scholarly journals Reconstructing the Dissemination Dynamics of the Major HIV-1 Subtype B Non-Pandemic Lineage Circulating in Brazil

Viruses ◽  
2019 ◽  
Vol 11 (10) ◽  
pp. 909
Author(s):  
Ighor Arantes ◽  
Myuki Alfaia Esashika Crispim ◽  
Mônica Nogueira da Guarda Reis ◽  
Mariane Martins Araújo Stefani ◽  
Gonzalo Bello

Non-pandemic variants of the Human Immunodeficiency Virus Type 1 (HIV-1) subtype B accounts for a significant fraction of HIV infections in several Caribbean islands, Northeastern South American countries and the Northern Brazilian states of Roraima and Amazonas. In this paper, we used a comprehensive dataset of HIV-1 subtype B pol sequences sampled in Amazonas and Roraima between 2007 and 2017 to reconstruct the phylogeographic and demographic dynamics of the major HIV-1 subtype B non-pandemic Brazilian lineage, designated as BCAR-BR-I. Our analyses revealed that its origin could be traced to one of many viral introductions from French Guiana and Guyana into Northern Brazil, which probably occurred in the state of Amazonas around the late 1970s. The BCAR-BR-I clade was rapidly disseminated from Amazonas to Roraima, and the epidemic grew exponentially in these Northern Brazilian states during the 1980s and 1990s, coinciding with a period of economic and fast population growth in the region. The spreading rate of the BCAR-BR-I clade, however, seems to have slowed down since the early 2000s, despite the continued expansion of the HIV-1 epidemic in this region in the last decade.

1999 ◽  
Vol 37 (1) ◽  
pp. 110-116 ◽  
Author(s):  
K. Triques ◽  
J. Coste ◽  
J. L. Perret ◽  
C. Segarra ◽  
E. Mpoudi ◽  
...  

Three versions of a commercial human immunodeficiency virus (HIV) type 1 (HIV-1) load test (the AMPLICOR HIV-1 MONITOR Test versions 1.0, 1.0+, and 1.5; Roche Diagnostics, Branchburg, N.J.) were evaluated for their ability to detect and quantify HIV-1 RNA of different genetic subtypes. Plasma samples from 96 patients infected with various subtypes of HIV-1 (55 patients infected with subtype A, 9 with subtype B, 21 with subtype C, 2 with subtype D, 7 with subtype E, and 2 with subtype G) and cultured virus from 29 HIV-1 reference strains (3 of subtype A, 6 of subtype B, 5 of subtype C, 3 of subtype D, 8 of subtype E, 3 of subtype F, and 1 of subtype G) were tested. Detection of subtypes A and E was significantly improved with versions 1.0+ and 1.5 compared to that with version 1.0, whereas detection of subtypes B, C, D, and G was equivalent with the three versions. Versions 1.0, 1.0+, and 1.5 detected 65, 98, and 100% of the subtype A-infected samples from patients, respectively, and 71, 100, and 100% of the subtype E-infected samples from patients, respectively. Version 1.5 yielded a significant increase in viral load for samples infected with subtypes A and E (greater than 1 log10 HIV RNA copies/ml). For samples infected with subtype B, C, and D and tested with version 1.5, only a slight increase in viral load was observed (<0.5 log10). We also evaluated a prototype automated version of the test that uses the same PCR primers as version 1.5. The results with the prototype automated test were highly correlated with those of the version 1.5 test for all subtypes, but were lower overall. The AMPLICOR HIV-1 MONITOR Test, version 1.5, yielded accurate measurement of the HIV load for all HIV-1 subtypes tested, which should allow the test to be used to assess disease prognosis and response to antiretroviral treatment in patients infected with a group M HIV-1 subtype.


1998 ◽  
Vol 72 (11) ◽  
pp. 9337-9344 ◽  
Author(s):  
Yi-jun Zhang ◽  
Tatjana Dragic ◽  
Yunzhen Cao ◽  
Leondios Kostrikis ◽  
Douglas S. Kwon ◽  
...  

ABSTRACT We have tested a panel of pediatric and adult human immunodeficiency virus type 1 (HIV-1) primary isolates for the ability to employ the following proteins as coreceptors during viral entry: CCR1, CCR2b, CCR3, CCR4, CCR5, CCR8, CXCR4, Bonzo, BOB, GPR1, V28, US28, and APJ. Most non-syncytium-inducing isolates could utilize only CCR5. All syncytium-inducing viruses used CXCR4, some also employed V28, and one (DH123) used CCR8 and APJ as well. A longitudinal series of HIV-1 subtype B isolates from an infected infant and its mother utilized Bonzo efficiently, as well as CCR5. The maternal isolates, which were syncytium inducing, also used CXCR4, CCR8, V28, and APJ.


2007 ◽  
Vol 82 (2) ◽  
pp. 638-651 ◽  
Author(s):  
Yun Li ◽  
Bradley Cleveland ◽  
Igor Klots ◽  
Bruce Travis ◽  
Barbra A. Richardson ◽  
...  

ABSTRACT Glycans on human immunodeficiency virus (HIV) envelope protein play an important role in infection and evasion from host immune responses. To examine the role of specific glycans, we introduced single or multiple mutations into potential N-linked glycosylation sites in hypervariable regions (V1 to V3) of the env gene of HIV type 1 (HIV-1) 89.6. Three mutants tested showed enhanced sensitivity to soluble CD4. Mutant N7 (N197Q) in the carboxy-terminal stem of the V2 loop showed the most pronounced increase in sensitivity to broadly neutralizing antibodies (NtAbs), including those targeting the CD4-binding site (IgG1b12) and the V3 loop (447-52D). This mutant is also sensitive to CD4-induced NtAb 17b in the absence of CD4. Unlike the wild-type (WT) Env, mutant N7 mediates CD4-independent infection in U87-CXCR4 cells. To study the immunogenicity of mutant Env, we immunized pig-tailed macaques with recombinant vaccinia viruses, one expressing SIVmac239 Gag-Pol and the other expressing HIV-1 89.6 Env gp160 in WT or mutant forms. Animals were boosted 14 to 16 months later with simian immunodeficiency virus gag DNA and the cognate gp140 protein before intrarectal challenge with SHIV89.6P-MN. Day-of-challenge sera from animals immunized with mutant N7 Env had significantly higher and broader neutralizing activities than sera from WT Env-immunized animals. Neutralizing activity was observed against SHIV89.6, SHIV89.6P-MN, HIV-1 SF162, and a panel of subtype B primary isolates. Compared to control animals, immunized animals showed significant reduction of plasma viral load and increased survival after challenge, which correlated with prechallenge NtAb titers. These results indicate the potential advantages for glycan modification in vaccine design, although the role of specific glycans requires further examination.


2004 ◽  
Vol 78 (13) ◽  
pp. 7279-7283 ◽  
Author(s):  
Manish Sagar ◽  
Erin Kirkegaard ◽  
E. Michelle Long ◽  
Connie Celum ◽  
Susan Buchbinder ◽  
...  

ABSTRACT African women frequently acquire several genetically distinct human immunodeficiency virus type 1 (HIV-1) variants from a heterosexual partner, whereas the acquisition of multiple variants appears to be rare in men. To determine whether newly infected individuals in other risk groups acquire genetically diverse viruses, we examined the viral envelope sequences in plasma samples from 13 women and 4 men from the United States infected with subtype B viruses and 10 men from Kenya infected with non-subtype B viruses. HIV-1 envelope sequences differed by more than 2% in three U.S. women, one U.S. man, and one Kenyan man near the time of seroconversion. These findings suggest that early HIV-1 genetic diversity is not exclusive to women from Africa or to infection with any particular HIV-1 subtype.


2009 ◽  
Vol 83 (19) ◽  
pp. 10269-10274 ◽  
Author(s):  
Anne Piantadosi ◽  
Dana Panteleeff ◽  
Catherine A. Blish ◽  
Jared M. Baeten ◽  
Walter Jaoko ◽  
...  

ABSTRACT The determinants of a broad neutralizing antibody (NAb) response and its effect on human immunodeficiency virus type 1 (HIV-1) disease progression are not well defined, partly because most prior studies of a broad NAb response were cross-sectional. We examined correlates of NAb response breadth among 70 HIV-infected, antiretroviral-naïve Kenyan women from a longitudinal seroincident cohort. NAb response breadth was measured 5 years after infection against five subtype A viruses and one subtype B virus. Greater NAb response breadth was associated with a higher viral load set point and greater HIV-1 env diversity early in infection. However, greater NAb response breadth was not associated with a delayed time to a CD4+ T-cell count of <200, antiretroviral therapy, or death. Thus, a broad NAb response results from a high level of antigenic stimulation early in infection, which likely accounts for prior observations that greater NAb response breadth is associated with a higher viral load later in infection.


2010 ◽  
Vol 84 (15) ◽  
pp. 7651-7661 ◽  
Author(s):  
Andrea Galli ◽  
Mary Kearney ◽  
Olga A. Nikolaitchik ◽  
Sloane Yu ◽  
Mario P. S. Chin ◽  
...  

ABSTRACT High-frequency recombination is a hallmark of HIV-1 replication. Recombination can occur between two members of the same subtype or between viruses from two different subtypes, generating intra- or intersubtype recombinants, respectively. Many intersubtype recombinants have been shown to circulate in human populations. We hypothesize that sequence diversity affects the emergence of viable recombinants by decreasing recombination events and reducing the ability of the recombinants to replicate. To test our hypothesis, we compared recombination between two viruses containing subtype B pol genes (B/B) and between viruses with pol genes from subtype B or F (B/F). Recombination events generated during a single cycle of infection without selection pressure on pol gene function were analyzed by single-genome sequencing. We found that recombination occurred slightly (∼30%) less frequently in B/F than in B/B viruses, and the overall distribution of crossover junctions in pol was similar for the two classes of recombinants. We then examined the emergence of recombinants in a multiple cycle assay, so that functional pol gene products were selected. We found that the emerging B/B recombinants had complex patterns, and the crossover junctions were distributed throughout the pol gene. In contrast, selected B/F recombinants had limited recombination patterns and restricted crossover junction distribution. These results provide evidence for the evolved coadapted sites in variants from different subtypes; these sites may be segregated by recombination events, causing the newly generated intersubtype recombinants to undergo purifying selection. Therefore, the ability of the recombinants to replicate is the major barrier for many of these viruses.


2012 ◽  
Vol 93 (12) ◽  
pp. 2625-2634 ◽  
Author(s):  
Elena Capel ◽  
Glòria Martrus ◽  
Mariona Parera ◽  
Bonaventura Clotet ◽  
Miguel Angel Martínez

The rapid spread of human immunodeficiency virus type 1 (HIV-1) in humans has been accompanied by continuous extensive genetic diversification of the virus. The aim of this study was to investigate the impact of HIV-1 diversification on HIV-1 replication capacity (RC) and mutational robustness. Thirty-three HIV-1 protease sequences were amplified from three groups of viruses: two naïve sample groups isolated 15 years apart plus a third group of protease inhibitor-(PI) resistant samples. The amplified proteases were recombined with an HXB2 infectious clone and RC was determined in MT-4 cells. RC was also measured in these three groups after random mutagenesis in vitro using error-prone PCR. No significant RC differences were observed between recombinant viruses from either early or recent naïve isolates (P = 0.5729), even though the proteases from the recent isolates had significantly lower sequence conservation scores compared with a subtype B ancestral sequence (P<0.0001). Randomly mutated recombinant viruses from the three groups exhibited significantly lower RC values than the corresponding wild-type viruses (P<0.0001). There was no significant difference regarding viral infectivity reduction between viruses carrying randomly mutated naïve proteases from early or recent sample isolates (P = 0.8035). Interestingly, a significantly greater loss of RC was observed in the PI-resistant protease group (P = 0.0400). These results demonstrate that protease sequence diversification has not affected HIV-1 RC or protease robustness and indicate that proteases carrying PI resistance substitutions are less robust than naïve proteases.


2008 ◽  
Vol 82 (23) ◽  
pp. 11651-11668 ◽  
Author(s):  
James M. Binley ◽  
Elizabeth A. Lybarger ◽  
Emma T. Crooks ◽  
Michael S. Seaman ◽  
Elin Gray ◽  
...  

ABSTRACT Identifying the viral epitopes targeted by broad neutralizing antibodies (NAbs) that sometimes develop in human immunodeficiency virus type 1 (HIV-1)-infected subjects should assist in the design of vaccines to elicit similar responses. Here, we investigated the activities of a panel of 24 broadly neutralizing plasmas from subtype B- and C-infected donors using a series of complementary mapping methods, focusing mostly on JR-FL as a prototype subtype B primary isolate. Adsorption with gp120 immobilized on beads revealed that an often large but variable fraction of plasma neutralization was directed to gp120 and that in some cases, neutralization was largely mediated by CD4 binding site (CD4bs) Abs. The results of a native polyacrylamide gel electrophoresis assay using JR-FL trimers further suggested that half of the subtype B and a smaller fraction of subtype C plasmas contained a significant proportion of NAbs directed to the CD4bs. Anti-gp41 neutralizing activity was detected in several plasmas of both subtypes, but in all but one case, constituted only a minor fraction of the overall neutralization activity. Assessment of the activities of the subtype B plasmas against chimeric HIV-2 viruses bearing various fragments of the membrane proximal external region (MPER) of HIV-1 gp41 revealed mixed patterns, implying that MPER neutralization was not dominated by any single specificity akin to known MPER-specific monoclonal Abs. V3 and 2G12-like NAbs appeared to make little or no contribution to JR-FL neutralization titers. Overall, we observed significant titers of anti-CD4bs NAbs in several plasmas, but approximately two-thirds of the neutralizing activity remained undefined, suggesting the existence of NAbs with specificities unlike any characterized to date.


2006 ◽  
Vol 80 (3) ◽  
pp. 1311-1320 ◽  
Author(s):  
Eduardo O'Neill ◽  
Lillian S. Kuo ◽  
John F. Krisko ◽  
Diana R. Tomchick ◽  
J. Victor Garcia ◽  
...  

ABSTRACT The human immunodeficiency virus type 1 (HIV-1) early gene product Nef is a multifunctional protein that alters numerous pathways of T-cell function, including endocytosis, signal transduction, vesicular trafficking, and immune modulation, and is a major determinant of pathogenesis. Individual Nef functions include PAK-2 activation, CD4 downregulation, major histocompatibility complex (MHC) class I downregulation, and enhancement of viral particle infectivity. How Nef accomplishes its multiple tasks presents a difficult problem of mechanistic analysis because of the complications associated with multiple, overlapping functional domains in the context of significant sequence variability. To address these issues we determined the conservation of each Nef residue based on 1,643 subtype B Nef sequences. Mutational analysis based on conservative substitutions and Nef sequence data allowed us to search for amino acids on the surface of Nef that are specifically required for PAK-2 activation. We found residues 85, 89, and 191 to be highly significant determinants for Nef's PAK-2 activation function but functionally unlinked to CD4 and MHC class I downregulation or enhancement of infectivity. These residues are not conserved across HIV-1 subtypes but are confined to separate sets of surface elements within a subtype. Thus, L85/H89/F191 and F85/F89/R191 are dominant in subtype B and subtype E or C, respectively. Our results provide support for developing subtype-specific interventions in HIV-1 disease.


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