title: CCR5 receptor expression is down-regulated in HIV type 2 infection: implication for viral control and protection.
abstract: HIV-2 is known to display an attenuated phenotype in vivo with prolonged time to disease and decreased rate of transmission. Observational studies in Senegal have demonstrated protection from HIV-1 infection, although the putative mechanism for immunoprotection remains undefined. We evaluated HIV-2-seropositive women from a cohort of commercial sex workers in Dakar, Senegal and identified individuals with very low surface CCR5 receptor expression on CD4+ T cells. In vitro up-regulation of the CCR5 receptor was readily achieved. Down-regulation of the CCR5 was not correlated with activation markers (HLA-DR), beta-chemokine levels, or plasma viral loads. A correlation was observed with HIV-2-specific CD8+ T cell activity as measured by intracellular cytokine production. We postulate that down-regulation of the CCR5 receptor in HIV-2 infection contributes to slower disease course and to the protective mechanism against HIV-1 superinfection, mediated in part by HIV-2-specific cellular immune responses.
authors.affiliation: California Department of Health Services, Richmond, 94804, USA.
authors.forename: A
authors.initials: A
authors.lastname: Shea
authors.forename: Dieng A
authors.initials: DA
authors.lastname: Sarr
authors.forename: N
authors.initials: N
authors.lastname: Jones
authors.forename: L
authors.initials: L
authors.lastname: Penning
authors.forename: G
authors.initials: G
authors.lastname: Eisen
authors.forename: A
authors.initials: A
authors.lastname: Gueye-Ndiaye
authors.forename: S
authors.initials: S
authors.lastname: Mboup
authors.forename: P
authors.initials: P
authors.lastname: Kanki
authors.forename: H
authors.initials: H
authors.lastname: Cao
mesh_terms: D015496:CD4-Positive T-Lymphocytes / Q000378:metabolism; D018414:CD8-Positive T-Lymphocytes / Q000378:metabolism; D019742:Chemokines, CC / Q000097:blood; D016207:Cytokines / Q000032:analysis / Q000096:biosynthesis; D018450:Disease Progression; D015536:Down-Regulation; D005260:Female; D005786:Gene Expression Regulation; D015658:HIV Infections / Q000503:physiopathology* / Q000821:virology*; D015498:HIV-2; D006684:HLA-DR Antigens / Q000032:analysis; D006801:Humans; D019713:Receptors, CCR5 / Q000235:genetics / Q000378:metabolism*; D012675:Senegal; D019562:Viral Load
chemical_list: D019742:Chemokines, CC; D016207:Cytokines; D006684:HLA-DR Antigens; D019713:Receptors, CCR5