scholarly journals Transmission of HIV-1 Gag immune escape mutations is associated with reduced viral load in linked recipients

2008 ◽  
Vol 205 (5) ◽  
pp. 1009-1017 ◽  
Author(s):  
Paul A. Goepfert ◽  
Wendy Lumm ◽  
Paul Farmer ◽  
Philippa Matthews ◽  
Andrew Prendergast ◽  
...  
Keyword(s):  
Viral Load ◽  
Immune Escape ◽  
Cytotoxic T Lymphocyte ◽  
Human Leukocyte ◽  
Viral Fitness ◽  
Leukocyte Antigen ◽  
Ctl Escape ◽  
The Impact ◽  
Hiv 1

In a study of 114 epidemiologically linked Zambian transmission pairs, we evaluated the impact of human leukocyte antigen class I (HLA-I)–associated amino acid polymorphisms, presumed to reflect cytotoxic T lymphocyte (CTL) escape in Gag and Nef of the virus transmitted from the chronically infected donor, on the plasma viral load (VL) in matched recipients 6 mo after infection. CTL escape mutations in Gag and Nef were seen in the donors, which were subsequently transmitted to recipients, largely unchanged soon after infection. We observed a significant correlation between the number of Gag escape mutations targeted by specific HLA-B allele–restricted CTLs and reduced VLs in the recipients. This negative correlation was most evident in newly infected individuals, whose HLA alleles were unable to effectively target Gag and select for CTL escape mutations in this gene. Nef mutations in the donor had no impact on VL in the recipient. Thus, broad Gag-specific CTL responses capable of driving virus escape in the donor may be of clinical benefit to both the donor and recipient. In addition to their direct implications for HIV-1 vaccine design, these data suggest that CTL-induced viral polymorphisms and their associated in vivo viral fitness costs could have a significant impact on HIV-1 pathogenesis.

scholarly journals Global Database-Driven Assessment of HIV-1 Adaptation to the Immune Repertoires of Human Populations

2015 ◽  
Vol 89 (20) ◽  
pp. 10693-10695 ◽  
Author(s):  
Aram Karakas ◽  
Zabrina L. Brumme ◽  
Art F. Y. Poon
Keyword(s):  
T Lymphocyte ◽  
Cytotoxic T Lymphocyte ◽  
Human Leukocyte ◽  
Human Populations ◽  
Hla Alleles ◽  
Global Database ◽  
Leukocyte Antigen ◽  
Ctl Escape ◽  
The Relationship ◽  
Hiv 1

Associations between HIV-1 cytotoxic T lymphocyte (CTL) escape mutations and their restricting human leukocyte antigen (HLA) alleles imply that HIV could adapt to divergent HLA repertoires of human populations globally. Using publicly available databases, we examine the relationship between the frequencies of 19 experimentally validated CTL escape mutations in HIV-1 reverse transcriptase and their restricting HLA alleles in 59 countries. From these extensive data, we find evidence of differential HIV adaptations to human populations at only a limited number of the studied epitope sites.

Characteristics allelic of Human Leukocyte Antigen class I genotype and association with viral load and CD4 cell count in HIV-1 infected patients, Hanoi 2014 – 2016

2021 ◽  
Vol 31 (4) ◽  
pp. 43-50
Author(s):  
Tran Thi Minh Tam ◽  
Nguyen Thuy Linh ◽  
Phan Ha My ◽  
Nguyen Thi Lan Anh
Keyword(s):  
Viral Load ◽  
Human Leukocyte ◽  
Hla Class I ◽  
Class I ◽  
Cd4 Cell Count ◽  
Leukocyte Antigen ◽  
Cell Counts ◽  
Cd4 Cell Counts ◽  
Cd4 Cell ◽  
Hiv 1

Human Leukocyte Antigen (HLA) class I plays a regulatory role in cellular immune response to HIV-1 infection. The role of HLA alleles in HIV progression via viral load and CD4 cell count is well known. HLA class I is polymorphic and distributed differently by nation. This descriptive cross-sectional study was performed on 303 HIV-1 infected patients in 2014 - 2016, with aims to (i) characterize HLA class I genotype with 4-digit nomenclature and (ii) identify specifc alleles in correlate with CD4 cell counts and HIV viral load. 117 allele genotypes have been identifed, including 28 HLA-A alleles, 54 HLA-B alleles and 35 HLA-C alleles. The results showed that the most prevalent alleles in the population include A*11:01 (30.7%), B*15:02 (15.2%) and C*08:01 (17.1%). The frequency of haplotype created from these alleles is 8.4%. A*02:03, B*46:01 related to gender and ethnicity respectively. In conclusion, the study provided detailed pattern of HLA class I expression in a study population of HIV-1 infected patients and reported for the frst time the associated B*51:01, C*14:02 alleles associated to an increase in CD4 cell counts.

Human leukocyte antigen-specific polymorphisms in HIV-1 Gag and their association with viral load in chronic untreated infection

AIDS ◽  
2008 ◽  
Vol 22 (11) ◽  
pp. 1277-1286 ◽  
Author(s):  
Zabrina L Brumme ◽  
Iris Tao ◽  
Sharon Szeto ◽  
Chanson J Brumme ◽  
Jonathan M Carlson ◽  
...  
Keyword(s):  
Viral Load ◽  
Human Leukocyte Antigen ◽  
Human Leukocyte ◽  
Leukocyte Antigen ◽  
Hiv 1

scholarly journals Immune escape mutations selected by neutralizing antibodies in natural HIV-1 infection can alter coreceptor usage repertoire of the transmitted/founder virus

2021 ◽  
Author(s):  
Manukumar Honnayakanahalli Marichannegowda ◽  
Hongshuo Song
Keyword(s):  
Neutralizing Antibodies ◽  
Immune Escape ◽  
Escape Mutation ◽  
Coreceptor Usage ◽  
Founder Virus ◽  
The Impact ◽  
Glycan Site ◽  
Hiv 1 ◽  
Transmitted Founder Virus

The ability of HIV-1 to evade neutralizing antibodies (NAbs) in vivo is well demonstrated, but the impact of NAb escape mutations on HIV-1 phenotype other than immune escape itself has rarely been studied. Here, we show that immune escape mutations selected by V3-glycan specific NAbs in vivo can alter the coreceptor usage repertoire of the transmitted/founder (T/F) HIV-1. In a participant developed V3-glycan NAb response, naturally selected mutations at the V3 N301 and N332 glycan sites abrogated CCR8 usage while conferred APJ usage on the cognate T/F strain. Mutations at the N301 glycan also impaired CCR3 usage and partially compromised the efficiency in using CCR5, which could be fully restored by a single escape mutation at the N332 glycan site. Our study demonstrates the link between NAb escape and coreceptor usage alteration in natural HIV-1 infection and indicates that NAb response could drive virus entry tropism evolution in vivo.

scholarly journals Reduced Viral Replication Capacity of Human Immunodeficiency Virus Type 1 Subtype C Caused by Cytotoxic-T-Lymphocyte Escape Mutations in HLA-B57 Epitopes of Capsid Protein

2008 ◽  
Vol 83 (6) ◽  
pp. 2460-2468 ◽  
Author(s):  
Christian L. Boutwell ◽  
Christopher F. Rowley ◽  
M. Essex
Keyword(s):  
T Lymphocyte ◽  
Cytotoxic T Lymphocyte ◽  
Resistance Mutation ◽  
Relative Fitness ◽  
Replication Capacity ◽  
Subtype C ◽  
Triple Mutant ◽  
Ctl Escape ◽  
The Impact

ABSTRACT Cytotoxic-T-lymphocyte (CTL) escape mutations in human immunodeficiency viruses encode amino acid substitutions in positions that disrupt CTL targeting, thereby increasing virus survival and conferring a relative fitness benefit. However, it is now clear that CTL escape mutations can also confer a fitness cost, and there is increasing evidence to suggest that in some cases, e.g., escape from HLA-B*57/B*5801-restricted responses, the costs to the escape virus may affect the clinical course of infection. To quantify the magnitude of the costs of HLA-B*57/B*5801 escape, a highly sensitive dual-infection assay that uses synonymous nucleotide sequence tags to quantify viral relative replication capacity (RRC) was developed. We then asked whether such CTL escape mutations had an impact equivalent to that seen for a benchmark mutation, the M184V antiretroviral drug resistance mutation of reverse transcriptase (RRCV184 = 0.86). To answer the question, the RRCs were quantified for escape mutations in three immunodominant HLA-B*57/B*5801 epitopes in capsid: A146P in IW9 (RRCP146 = 0.91), A163G in KF11 (RRCG163 = 0.89), and T242N in TW10 (RRCN242 = 0.86). Individually, the impact of the escape mutations on RRC was comparable to that of M184V, while coexpression of the mutations resulted in substantial further reductions, with the maximum impact observed for the triple mutant (RRCP146-G163-N242 = 0.62). By comparison to M184V, the magnitude of the reductions in RRC caused by the escape mutations, particularly when coexpressed, suggests that the costs of escape are sufficient to affect in vivo viral dynamics and may thus play a role in the protective effect associated with HLA-B*57/B*5801.

scholarly journals Impaired ability of Nef to counteract SERINC5 is associated with reduced plasma viremia in HIV-infected individuals

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Mako Toyoda ◽  
Doreen Kamori ◽  
Toong Seng Tan ◽  
Kageaki Goebuchi ◽  
Jun Ohashi ◽  
...  
Keyword(s):  
Viral Load ◽  
Plasma Viral Load ◽  
Immune Escape ◽  
Hla Class I ◽  
Viral Fitness ◽  
Single Mutation ◽  
Host Restriction ◽  
Selective Forces ◽  
Differential Ability

Abstract HIV-1 Nef plays an essential role in enhancing virion infectivity by antagonizing the host restriction molecule SERINC5. Because Nef is highly polymorphic due to the selective forces of host cellular immunity, we hypothesized that certain immune-escape polymorphisms may impair Nef’s ability to antagonize SERINC5 and thereby influence viral fitness in vivo. To test this hypothesis, we identified 58 Nef polymorphisms that were overrepresented in HIV-infected patients in Japan sharing the same HLA genotypes. The number of immune-associated Nef polymorphisms was inversely correlated with the plasma viral load. By breaking down the specific HLA allele-associated mutations, we found that a number of the HLA-B*51:01-associated Y120F and Q125H mutations were most significantly associated with a reduced plasma viral load. A series of biochemical experiments showed that the double mutations Y120F/Q125H, but not either single mutation, impaired Nef’s ability to antagonize SERINC5 and was associated with decreasing virion infectivity and viral replication in primary lymphocytes. In contrast, other Nef functions such as CD4, CCR5, CXCR4 and HLA class I downregulation and CD74 upregulation remained unchanged. Taken together, our results suggest that the differential ability of Nef to counteract SERINC5 by naturally occurring immune-associated mutations was associated with the plasma viral load in vivo.

scholarly journals Identification of an HLA-A*0201-restricted cytotoxic T-lymphocyte epitope in rotavirus VP6 protein

2006 ◽  
Vol 87 (11) ◽  
pp. 3393-3396 ◽  
Author(s):  
Jing Wei ◽  
Jin-Tao Li ◽  
Xiao-Ping Zhang ◽  
Yan Tang ◽  
Jing-Xue Wang ◽  
...  
Keyword(s):  
Cytotoxic T Lymphocyte ◽  
Human Leukocyte ◽  
Hla Class I ◽  
Peripheral Blood Lymphocytes ◽  
T Cell Epitopes ◽  
Computer Algorithms ◽  
Leukocyte Antigen ◽  
Healthy Donors

The function of cytotoxic T lymphocytes (CTLs) in rotavirus (RV) infection in humans is poorly understood. To date, no RV-specific human leukocyte antigen (HLA) class I-restricted T-cell epitopes have been described. In this study, four peptides derived from human RV Wa strain VP6 protein were predicted by computer algorithms and verified by an HLA*0201-binding assay. Two peptides with high affinity for HLA-A*0201 molecules were further assessed. The CTLs induced in vitro by P340–348 (TLLANVTAV)-loaded autologous dendritic cells from peripheral blood lymphocytes of HLA-A*0201-matched healthy donors released gamma interferon specifically upon stimulation with P340–348-loaded T2 cells. The CTLs lysed both P340–348-loaded T2 cells and human RV Wa strain-infected HLA-A*0201+ Caco-2 cells in an antigen-specific and HLA-A*0201-restricted manner. At the same time, P340–348 was shown to be immunogenic in vivo in HLA-A*0201/Kb transgenic mice. It is proposed that P340–348 is an HLA-A*0201-restricted CTL epitope.

HIV-1 POPULATION DYNAMICS IN VIVO: IMPLICATIONS FOR PATHOGENESIS, EFFECT OF CYTOKINE AND THERAPY STRATEGY

2004 ◽  
Vol 12 (03) ◽  
pp. 315-333
Author(s):  
JIE LOU ◽  
ZHIEN MA ◽  
MEIZHI LOU ◽  
YIMING SHAO
Keyword(s):  
Immune Response ◽  
T Cells ◽  
Immune System ◽  
Immune Escape ◽  
Interleukin 2 ◽  
Human Immune System ◽  
Therapy Strategy ◽  
The Impact ◽  
Hiv 1

In this paper, we present a dynamical model to study the spread of HIV-1 in vivo. Our goal is to better understand the interaction between HIV-1 and the human immune system. Making use of the Hill function, we describe two kinds of processions occurring in the immune response: the activation interactions or inhibitory interactions occurring between different components in the immune response, and the autocatalytic maintenance of the CD4+ T cells and CD8+ T cells populations. We also consider the impact of the cytokine interleukin-2 (IL-2) and the CD8 antiviral factor (CAF) on HIV-1 infection. Through numerical simulations we get several results. First, we find that the effects of IL-2 and CAF in the treatment for the infected are limiting. Namely, the curative effect will not always increase along with the dose of IL-2 or CAF or both. The increasing trend will stagnate at a certain dose that we used. Second, we find some possible reasons for the collapse of the lymph system in HIV-1 infection — the loss of these restraining functions, and/or the genetic variability of the virus due to immune escape that enhances the virulence, which then bring the collapse of the immune system. In some conditions the system will produce a Hopf bifurcation. We also simulate the theoretical warrant of the feasibility of the combined chemotherapy strategies for the HIV-1 infected patient.

scholarly journals Cytotoxic T-Lymphocyte Escape Mutations Identified by HLA Association Favor Those Which Escape and Revert Rapidly

2012 ◽  
Vol 86 (16) ◽  
pp. 8568-8580 ◽  
Author(s):  
Helen R. Fryer ◽  
John Frater ◽  
Anna Duda ◽  
Duncan Palmer ◽  
Rodney E. Phillips ◽  
...  
Keyword(s):  
T Lymphocyte ◽  
Immune Escape ◽  
Cytotoxic T Lymphocyte ◽  
Population Level ◽  
Escape Mutation ◽  
Cross Sectional ◽  
Hla Association ◽  
Escape Mutants ◽  
Ctl Escape ◽  
The Impact

Identifying human immunodeficiency virus (HIV) immune escape mutations has implications for understanding the impact of host immunity on pathogen evolution and guiding the choice of vaccine antigens. One means of identifying cytotoxic-T-lymphocyte (CTL) escape mutations is to search for statistical associations between mutations and host human leukocyte antigen (HLA) class I alleles at the population level. The impact of evolutionary rates on the strength of such associations is not well defined. Here, we address this topic using a mathematical model of within-host evolution and between-host transmission of CTL escape mutants that predicts the prevalence of escape mutants at the population level. We ask how the rates at which an escape mutation emerges in a host who bears the restricting HLA and reverts when transmitted to a host who does not bear the HLA affect the strength of an association. We consider the impact of these factors when using a standard statistical method to test for an association and when using an adaptation of that method that corrects for phylogenetic relationships. We show that with both methods, the average sample size required to identify an escape mutation is smaller if the mutation escapes and reverts quickly. Thus, escape mutations identified as HLA associated systematically favor those that escape and revert rapidly. We also present expressions that can be used to infer escape and reversion rates from cross-sectional escape prevalence data.

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