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1.
Ann Intern Med ; 135(9): 782-95, 2001 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-11694103

RESUMO

BACKGROUND: Studies relating certain chemokine and chemokine receptor gene alleles with the outcome of HIV-1 infection have yielded inconsistent results. OBJECTIVE: To examine postulated associations of genetic alleles with HIV-1 disease progression. DESIGN: Meta-analysis of individual-patient data. SETTING: 19 prospective cohort studies and case-control studies from the United States, Europe, and Australia. PATIENTS: Patients with HIV-1 infection who were of European or African descent. MEASUREMENTS: Time to AIDS, death, and death after AIDS and HIV-1 RNA level at study entry or soon after seroconversion. Data were combined with fixed-effects and random-effects models. RESULTS: Both the CCR5-Delta32 and CCR2-64I alleles were associated with a decreased risk for progression to AIDS (relative hazard among seroconverters, 0.74 and 0.76, respectively; P = 0.01 for both), a decreased risk for death (relative hazard among seroconverters, 0.64 and 0.74; P < 0.05 for both), and lower HIV-1 RNA levels after seroconversion (difference, -0.18 log(10) copies/mL and -0.14 log(10) copies/mL; P < 0.05 for both). Having the CCR5-Delta32 or CCR2-64I allele had no clear protective effect on the risk for death after development of AIDS. The results were consistent between seroconverters and seroprevalent patients. In contrast, SDF-1 3'A homozygotes showed no decreased risk for AIDS (relative hazard for seroconverters and seroprevalent patients, 0.99 and 1.03, respectively), death (relative hazard, 0.97 and 1.00), or death after development of AIDS (relative hazard, 0.81 and 0.97; P > 0.5 for all). CONCLUSIONS: The CCR5-Delta32 and CCR2-64I alleles had a strong protective effect on progression of HIV-1 infection, but SDF-1 3'A homozygosity carried no such protection.


Assuntos
Quimiocinas CXC/genética , Infecções por HIV/genética , HIV-1 , Receptores CCR5/genética , Receptores de Quimiocinas/genética , Síndrome da Imunodeficiência Adquirida/genética , Síndrome da Imunodeficiência Adquirida/mortalidade , Alelos , Quimiocina CXCL12 , Progressão da Doença , HIV-1/genética , Heterozigoto , Humanos , Modelos de Riscos Proporcionais , RNA/metabolismo , Receptores CCR2 , Análise de Regressão
2.
J Infect Dis ; 182(1): 311-5, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10882614

RESUMO

The SDF-1 3'A allelic polymorphism has been reported to influence either positively or negatively the progression of human immunodeficiency virus type 1 (HIV-1) disease. Therefore, the SDF-1 genotype of 729 HIV-1-infected individuals pooled from 3 distinct cohorts was determined. A statistically nonsignificant association between the SDF1-3'A/3'A genotype and accelerated disease progression was evident among seroconverters (n=319), but a striking correlation of decreased survival after either diagnosis of AIDS according to the 1993 definition or loss of CD4(+) T cell counts <200 was observed. The relative hazards for SDF1-3'A/3'A homozygotes, compared with heterozygotes and wild-type homozygotes were 2.16 (P=.0047), for time from diagnosis according to the 1993 Centers for Disease Control and Prevention AIDS case definition (AIDS-'93) to death, and 3.43 (P=.0001), for time from CD4(+) T cells <200 to death. Because no difference in survival was observed after diagnosis according to AIDS-'87, the association of the SDF1-3'A/3'A genotype with the accelerated progression of late-stage HIV-1 disease appears to be explained for the most part by the loss of CD4(+) T lymphocytes.


Assuntos
Síndrome da Imunodeficiência Adquirida/genética , Quimiocinas CXC/genética , HIV-1 , Síndrome da Imunodeficiência Adquirida/diagnóstico , Síndrome da Imunodeficiência Adquirida/imunologia , Síndrome da Imunodeficiência Adquirida/mortalidade , Adulto , Contagem de Linfócito CD4 , Quimiocina CXCL12 , Quimiocinas CXC/imunologia , Estudos de Coortes , Cresóis , Progressão da Doença , Combinação de Medicamentos , Formaldeído , Marcadores Genéticos , Genótipo , Humanos , Masculino , Polimorfismo Genético , Prognóstico , Resorcinóis , Taxa de Sobrevida , Viremia/etiologia
3.
Nat Med ; 3(10): 1160-2, 1997 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9334732

RESUMO

Entry of human immunodeficiency virus type 1 (HIV-1) into target cells requires both CD4 (ref. 1, 2) and one of a growing number of G-protein-coupled seven-transmembrane receptors. Viruses predominantly use one, or occasionally both, of the major co-receptors CCR5 or CXCR4, although other receptors, including CCR2B and CCR3, function as minor co-receptors. CCR3 appears critical in central nervous system infection. A 32-base pair inactivating deletion in CCR5 (delta 32) common to Northern European populations has been associated with reduced, but not absolute, HIV-1 transmission risk and delayed disease progression. A more commonly distributed transition causing a valine to isoleucine switch in transmembrane domain I of CCR2B (64I) with unknown functional consequences was recently shown to delay disease progression but not reduce infection risk. Although we confirm the lack of association of CCR2B 64I with transmission, we cannot confirm the association with delayed progression. Although subjects with CCR5 delta 32 defects had significantly reduced median viral load at study entry, providing a plausible explanation for the association with delayed progression, this association was not seen with CCR2B 64I. Further studies are needed to define the role of CCR2B64I in HIV pathogenesis.


Assuntos
Síndrome da Imunodeficiência Adquirida/genética , Síndrome da Imunodeficiência Adquirida/transmissão , HIV-1 , Polimorfismo Genético , Receptores CCR5/genética , Receptores de Quimiocinas/genética , Síndrome da Imunodeficiência Adquirida/mortalidade , Primers do DNA , HIV-1/isolamento & purificação , HIV-1/fisiologia , Humanos , Reação em Cadeia da Polimerase , RNA Viral/sangue , Receptores CCR2 , Taxa de Sobrevida , Fatores de Tempo
5.
Nat Med ; 3(3): 338-40, 1997 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9055864

RESUMO

Cellular entry of human immunodeficiency virus type 1 (HIV-1) requires binding to both CD4 (ref, 1, 2) and to one of the chemokine receptors recently discovered to act as coreceptors. Viruses that infect T-cell lines to form syncytia (syncytium-inducing, SI) are frequently found in late-stage HIV disease and utilize the chemokine receptor CXCR-4; macrophage-tropic viruses are non-syncytium-inducing (NSI), found throughout disease and utilize CCR-5 (ref. 3-11). We postulated that CCR-5 gene defects might reduce infection risk in seronegative subjects and prolong AIDS-free survival in seropositive subjects with NSI but not SI virus. Homozygous (delta ccr5/delta ccr5) and heterozygous (CCR5/delta ccr5) CCR-5 deletions (delta ccr5) were found in 7 (2.7%) and 51 (19.5%), respectively, of 261 seronegative subjects from the San Francisco Men's Health Study. CCR-5/delta ccr5 genotype was identified in 33 of 172 (19.2%) nonprogressors and 25 of 234 (10.7%) progressors from the seropositive arm of this cohort. The delta ccr5 allele conferred a significant protective effect against HIV-1 infection (P = 0.001) and a survival advantage against disease progression (P = 0.02). Although both progressing and nonprogressing CCR5/delta ccr5 subjects were identified, a distinct survival advantage was shown for those with NSI virus (P < 0.0001). Thus, the protective effect of delta ccr5 against disease progression is lost when the infecting virus uses CXCR-4 as a coreceptor.


Assuntos
Linfócitos T CD4-Positivos/virologia , Infecções por HIV/virologia , HIV-1/genética , Receptores de Citocinas/genética , Receptores de HIV/genética , Linhagem Celular , Infecções por HIV/transmissão , Homozigoto , Humanos , Mutação , Receptores CCR5
6.
J Pediatr ; 127(4): 544-9, 1995 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7562274

RESUMO

OBJECTIVE: To study the role of host genotype in pediatric infection with human immunodeficiency virus type 1 (HIV-1) and progression to acquired immunodeficiency syndrome (AIDS). METHODS: Human leukocyte antigen (HLA) class II and complement C4 genotypes were determined by means of molecular genetic techniques for 243 black children born to HIV-1-infected mothers in New York City and San Francisco. Survival, cumulative incidences of opportunistic infections and encephalopathy, and rates of CD4+ T cell decline were compared in children of different genotypes. RESULTS: Among HIV-1-infected children, the HLA-DR3 haplotype (DRB1*0301-DQA1*0501-DQB1*0201) was associated with increased incidence of encephalopathy, faster rate of CD4+ cell decline, and death before 2 years of age. Deletion of the C4A gene was independently associated with increased incidences of encephalopathy and early death. DPB1*0101 was associated with survival to at least 2 years of age. The presence of DQB1*0604 was associated with increased risk of HIV infection. CONCLUSIONS: These results are consistent with previously reported associations between HLA genotypes and faster progression to AIDS among HIV-infected adults. The DR3 haplotype and C4A deletion may reflect the same underlying mechanism of susceptibility in that the DR3 haplotype is in linkage disequilibrium with other C4A null alleles. In addition, the class II locus DPB1 may have an independent effect on survival.


Assuntos
Síndrome da Imunodeficiência Adquirida/virologia , Progressão da Doença , Genótipo , Soropositividade para HIV/virologia , HIV-1/isolamento & purificação , Alelos , Linfócitos T CD4-Positivos , Criança , Pré-Escolar , Soropositividade para HIV/transmissão , Antígenos HLA , Haplótipos , Humanos , Lactente , Estudos Prospectivos , Estudos Retrospectivos , Fatores de Risco , Taxa de Sobrevida
9.
Artigo em Inglês | MEDLINE | ID: mdl-1856793

RESUMO

To evaluate whether host genotype influences disease progression among persons infected with human immunodeficiency virus type 1 (HIV-1), molecular techniques were used to determine genotypes at immune response loci for 114 HIV-1-infected homosexual/bisexual white men in the San Francisco Men's Health Study. Candidate genes evaluated were HLA-DQA1 and -DRB1, complement C4A and C4B, alpha- and beta-interferons, and the heavy chain of immunoglobulin gamma 1. Of the 114 men, 29 were asymptomatic, 21 were symptomatic men and AIDS patients (p = 0.02). Specifically, the HLA haplotype DRB1*0702-DQA1*0201 was associated with absence of symptoms (p = 0.003). Conversely, the frequency of the complement C4B-L allele was higher among patients with symptoms or with AIDS than among asymptomatic subjects (p = 0.02). These results suggest that genes in or near the major histocompatibility complex may influence the rate of disease progression among HIV-1-infected men.


Assuntos
Síndrome da Imunodeficiência Adquirida/epidemiologia , Genótipo , Complexo Relacionado com a AIDS/epidemiologia , Complexo Relacionado com a AIDS/genética , Complexo Relacionado com a AIDS/imunologia , Síndrome da Imunodeficiência Adquirida/genética , Síndrome da Imunodeficiência Adquirida/imunologia , Adulto , Alelos , Frequência do Gene , Antígenos HLA-DQ/genética , Cadeias alfa de HLA-DQ , Antígenos HLA-DR/genética , Cadeias HLA-DRB1 , Antígenos de Histocompatibilidade Classe II/genética , Humanos , Masculino , São Francisco/epidemiologia
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