scholarly journals Coreceptor Tropism in Human Immunodeficiency Virus Type 1 Subtype D: High Prevalence of CXCR4 Tropism and Heterogeneous Composition of Viral Populations

2007 ◽  
Vol 81 (15) ◽  
pp. 7885-7893 ◽  
Author(s):  
Wei Huang ◽  
Susan H. Eshleman ◽  
Jonathan Toma ◽  
Signe Fransen ◽  
Eric Stawiski ◽  
...  

ABSTRACT In human immunodeficiency virus type 1 (HIV-1) subtype B, CXCR4 coreceptor use ranges from ∼20% in early infection to ∼50% in advanced disease. Coreceptor use by non-subtype B HIV is less well characterized. We studied coreceptor tropism of subtype A and D HIV-1 collected from 68 pregnant, antiretroviral drug-naive Ugandan women (HIVNET 012 trial). None of 33 subtype A or 10 A/D-recombinant viruses used the CXCR4 coreceptor. In contrast, nine (36%) of 25 subtype D viruses used both CXCR4 and CCR5 coreceptors. Clonal analyses of the nine subtype D samples with dual or mixed tropism revealed heterogeneous viral populations comprised of X4-, R5-, and dual-tropic HIV-1 variants. In five of the six samples with dual-tropic strains, V3 loop sequences of dual-tropic clones were identical to those of cocirculating R5-tropic clones, indicating the presence of CXCR4 tropism determinants outside of the V3 loop. These dual-tropic variants with R5-tropic-like V3 loops, which we designated “dual-R,” use CCR5 much more efficiently than CXCR4, in contrast to dual-tropic clones with X4-tropic-like V3 loops (“dual-X”). These observations have implications for pathogenesis and treatment of subtype D-infected individuals, for the association between V3 sequence and coreceptor tropism phenotype, and for understanding potential mechanisms of evolution from exclusive CCR5 use to efficient CXCR4 use by subtype D HIV-1.

2002 ◽  
Vol 76 (21) ◽  
pp. 10674-10684 ◽  
Author(s):  
Shan-Lu Liu ◽  
John E. Mittler ◽  
David C. Nickle ◽  
Thera M. Mulvania ◽  
Daniel Shriner ◽  
...  

ABSTRACT Although human immunodeficiency virus type 1 (HIV-1) recombinants have been found with high frequency, little is known about the forces that select for these viruses or their importance to pathogenesis. Here we document the emergence and dynamics of 11 distinct HIV-1 recombinants in a man who was infected with two subtype B HIV-1 strains and progressed rapidly to AIDS without developing substantial cellular or humoral immune responses. Although numerous frequency oscillations were observed, a single recombinant lineage eventually came to dominate the population. Numerical simulations indicate that the successive recombinant forms displaced each other too rapidly to be explained by any simple model of random genetic drift or sampling variation. All of the recombinants, including several resulting from independent recombination events, possessed the same sequence motif in the V3 loop, suggesting intense selection on this segment of the viral envelope protein. The outgrowth of the predominant V3 loop recombinants was not, however, associated with changes in coreceptor utilization. The final variant was instead notable for having lost 3 of 14 potential glycosylation sites. We also observed high ratios of synonymous-to-nonsynonymous nucleotide changes—suggestive of purifying selection—in all viral populations, with particularly high ratios in newly arising recombinants. Our study, therefore, illustrates the unusual and important patterns of viral adaptation that can occur in a patient with weak immune responses. Although it is hard to tease apart cause and effect in a single patient, the correlation with disease progression in this patient suggests that recombination between divergent viruses, with its ability to create chimeras with increased fitness, can accelerate progression to AIDS.


1999 ◽  
Vol 37 (3) ◽  
pp. 804-806 ◽  
Author(s):  
P. Chanbancherd ◽  
A. E. Brown ◽  
R. Trichavaroj ◽  
P. Tienamporn ◽  
P. Puthakird ◽  
...  

Dried blood spot (DBS) specimens were assessed as an alternative to plasma for human immunodeficiency virus type 1 (HIV-1) serotyping by V3 loop peptide enzyme immunoassay. Nested PCR capable of distinguishing HIV-1 subtypes B and E was used as the reference standard. Ninety-two percent of DBS samples were typeable as either HIV-1 subtype B or E. Serotype results with DBS and plasma were identical for 254 of 257 specimens. A simple DBS collection method provides a convenient alternative for conducting HIV-1 serotype surveillance while retaining sensitivity and specificity.


2005 ◽  
Vol 79 (10) ◽  
pp. 6528-6531 ◽  
Author(s):  
Bhavna Chohan ◽  
Dorothy Lang ◽  
Manish Sagar ◽  
Bette Korber ◽  
Ludo Lavreys ◽  
...  

ABSTRACT Designing an effective human immunodeficiency virus type 1 (HIV-1) vaccine will rely on understanding which variants, from among the myriad of circulating HIV-1 strains, are most commonly transmitted and determining whether such variants have an Achilles heel. Here we show that heterosexually acquired subtype A HIV-1 envelopes have signature sequences that include shorter V1-V2 loop sequences and fewer predicted N-linked glycosylation sites relative to the overall population of circulating variants. In contrast, recently transmitted subtype B variants did not, and this was true for cases where the major risk factor was homosexual contact, as well as for cases where it was heterosexual contact. This suggests that selection during HIV-1 transmission may vary depending on the infecting subtype. There was evidence from 23 subtype A-infected women for whom there was longitudinal data that those who were infected with viruses with fewer potential N-linked glycosylation sites in V1-V2 had lower viral set point levels. Thus, our study also suggests that the extent of glycosylation in the infecting virus could impact disease progression.


2007 ◽  
Vol 82 (2) ◽  
pp. 664-673 ◽  
Author(s):  
Katrina M. Nolan ◽  
Andrea P. O. Jordan ◽  
James A. Hoxie

ABSTRACT The human immunodeficiency virus type 1 (HIV-1) V3 loop is critical for coreceptor binding and principally determines tropism for the CCR5 and CXCR4 coreceptors. The recent crystallographic resolution of V3 shows that its base is closely associated with the conserved coreceptor binding site on the gp120 core, whereas more distal regions protrude toward the cell surface, likely mediating interactions with coreceptor extracellular loops. However, these V3-coreceptor interactions and the structural basis for CCR5 or CXCR4 specificity are poorly understood. Using the dual-tropic virus HIV-1R3A, which uses both CCR5 and CXCR4, we sought to identify subdomains within V3 that selectively mediate R5 or X4 tropism. An extensive panel of V3 mutants was evaluated for effects on tropism and sensitivity to coreceptor antagonists. Mutations on either side of the V3 base (residues 3 to 8 and 26 to 33) ablated R5 tropism and made the resulting X4-tropic Envs more sensitive to the CXCR4 inhibitor AMD3100. When mutations were introduced within the V3 stem, only a deletion of residues 9 to 12 on the N-terminal side ablated X4 tropism. Remarkably, this R5-tropic Δ9-12 mutant was completely resistant to several small-molecule inhibitors of CCR5. Envs with mutations in the V3 crown (residues 13 to 20) remained dual tropic. Similar observations were made for a second dual-tropic isolate, HIV-189.6. These findings suggest that V3 subdomains can be identified that differentially affect R5 and X4 tropism and modulate sensitivity to CCR5 and CXCR4 inhibitors. These studies provide a novel approach for probing V3-coreceptor interactions and mechanisms by which these interactions can be inhibited.


2009 ◽  
Vol 83 (11) ◽  
pp. 5592-5605 ◽  
Author(s):  
Awet Abraha ◽  
Immaculate L. Nankya ◽  
Richard Gibson ◽  
Korey Demers ◽  
Denis M. Tebit ◽  
...  

ABSTRACT Human immunodeficiency virus type 1 (HIV-1) subtype C is the dominant subtype globally, due largely to the incidence of subtype C infections in sub-Saharan Africa and east Asia. We compared the relative replicative fitness (ex vivo) of the major (M) group of HIV-1 subtypes A, B, C, D, and CRF01_AE and group O isolates. To estimate pathogenic fitness, pairwise competitions were performed between CCR5-tropic (R5) or CXCR4-tropic (X4) virus isolates in peripheral blood mononuclear cells (PBMC). A general fitness order was observed among 33 HIV-1 isolates; subtype B and D HIV-1 isolates were slightly more fit than the subtype A and dramatically more fit than the 12 subtype C isolates. All group M isolates were more fit (ex vivo) than the group O isolates. To estimate ex vivo transmission fitness, a subset of primary HIV-1 isolates were examined in primary human explants from penile, cervical, and rectal tissues. Only R5 isolates and no X4 HIV-1 isolates could replicate in these tissues, whereas the spread to PM1 cells was dependent on active replication and passive virus transfer. In tissue competition experiments, subtype C isolates could compete with and, in some cases, even win over subtype A and D isolates. However, when the migratory cells from infected tissues were mixed with a susceptible cell line, the subtype C isolates were outcompeted by other subtypes, as observed in experiments with PBMC. These findings suggest that subtype C HIV-1 isolates might have equal transmission fitness but reduced pathogenic fitness relative to other group M HIV-1 isolates.


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.


2004 ◽  
Vol 48 (8) ◽  
pp. 2993-2998 ◽  
Author(s):  
Dan Turner ◽  
Bluma Brenner ◽  
Daniela Moisi ◽  
Mervi Detorio ◽  
Raymond Cesaire ◽  
...  

ABSTRACT We have compared nucleotide substitutions and polymorphisms at codons known to confer drug resistance in subtype B strains of human immunodeficiency virus type 1 (HIV-1) with similar substitutions in viruses of other subtypes. Genotypic analysis was performed on viruses from untreated individuals. Nucleotide and amino acid diversity at resistance sites was compared with a consensus subtype B reference virus. Among patients with non-subtype B infections, polymorphisms relative to subtype B were observed at codon 10 in protease (PR). These included silent substitutions (CTC→CTT, CTA, TTA) and an amino acid mutation, L10I. Subtype A viruses possessed a V179I substitution in reverse transcriptase (RT). Subtype G viruses were identified by silent substitutions at codon 181 in RT (TAT→TAC). Similarly, subtype A/G viruses were identified by a substitution at position 67 in RT (GAC→GAT). Subtype C was distinguished by silent substitutions at codons 106 (GTA→GTG) and 219 (AAA→AAG) in RT and codon 48 (GGG→GGA) in PR. Variations relative to subtype B were seen at RT position 215 (ACC→ACT) for subtypes A and A/E. These substitutions and polymorphisms reflect different patterns of codon usage among viruses of different subtypes. However, the existence of different subtypes may only rarely affect patterns of drug resistance-associated mutations.


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.


Sign in / Sign up

Export Citation Format

Share Document