title: HLA-Bw4-B*57 and Cw*18 alleles are associated with plasma viral load modulation in HIV-1 infected individuals in Salvador, Brazil.
abstract: Host genetic factors play an important role in mediating resistance to HIV-1 infection and may modify the course of infection. HLA-B alleles (Bw4 epitope; B*27 and B*57) as well as killer cell immunoglobulin-like receptors have been associated with slow progression of HIV-1 infection.
  
  
  OBJECTIVE
  To evaluate the association between serological epitopes HLA-Bw4 and HLA-Bw6 and prognostic markers in AIDS.
  
  
  METHODS
  147 HIV-infected individuals in Bahia, Northeast Brazil, were genotyped for HLA class I locus. HLA class I genotyping was performed by hybridization with sequence-specific oligonucleotide probes following amplification of the corresponding HLA-A, HLA-B and HLA-C genes. Statistical analysis was performed using Fisher's exact and ANOVA tests for categorical and continuous variables, respectively.
  
  
  RESULTS
  We detected a significant association (χ2 = 4.856; p = 0.018) between the presence of HLA-Bw4 and low levels of viremia. Eighteen out of the 147 HIV-infected individuals presented viremia <1,800 copies/mL and 129 presented viremia > 2,000 copies/mL. Ninety and four percent (17/18) of all individuals with viremia < 1,800 copies/mL carried HLA-Bw4, compared to 67.4% (87/129) of individuals with viremia > 2,000 copies/mL. Additionally, we found a significantly higher frequency of B*57 (OR = 13.94; 95% CI = 4.19-46.38; p < 0.0001) and Cw*18 (OR = 16.15; 95% CI = 3.46-75.43; p < 0.0001) alleles, favoring the group with lower viremia levels, in comparison with those with higher viral load.
  
  
  CONCLUSIONS
  HLA-Bw4-B*57 and Cw*18 alleles are associated with lower level of viral load in HIV-infected Brazilian patients. These findings may help us in understanding the determinants of HIV evolution in Brazilian patients, as well as in providing important information on immune response correlates of protection for such population.
authors.affiliation: Hospital Universitário Professor Edgard Santos, UFBA, Brazil. edinete@yahoo.com
authors.forename: Edinete Melo da
authors.initials: EM
authors.lastname: Silva
authors.forename: Angelina Xavier
authors.initials: AX
authors.lastname: Acosta
authors.forename: Eduardo José Melo
authors.initials: EJ
authors.lastname: Santos
authors.forename: Eduardo Martins
authors.initials: EM
authors.lastname: Netto
authors.forename: Denise Carneiro
authors.initials: DC
authors.lastname: Lemaire
authors.forename: Adriano Silva
authors.initials: AS
authors.lastname: Oliveira
authors.forename: Carolina Matos
authors.initials: CM
authors.lastname: Barbosa
authors.forename: Maria Teresita
authors.initials: MT
authors.lastname: Bendicho
authors.forename: Bernardo
authors.initials: B
authors.lastname: Galvão-Castro
authors.forename: Carlos
authors.initials: C
authors.lastname: Brites
mesh_terms: D000328:Adult; D000368:Aged; D000483:Alleles; D018791:CD4 Lymphocyte Count; D018450:Disease Progression; D005260:Female; D005819:Genetic Markers; D005838:Genotype; D015658:HIV Infections / Q000097:blood / Q000821:virology*; D015497:HIV-1 / Q000235:genetics* / Q000276:immunology; D015235:HLA-B Antigens / Q000097:blood*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D019562:Viral Load; D014766:Viremia / Q000097:blood*; D055815:Young Adult
chemical_list: D005819:Genetic Markers; D015235:HLA-B Antigens; C042388:HLA-Bw4 antigen