title: CCR2 and CCR5 genotypes in HIV type 1-infected adolescents: limited contributions to variability in plasma HIV type 1 RNA concentration in the absence of antiretroviral therapy.
abstract: In HIV-1-infected individuals, plasma viral RNA concentration as well as preservation of CD8+ naive T cells can vary by age. Host genetic factors previously shown to mediate HIV-1 pathogenesis in adults and children may operate differently in HIV-1-infected adolescents. Our PCR-based haplotyping of genetic variants at the loci encoding CC (beta) chemokine receptor 2 (CCR2) and CCR5 revealed nine haplotypes (designated A through G*2) in 179 seronegative and 228 seropositive adolescent participants from the Reaching for Excellence in Adolescent Care and Health (REACH) Study of the Adolescent Medicine and HIV/AIDS Research Network. The influence of CCR2-CCR5 haplotypes and genotypes on plasma HIV-1 RNA level was assessed in 207 AIDS-free seropositive individuals (mostly African-American females) who either did not receive therapy or had discontinued therapy for 6-12 months during initial follow-up between 1996 and 1999. The CCR2-64I-coding haplotype F*2 and the infrequent CCR5 Delta32-bearing haplotype G*2 had negligible impact on HIV-1 RNA level (p > 0.83) and CD4+ T cell counts (p > 0.30). In contrast, nine carriers of the E/E genotype had significantly higher (p = 0.007) plasma HIV-1 RNA level and slightly reduced CD4+ cell counts (p = 0.15) compared with those not carrying E/E or F*2 or G*2. The effect of E/E on HIV-1 RNA was stronger (p < 0.001) in a multivariable model adjusted for F*2 or G*2 (p = 0.45), race (p = 0.23), gender (p = 0.002), age (p = 0.26), and history of antiretroviral therapy (p < 0.001). Thus, among the major CCR2-CCR5 haplotypes/genotypes in chronically infected and predominantly African-American adolescents, only the E/E genotype appeared to influence early host-virus equilibration.
authors.affiliation: Division of Geographic Medicine, Department of Medicine, Schools of Public Health and Medicine, 1665 University Blvd., University of Alabama at Birmingham, Birmingham, AL 35294, USA.
authors.forename: Jianming
authors.initials: J
authors.lastname: Tang
authors.forename: Craig M
authors.initials: CM
authors.lastname: Wilson
authors.forename: Margaret
authors.initials: M
authors.lastname: Schaen
authors.forename: Angela
authors.initials: A
authors.lastname: Myracle
authors.forename: Steven D
authors.initials: SD
authors.lastname: Douglas
authors.forename: Richard A
authors.initials: RA
authors.lastname: Kaslow
mesh_terms: D000163:Acquired Immunodeficiency Syndrome / Q000188:drug therapy / Q000235:genetics* / Q000821:virology; D000293:Adolescent; D000328:Adult; D005838:Genotype; D015497:HIV-1; D006239:Haplotypes; D006801:Humans; D015999:Multivariate Analysis; D012367:RNA, Viral / Q000097:blood*; D054390:Receptors, CCR2; D019713:Receptors, CCR5 / Q000235:genetics*; D019707:Receptors, Chemokine / Q000235:genetics*
chemical_list: C515334:CCR2 protein, human; D012367:RNA, Viral; D054390:Receptors, CCR2; D019713:Receptors, CCR5; D019707:Receptors, Chemokine