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1.
Mem Inst Oswaldo Cruz ; 118: e230066, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37283423

RESUMO

BACKGROUND: Elite controllers (EC) are human immunodeficiency virus (HIV)-positive individuals who can maintain low viral loads for extended periods without antiretroviral therapy due to multifactorial and individual characteristics. Most have a small HIV-1 reservoir composed of identical proviral sequences maintained by clonal expansion of infected CD4+ T cells. However, some have a more diverse peripheral blood mononuclear cell (PBMC)-associated HIV-1 reservoir with unique sequences. OBJECTIVES: To understand the turnover dynamics of the PBMC-associated viral quasispecies in ECs with relatively diverse circulating proviral reservoirs. METHODS: We performed single genome amplification of the env gene at three time points during six years in two EC with high intra-host HIV DNA diversity. FINDINGS: Both EC displayed quite diverse PBMCs-associated viral quasispecies (mean env diversity = 1.9-4.1%) across all time-points comprising both identical proviruses that are probably clonally expanded and unique proviruses with evidence of ongoing evolution. HIV-1 env glycosylation pattern suggests that ancestral and evolving proviruses may display different phenotypes of resistance to broadly neutralising antibodies consistent with persistent immune pressure. Evolving viruses may progressively replace the ancestral ones or may remain as minor variants in the circulating proviral population. MAIN CONCLUSIONS: These findings support that the high intra-host HIV-1 diversity of some EC resulted from long-term persistence of archival proviruses combined with the continuous reservoir's reseeding and low, but measurable, viral evolution despite undetectable viremia.


Assuntos
Infecções por HIV , HIV-1 , Humanos , Provírus/genética , HIV-1/genética , Quase-Espécies/genética , Leucócitos Mononucleares , Carga Viral , Linfócitos T CD4-Positivos
2.
Mem. Inst. Oswaldo Cruz ; 118: e230066, 2023. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1440670

RESUMO

BACKGROUND Elite controllers (EC) are human immunodeficiency virus (HIV)-positive individuals who can maintain low viral loads for extended periods without antiretroviral therapy due to multifactorial and individual characteristics. Most have a small HIV-1 reservoir composed of identical proviral sequences maintained by clonal expansion of infected CD4+ T cells. However, some have a more diverse peripheral blood mononuclear cell (PBMC)-associated HIV-1 reservoir with unique sequences. OBJECTIVES To understand the turnover dynamics of the PBMC-associated viral quasispecies in ECs with relatively diverse circulating proviral reservoirs. METHODS We performed single genome amplification of the env gene at three time points during six years in two EC with high intra-host HIV DNA diversity. FINDINGS Both EC displayed quite diverse PBMCs-associated viral quasispecies (mean env diversity = 1.9-4.1%) across all time-points comprising both identical proviruses that are probably clonally expanded and unique proviruses with evidence of ongoing evolution. HIV-1 env glycosylation pattern suggests that ancestral and evolving proviruses may display different phenotypes of resistance to broadly neutralising antibodies consistent with persistent immune pressure. Evolving viruses may progressively replace the ancestral ones or may remain as minor variants in the circulating proviral population. MAIN CONCLUSIONS These findings support that the high intra-host HIV-1 diversity of some EC resulted from long-term persistence of archival proviruses combined with the continuous reservoir's reseeding and low, but measurable, viral evolution despite undetectable viremia.

3.
Viruses ; 14(12)2022 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-36560806

RESUMO

The analysis of the HIV-1 proviral dynamics after superinfection in the context of both natural and antiretroviral therapy (ART)-mediated suppression could yield unique insights into understanding the persistence of viral variants that seeded the infected cells at different times. In this study, we performed a longitudinal analysis of the env diversity of PBMC-associated HIV DNA quasispecies in two HIV controllers (EEC09 and VC32) that were superinfected with subtype F1 viruses several years after primoinfection with subtype B viruses. Patient EEC09 started ART soon after superinfection, while patient VC32 maintained a natural control of virus replication for at least six years following the superinfection. Our analysis revealed no significant temporal changes in the overall proportion of primo-infecting and superinfecting proviral variants over 2-3 years after superinfection in both HIV controllers. Upon the introduction of ART, individual EEC09 displayed no evidence of HIV-infected cell turnover or viral evolution, while subject VC32 displayed some level of HIV-infected cell reseeding and detectable evolution (divergence) of both viral variants. These results confirm that proviral variants that seeded the reservoir at different times throughout infection could persist for long periods under fully suppressive ART or natural viremic control, but the HIV-1 proviral dynamics could be different in both settings.


Assuntos
Infecções por HIV , Soropositividade para HIV , HIV-1 , Superinfecção , Humanos , Provírus/genética , HIV-1/genética , Leucócitos Mononucleares , Replicação Viral , Carga Viral
4.
Viruses ; 14(8)2022 08 12.
Artigo em Inglês | MEDLINE | ID: mdl-36016383

RESUMO

The human immunodeficiency virus type 1 (HIV-1) can be transmitted via parenteral, sexual, or vertical exposure routes. The number of HIV-1 cases detected yearly in children and adolescents in Brazil did not decrease over the last decade, representing ~5% of total cases described in the country. In recent years, the HIV-1 diversity and the prevalence of transmitted drug resistance mutations (TDRM) are moving toward a marked increase. In this study, we retrospectively evaluated the diversity of HIV-1 subtypes and the TDRM prevalence in 135 treatment-naïve HIV-1 vertically infected children and adolescents born in between 1993 and 2012. These children were assessed in either 2001-2007 or 2008-2012 when they were 0 to 17 years old. The individuals assessed in 2001-2007 (n = 38) had median CD4+ T cell counts of 1218 cells/mm3 (IQR: 738-2.084) and median HIV-1 plasma viral load of 4.18 log10 copies/mL (IQR: 3.88-4.08). The individuals (n = 97) evaluated in 2008-2012 showed median CD4+ T cell counts of 898.5 cells/mm3 (IQR: 591.3-1.821) and median HIV-1 plasma viral load of 4.69 log10 copies/mL (IQR: 4.26-5.33). A steady decrease in the median CD4 T+ cell counts was observed with age progression, as expected. The majority HIV-1 pol sequences (87%) were classified as pure HIV-1 subtypes (77% subtype B, 9% subtype F1 and 1.5% subtype C), while 13% of sequences were classified as recombinants (CRF45_cpx, n = 4; CRF28/29_BF1, n = 2; CRF02_AG, n = 1; CRF40_BF1, n = 1, CRF99_BF1, n = 1, URF_BF1, n = 8). The overall prevalence of TDRM was 14% (19/135), conferring resistance to the nucleoside reverse transcriptase inhibitors (NRTI, 13/135-9.6%), non-nucleoside reverse transcriptase inhibitors (NNRTI, 8/135-5.9%), and protease inhibitors (PI, 2/135-1.5%). The main TDRM observed for NNRTI was the K103N (n = 8), while the mutations T215I/Y/D/E (n = 7) and M184V (n = 4) were the main TDRM for NRTI. Only two TDRM were observed for PI in one individual each (M46I and V82A). Most TDRM were found in the HIV-1 subtype B (84%) sequences. This study reveals an HIV-1 epidemic with high diversity and moderate prevalence of TDRM in the pediatric population of Rio de Janeiro, indicating the existence of possible problems in the clinical management of prophylactic therapy to prevent mother-to-child transmission and future treatment options for the affected children.


Assuntos
Fármacos Anti-HIV , Infecções por HIV , HIV-1 , Adolescente , Fármacos Anti-HIV/farmacologia , Fármacos Anti-HIV/uso terapêutico , Brasil/epidemiologia , Criança , Pré-Escolar , Farmacorresistência Viral/genética , Feminino , Genótipo , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , HIV-1/genética , Humanos , Lactente , Recém-Nascido , Transmissão Vertical de Doenças Infecciosas , Mutação , Estudos Retrospectivos , Inibidores da Transcriptase Reversa/uso terapêutico
5.
BMC Infect Dis ; 19(1): 588, 2019 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-31277590

RESUMO

BACKGROUND: HIV controllers (HICs) are a rare group of HIV-1-infected individuals able to naturally control viral replication. Several studies have identified the occurrence of HIV dual infections in seropositive individuals leading to disease progression. In HICs, however, dual infections with divergent outcomes in pathogenesis have been described. CASE PRESENTATION: Here, we present a case report of a HIC diagnosed in late 1999 who displayed stable CD4+ T cell levels and low plasmatic viral load across 12 years of follow-up. In early 2013, the patient started to present an increase in viral load, reaching a peak of 10,000 copies/ml in early 2014, followed by an oscillation of viremia at moderate levels in the following years. The genetic diversity of env proviral quasispecies from peripheral blood mononuclear cells (PBMCs) was studied by single genome amplification (SGA) at six timepoints across 2009-2017. Phylogenetic analyses of env sequences from 2009 and 2010 samples showed the presence of a single subtype B variant (called B1). Analyses of sequences from 2011 and after revealed an additional subtype B variant (called B2) and a subsequent dominance shift in the proviral quasispecies frequencies, with the B2 variant becoming the most frequent from 2014 onwards. Latent syphilis related to unprotected sexual intercourse was diagnosed a year before the first detection of B2, evidencing risk behavior and supporting the superinfection hypothesis. Immunologic analyses revealed an increase in CD8+ and CD4+ T cell immune activation following viremia increase and minor T cell subset alterations during follow-up. HIV-specific T cell responses remained low throughout the follow-up period. CONCLUSIONS: Altogether, these results show that loss of viremia control in the HIC was associated with superinfection. These data alert to the negative consequences of reinfection on HIV pathogenesis, even in patients with a long history of viremia control and an absence of disease progression, reinforcing the need for continued use of adequate prevention strategies.


Assuntos
Infecções por HIV/virologia , HIV-1/fisiologia , Superinfecção/virologia , Replicação Viral/fisiologia , Adulto , Fármacos Anti-HIV/uso terapêutico , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/virologia , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/virologia , Feminino , Seguimentos , Infecções por HIV/tratamento farmacológico , HIV-1/isolamento & purificação , HIV-1/patogenicidade , Antígenos HLA-B/genética , Humanos , Leucócitos Mononucleares/virologia , Masculino , Filogenia , RNA Viral/sangue , Sífilis/diagnóstico , Carga Viral , Viremia/tratamento farmacológico , Viremia/virologia
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