority of M. tuberculosis-specific CD4+ T cells that homed to the airways expressed the chemokine receptor CXCR3 and coexpressed CCR6. Notably, CXCR3+CD4+ cells were found in granulomatous and nongranulomatous regions of the lung and inversely correlated with M. tuberculosis burden. Our findings provide insights into antigen-specific T cell responses associated with asymptomatic M. tuberculosis infection that are relevant for developing better strategies to control TB.


Asunto(s)
Tuberculosis Latente/genética , Pulmón/inmunología , Receptores CCR6/genética , Receptores CXCR3/genética , Tuberculosis Pulmonar/genética , Animales , Antígenos Bacterianos/genética , Antígenos Bacterianos/inmunología , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD4-Positivos/microbiología , Linfocitos T CD8-positivos/inmunología , Linfocitos T CD8-positivos/microbiología , Modelos Animales de Enfermedad , Femenino , Humanos , Interleucina-17/genética , Interleucina-17/inmunología , Tuberculosis Latente/inmunología , Tuberculosis Latente/microbiología , Tuberculosis Latente/patología , Pulmón/microbiología , Pulmón/patología , Macaca mulatta , Mycobacterium tuberculosis/inmunología , Mycobacterium tuberculosis/patogenicidad , Células TH1/inmunología , Células TH1/microbiología , Células Th17/inmunología , Células Th17/microbiología , Tuberculosis Pulmonar/inmunología , Tuberculosis Pulmonar/microbiología , Tuberculosis Pulmonar/patología
9.
J Clin Invest ; 130(10): 5171-5179, 2020 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-32544085

RESUMEN

While the advent of combination antiretroviral therapy (ART) has significantly improved survival, tuberculosis (TB) remains the leading cause of death in the HIV-infected population. We used Mycobacterium tuberculosis/simian immunodeficiency virus-coinfected (M. tuberculosis/SIV-coinfected) macaques to model M. tuberculosis/HIV coinfection and study the impact of ART on TB reactivation due to HIV infection. Although ART significantly reduced viral loads and increased CD4+ T cell counts in blood and bronchoalveolar lavage (BAL) samples, it did not reduce the relative risk of SIV-induced TB reactivation in ART-treated macaques in the early phase of treatment. CD4+ T cells were poorly restored specifically in the lung interstitium, despite their significant restoration in the alveolar compartment of the lung as well as in the periphery. IDO1 induction in myeloid cells in the inducible bronchus-associated lymphoid tissue (iBALT) likely contributed to dysregulated T cell homing and impaired lung immunity. Thus, although ART was indispensable for controlling viral replication, restoring CD4+ T cells, and preventing opportunistic infection, it appeared inadequate in reversing the clinical signs of TB reactivation during the relatively short duration of ART administered in this study. This finding warrants the modeling of concurrent treatment of TB and HIV to potentially reduce the risk of reactivation of TB due to HIV to inform treatment strategies in patients with M. tuberculosis/HIV coinfection.


Asunto(s)
Antirretrovirales/uso terapéutico , Coinfección/tratamiento farmacológico , Tuberculosis Latente/complicaciones , Síndrome de Inmunodeficiencia Adquirida del Simio/complicaciones , Síndrome de Inmunodeficiencia Adquirida del Simio/tratamiento farmacológico , Animales , Fármacos Anti-VIH/uso terapéutico , Terapia Antirretroviral Altamente Activa , Carga Bacteriana , Linfocitos T CD4-Positivos/efectos de los fármacos , Linfocitos T CD4-Positivos/inmunología , Modelos Animales de Enfermedad , Infecciones por VIH/complicaciones , Infecciones por VIH/tratamiento farmacológico , Humanos , Tuberculosis Latente/microbiología , Tuberculosis Latente/patología , Macaca mulatta , Síndrome de Inmunodeficiencia Adquirida del Simio/virología , Virus de la Inmunodeficiencia de los Simios , Carga Viral/efectos de los fármacos
10.
Artículo en Inglés | MEDLINE | ID: mdl-19822735

RESUMEN

The reverse transcriptase (RT) enzyme of HIV type 1 (HIV-1) is largely targeted by the host immune selection pressure and would differ in the anatomical compartments, thereby having a drastic impact on viral quasi-species evolution. The HIV-1 RT region sequenced from plasma and genital secretions of 8 antiretroviral treatment (ART)-naive females was analyzed for the pattern of amino acid mutations and the ratio of synonymous and nonsynonymous substitutions to determine whether it is under different selection pressure in both the compartments. Phylogenetic and mutational analysis of the HIV-1 RT in plasma and genital secretions of HIV-1-infected ART-naive females showed limited variation likely reflecting the absence of differential selection pressure and therefore genetic variation in these compartments.


Asunto(s)
Infecciones por VIH/virología , Transcriptasa Inversa del VIH/genética , VIH-1/genética , ARN Viral/genética , Adulto , Algoritmos , Recuento de Linfocito CD4 , Codón , Bases de Datos de Ácidos Nucleicos , Femenino , Infecciones por VIH/enzimología , Infecciones por VIH/transmisión , Transcriptasa Inversa del VIH/análisis , Transcriptasa Inversa del VIH/sangre , Transcriptasa Inversa del VIH/química , VIH-1/clasificación , VIH-1/enzimología , Humanos , India , Mutación , Filogenia , Reacción en Cadena de la Polimerasa , ARN Viral/análisis , ARN Viral/sangre , Alineación de Secuencia , Frotis Vaginal , Adulto Joven
11.
Front Immunol ; 10: 3053, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-32010135

RESUMEN

Mucosa-associated invariant T (MAIT) cells are recently characterized as a novel subset of innate-like T cells that recognize microbial metabolites as presented by the MHC-1b-related protein MR1. The significance of MAIT cells in anti-bacterial defense is well-understood but not clear in viral infections such as SIV/HIV infection. Here we studied the phenotype, distribution, and function of MAIT cells and their association with plasma viral levels during chronic SHIV infection in rhesus macaques (RM). Two groups of healthy and chronic SHIV-infected macaques were characterized for MAIT cells in blood and mucosal tissues. Similar to human, we found a significant fraction of macaque T cells co-expressing MAIT cell markers CD161 and TCRVα-7.2 that correlated directly with macaque MR1 tetramer. These cells displayed memory phenotype and expressed high levels of IL-18R, CCR6, CD28, and CD95. During chronic infection, the frequency of MAIT cells are enriched in the blood but unaltered in the rectum; both blood and rectal MAIT cells displayed higher proliferative and cytotoxic phenotype post-SHIV infection. The frequency of MAIT cells in blood and rectum correlated inversely with plasma viral RNA levels and correlated directly with total CD4 T cells. MAIT cells respond to microbial products during chronic SHIV infection and correlated positively with serum immunoreactivity to flagellin levels. Tissue distribution analysis of MAIT cells during chronic infection showed significant enrichment in the non-lymphoid tissues (lung, rectum, and liver) compared to lymphoid tissues (spleen and LN), with higher levels of tissue-resident markers CD69 and CD103. Exogenous in vitro cytokine treatments during chronic SHIV infection revealed that IL-7 is important for the proliferation of MAIT cells, but IL-12 and IL-18 are important for their cytolytic function. Overall our results demonstrated that MAIT cells are enriched in blood but unaltered in the rectum during chronic SHIV infection, which displayed proliferative and functional phenotype that inversely correlated with SHIV plasma viral RNA levels. Treatment such as combined cytokine treatments could be beneficial for enhancing functional MAIT cells during chronic HIV infection in vivo.


Asunto(s)
Susceptibilidad a Enfermedades , Infecciones por VIH/etiología , Infecciones por VIH/metabolismo , VIH/inmunología , Células T Invariantes Asociadas a Mucosa/fisiología , Síndrome de Inmunodeficiencia Adquirida del Simio/etiología , Síndrome de Inmunodeficiencia Adquirida del Simio/metabolismo , Virus de la Inmunodeficiencia de los Simios/inmunología , Animales , Biomarcadores , Linfocitos T CD8-positivos/inmunología , Linfocitos T CD8-positivos/metabolismo , Interacciones Huésped-Patógeno/genética , Interacciones Huésped-Patógeno/inmunología , Humanos , Recuento de Linfocitos , Macaca mulatta , Subgrupos de Linfocitos T/inmunología , Subgrupos de Linfocitos T/metabolismo
12.
J Microbiol Biotechnol ; 18(10): 1722-8, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18955826

RESUMEN

The natural course of chronic hepatitis B (CH-B) virus infection is reportedly variable, and the long-term outcomes in hepatitis B e antigen (HBeAg)-negative chronic hepatitis B infection are distinct from HBeAg-positive chronic hepatitis. However, the molecular virological factors that contribute to the progression of liver disease in the south Indian setting remain largely unclear. We prospectively studied 679 consecutive patients for HBsAg, HBeAg, anti-HBeAg, and HBV DNA by qualitative PCR. Randomly selected samples were subjected to bidirectional sequencing to reveal core/precore variants. Of the total 679 chronic HBV cases investigated, 23% (154/679) were replicative HBV carriers. Furthermore, amongst the 560 HBV DNA samples analyzed, 26% (146/560) were viremic. Among the 154 HBeAg positive cases, HBV DNA was positive in 118 cases (77%), significantly (p<0.001) higher than the anti-HBe positive (7%) (28/406) cases. Significant increase in liver disease (p<0.01) with ALT enzyme elevation (p<0.001) was observed in both HBe and anti-HBe viremic cases. Interestingly, low frequencies of mutations were seen in the precore region of the HBV strains studied. HBV precore and core promoter variants were less often detected in subjects with "e" negative chronic HBV infection and, therefore, may not have a prognostic role in determining liver disease sequelae in this part of tropical India.


Asunto(s)
Portador Sano/inmunología , Anticuerpos contra la Hepatitis B/sangre , Antígenos del Núcleo de la Hepatitis B/genética , Antígenos e de la Hepatitis B/inmunología , Virus de la Hepatitis B/genética , Hepatitis B Crónica/inmunología , Mutación , Adulto , Anciano , Portador Sano/virología , Femenino , Antígenos de Superficie de la Hepatitis B/genética , Antígenos e de la Hepatitis B/genética , Virus de la Hepatitis B/inmunología , Hepatitis B Crónica/virología , Humanos , India , Masculino , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa , Estudios Prospectivos , Adulto Joven
13.
Curr HIV Res ; 16(4): 302-314, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30543175

RESUMEN

BACKGROUND: Anti-viral cytokine expressions by cytotoxic T-cells and lower activation rates have been reported to correlate with suppressed HIV replication in long-term non-progressors (LTNP). Immune mechanisms underlying disease non-progression in LTNP might vary with HIV-1 subtype and geographical locations. OBJECTIVE: This study evaluates cytokine expression and T-cells activation in relation to disease non-progression in LTNP. METHODS: HIV-1 Subtype C infected LTNP (n=20) and progressors (n=15) were enrolled and flowcytometry assays were performed to study HIV-specific CD8 T-cells expressing IL-2, IFN-γ, TNF-α and MIP-1ß against gag and env peptides. CD4+ T-cell activation was evaluated by surface expression of HLADR and CD38. RESULTS: Proportions of cytokines studied did not differ significantly between LTNP and progressors, while contrasting correlations with disease progression markers were observed in LTNP. CD4+ T-cell activation rates were significantly lower in LTNP compared to progressors which indicate the potential role of T-cell activation rates in disease non-progression in LTNP. CONCLUSION: LTNP and progressors showed similar CD8+ T-cell responses, but final conclusions can be drawn only by comparing multiple immune factors in larger LTNP cohort with HIV-1 infected individuals at various levels of disease progression. A possible role of HIV-1 subtype variation and ethnic differences in addition to host-genetic and viral factors cannot be ruled out.


Asunto(s)
Linfocitos T CD8-positivos/inmunología , Infecciones por VIH/patología , Sobrevivientes de VIH a Largo Plazo , VIH-1/inmunología , Activación de Linfocitos , ADP-Ribosil Ciclasa 1/análisis , Adulto , Estudios Transversales , Citocinas/metabolismo , Femenino , Citometría de Flujo , Genotipo , VIH-1/clasificación , VIH-1/genética , Antígenos HLA-DR/análisis , Humanos , India , Masculino , Glicoproteínas de Membrana/análisis , Productos del Gen env del Virus de la Inmunodeficiencia Humana/inmunología , Productos del Gen gag del Virus de la Inmunodeficiencia Humana/inmunología
14.
PLoS One ; 11(7): e0159517, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27438728

RESUMEN

BACKGROUND: The nucleoside reverse transcriptase inhibitor (NRTI) 4'-ethynyl-2-fluoro-2'-deoxyadenosine (EFdA) in preclinical development exhibits improved safety and antiviral activity profiles with minimal drug resistance compared to approved NRTIs. However, the systemic antiviral efficacy of EFdA has not been fully evaluated. In this study, we utilized bone marrow/liver/thymus (BLT) humanized mice to investigate the systemic effect of EFdA treatment on HIV replication and CD4+ T cell depletion in the peripheral blood (PB) and tissues. In particular, we performed a comprehensive analysis of the female reproductive tract (FRT) and gastrointestinal (GI) tract, major sites of transmission, viral replication, and CD4+ T cell depletion and where some current antiretroviral drugs have a sub-optimal effect. RESULTS: EFdA treatment resulted in reduction of HIV-RNA in PB to undetectable levels in the majority of treated mice by 3 weeks post-treatment. HIV-RNA levels in cervicovaginal lavage of EFdA-treated BLT mice also declined to undetectable levels demonstrating strong penetration of EFdA into the FRT. Our results also demonstrate a strong systemic suppression of HIV replication in all tissues analyzed. In particular, we observed more than a 2-log difference in HIV-RNA levels in the GI tract and FRT of EFdA-treated BLT mice compared to untreated HIV-infected control mice. In addition, HIV-RNA was also significantly lower in the lymph nodes, liver, lung, spleen of EFdA-treated BLT mice compared to untreated HIV-infected control mice. Furthermore, EFdA treatment prevented the depletion of CD4+ T cells in the PB, mucosal tissues and lymphoid tissues. CONCLUSION: Our findings indicate that EFdA is highly effective in controlling viral replication and preserving CD4+ T cells in particular with high efficiency in the GI and FRT tract. Thus, EFdA represents a strong potential candidate for further development as a part of antiretroviral therapy regimens.


Asunto(s)
Fármacos Anti-VIH/administración & dosificación , Desoxiadenosinas/administración & dosificación , Infecciones por VIH/tratamiento farmacológico , VIH-1/efectos de los fármacos , Infecciones del Sistema Genital/tratamiento farmacológico , Animales , Médula Ósea/efectos de los fármacos , Médula Ósea/patología , Médula Ósea/virología , Linfocitos T CD4-Positivos/efectos de los fármacos , Modelos Animales de Enfermedad , Femenino , Tracto Gastrointestinal/efectos de los fármacos , Tracto Gastrointestinal/virología , Genes Transgénicos Suicidas , Infecciones por VIH/patología , Infecciones por VIH/virología , Transcriptasa Inversa del VIH/antagonistas & inhibidores , VIH-1/patogenicidad , Humanos , Hígado/efectos de los fármacos , Hígado/patología , Hígado/virología , Masculino , Ratones , Infecciones del Sistema Genital/patología , Infecciones del Sistema Genital/virología , Inhibidores de la Transcriptasa Inversa/administración & dosificación , Timo/efectos de los fármacos , Timo/virología , Replicación Viral/efectos de los fármacos
15.
Am J Reprod Immunol ; 76(2): 137-48, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-27401588

RESUMEN

PROBLEM: There is little information regarding the impact of the intrauterine device on immune parameters of the upper female reproductive tract related to risk of HIV acquisition. METHOD OF STUDY: We collected cervical and endometrial samples from women using the hormonal intrauterine device to study its effects on endocervical cytokines/chemokine concentrations, phenotypic markers of T cells, responses of endometrial T cells to activation, and alterations of endometrial cellular infiltrates. RESULTS: Hormonal intrauterine device use was associated with: increased concentrations of inflammatory cytokines/chemokines (endocervix); increased coexpression of CXCR4 and CCR5 (endocervix and endometrium); increased coexpression of CD38 and HLADR (endocervix and endometrium); increased intracellular IL-10 production after T-cell stimulation (endometrium); and increased density of T cells, most notably regulatory T cells (endometrium). CONCLUSION: Hormonal intrauterine device use resulted in both inflammatory and immunosuppressive alterations. Further research is needed to determine the significance of these changes for HIV risk.


Asunto(s)
Cuello del Útero/inmunología , Sistemas de Liberación de Medicamentos/efectos adversos , Endometrio/inmunología , Levonorgestrel/administración & dosificación , Adulto , Estudios Transversales , Femenino , Infecciones por VIH/inmunología , Antígenos HLA-DR/inmunología , Humanos , Interleucina-10/inmunología , Levonorgestrel/efectos adversos , Persona de Mediana Edad , Receptores CCR4/inmunología , Receptores CCR5/inmunología , Factores de Riesgo , Linfocitos T/inmunología
16.
PLoS One ; 10(7): e0129769, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26177352

RESUMEN

Intravaginal anti-HIV microbicides could provide women with a self-controlled means for HIV prevention, but results from clinical trials have been largely disappointing. We postulated that unrecognized effects of intravaginal gels on the upper female reproductive tract might contribute to the lower-than-expected efficacy of HIV microbicides. Our objective was to study the effects of intravaginal gels on the immune microenvironment of the cervix and uterus. In this randomized crossover study, 27 healthy female volunteers used a nightly application of intravaginal nonoxynol-9 (N9) gel as a "failed" microbicide or the universal placebo gel (UPG) as a "safe" gel (intervention cycles), or nothing (control cycle) from the end of menses to the mid-luteal phase. At a specific time-point following ovulation, all participants underwent sample collection for measurements of T-cell phenotypes, gene expression, and cytokine/chemokine protein concentrations from 3 anatomic sites above the vagina: the cervical transformation zone, the endocervix and the endometrium. We used hierarchical statistical models to estimate mean (95% CI) intervention effects, for N9 and UPG relative to control. Exposure to N9 gel and UPG generated a common "harm signal" that included transcriptional up-regulation of inflammatory genes chemokine (C-C motif) ligand 20 (macrophage inflammatory factor-3alpha) and interleukin 8 in the cervix, decreased protein concentrations of secretory leukocyte protease inhibitor, and transcriptional up-regulation of inflammatory mediators glycodelin-A and osteopontin in the endometrium. These results need to be replicated with a larger sample, but underscore the need to consider the effects of microbicide agents and gel excipients on the upper female reproductive tract in studies of vaginal microbicides.


Asunto(s)
Fármacos Anti-VIH/efectos adversos , Cuello del Útero/efectos de los fármacos , Cuello del Útero/inmunología , Nonoxinol/efectos adversos , Útero/efectos de los fármacos , Útero/inmunología , Administración Intravaginal , Adulto , Fármacos Anti-VIH/administración & dosificación , Microambiente Celular/efectos de los fármacos , Microambiente Celular/inmunología , Cuello del Útero/metabolismo , Estudios Cruzados , Femenino , Geles , Humanos , Inflamación/inducido químicamente , Inflamación/genética , Inflamación/inmunología , Nonoxinol/administración & dosificación , Fenotipo , Placebos , Linfocitos T/efectos de los fármacos , Linfocitos T/inmunología , Transcriptoma/efectos de los fármacos , Útero/metabolismo , Adulto Joven
17.
Am J Reprod Immunol ; 71(2): 95-108, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24313954

RESUMEN

PROBLEM: The goal of this study was to investigate the phenotype and functional responsiveness of CD4(+) and CD8(+) T-cells in the upper reproductive tract of healthy premenopausal women. The lower reproductive tract is frequently studied as a site of sexually transmitted infections; however, the upper reproductive tract may also be a portal of entry and dissemination for pathogens, including HIV-1. METHOD OF STUDY: Endometrial biopsy, endocervical curettage, cytobrush, and blood were collected during mid-luteal phase from 23 healthy women. T-cells were isolated and analyzed by flow cytometry. RESULTS: As compared with their counterparts in blood, endometrial and endocervical T-cells had enhanced CCR5 expression, and were enriched for activated, effector memory cells. Endometrial T-cells were more responsive to polyclonal stimuli, producing a broad range of cytokines and chemokines. CONCLUSION: These findings underscore the responsiveness of endometrial T-cells to stimulation, and reveal their activated phenotype. These findings also suggest susceptibility of the upper reproductive tract to HIV-1 infection.


Asunto(s)
Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD8-positivos/inmunología , Cuello del Útero/inmunología , Endometrio/inmunología , Subgrupos de Linfocitos T/inmunología , Adulto , Separación Celular , Células Cultivadas , Citocinas/metabolismo , Femenino , Citometría de Flujo , Humanos , Memoria Inmunológica , Inmunofenotipificación , Activación de Linfocitos , Premenopausia , Receptores CCR5/metabolismo , Salud de la Mujer
19.
AIDS Res Hum Retroviruses ; 26(8): 895-9, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20672974

RESUMEN

Mutations in the env gene of HIV-1 have been the primary focus in most epidemiologically related cohort studies of virus evolution and very limited studies have focused on the reverse transcriptase (RT) region, the primary target of antiretroviral therapy (ART). Hence, we measured the selection pressure and searched for the positively selected sites in the RT sequences amplified from HIV-1-infected heterosexual transmission pairs. Married couples (n = 10) who were ART naive were included in this study. Phylogenetic analysis, the measurement of synonymous and nonsynonymous ratio (dN/dS) and the interpatient nucleotide variation, was done. Phylogenetic analysis demonstrated distinct subclusters of the RT sequences from heterosexual transmission pairs and the median (IQR) nucleotide variation between the epidemiologically related transmission pairs was significantly (p < 0.001) lower [0.01% (0.01-0.02%)] compared to the epidemiologically unrelated transmission pairs [0.04% (0.03-0.04%)]. The ratio of dN/dS was <1 and codons 135, 162, 166, 207, and 211 were positively selected in >50% of the donor and recipient RT sequences. Purifying selection pressure and low nucleotide variation in the RT sequences between epidemiologically related transmission pairs highlight its essential role in HIV-1 replication. The effect of the RT positively selected mutations that persist over time following transmission between individuals needs to be studied to determine the fitness cost of the mutations in vivo, which may possibly represent good targets for inclusion in HIV-1 vaccines.


Asunto(s)
Variación Genética , Infecciones por VIH/virología , Transcriptasa Inversa del VIH/genética , VIH-1/genética , Selección Genética , Adulto , Secuencia de Bases , Estudios de Cohortes , Femenino , Genes env , Infecciones por VIH/transmisión , Humanos , Masculino , Datos de Secuencia Molecular , Filogenia , Adulto Joven
20.
AIDS Res Hum Retroviruses ; 26(10): 1093-6, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20849301

RESUMEN

Variation of the HIV-1 subtype C reverse transcriptase region (RT) resulting in response to the selective pressures of drug therapy remains poorly characterized. Here, we compared the genetic variation resulting in the presence and absence of antiretroviral drug selective pressures on HIV-1 subtype C RT among nontreated and treated patients. The nucleotide variability, nonsynonymous and synonymous ratio, and the positively selected mutations were determined by comparing the RT sequences isolated at two time points among nontreated (baseline and follow-up) and treated patients (baseline and treatment failure). Compared to the nontreated patients, the intrapatient nucleotide variability, the number of nonsynonymous and synonymous substitutions was significantly higher among the treated patients. Among the mutations positively selected, the frequency of D121Y, I135R, and Q207E increased and the frequency of mutation S48T decreased significantly during treatment failure. Further studies are essential to discover the role of these mutations during treatment in HIV-1 subtype C.


Asunto(s)
Transcriptasa Inversa del VIH/genética , VIH-1/genética , Mutación , Inhibidores de la Transcriptasa Inversa/uso terapéutico , Selección Genética , Adulto , Farmacorresistencia Viral Múltiple , Femenino , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/genética , VIH-1/efectos de los fármacos , Humanos , Masculino , ARN Viral
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