No difference in in vitro susceptibility to HIV type 1 between high-risk HIV-negative Ethiopian commercial sex workers and low-risk control subjects.
Host factors such as increased beta-chemokine production, HIV-1 coreceptor expression level, and HIV-1 coreceptor polymorphism have been thought to influence susceptibility to HIV-1 infection. To determine the protective role of these factors in Ethiopians who remained HIV-1 uninfected, despite multiple high-risk sexual exposures, we studied 21 Ethiopian women who had been employed as commercial sex workers (CSWs) for five or more years. The HIV-1-resistant CSWs were compared with low-risk age-matched female controls who had a comparable CD4+ cell percentage and mean fluorescence intensity (MFI). Genetic polymorphism in the CCR5, CCR2b, or SDF-1 genes appeared not to be associated with resistance in the Ethiopian CSWs. Expression levels of CCR5 and CXCR4 on naive, memory, and total CD4+ T cells tended to be higher in the resistant CSWs, while the production of beta-chemokines RANTES, MIP-1alpha, and MIP-1beta by phytohemagglutinin (PHA)-stimulated peripheral blood mononuclear cells (PBMCs) was lower compared with low-risk HIV-1 negative controls. In vitro susceptibility of PHA-stimulated PBMCs to primary, CCR5-restricted, Ethiopian HIV-1 isolates was comparable between resistant CSWs and low-risk controls. In vitro susceptibility was positively correlated to CD4+ cell mean fluorescence intensity and negatively correlated to CCR5 expression levels, suggesting that infection of PBMCs was primarily dependent on expression levels of CD4 and that CCR5 expression, above a certain threshold, did not further increase susceptibility. Our results show that coreceptor polymorphism, coreceptor expression levels, beta-chemokine production, and cellular resistance to in vitro HIV-1 infection are not associated with protection in high-risk HIV-1-negative Ethiopian CSWs.
Ethio-Netherlands AIDS Research Project at the Ethiopian Health and Nutrition Research Institute, Addis Ababa, Ethiopia. tsehay@enarp.com
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Messele
T F
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Rinke de Wit
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Brouwer
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Aklilu
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Birru
A L
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Fontanet
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Schuitemaker
D
D
Hamann
D000328:Adult; D018791:CD4 Lymphocyte Count; D019742:Chemokines, CC / Q000378:metabolism / Q000494:pharmacology; D015331:Cohort Studies; D004198:Disease Susceptibility; D005002:Ethiopia; D005260:Female; D005434:Flow Cytometry; D018023:HIV Seronegativity; D015497:HIV-1 / Q000276:immunology*; D006801:Humans; D066298:In Vitro Techniques; D008875:Middle Aged; D011110:Polymorphism, Genetic; D019713:Receptors, CCR5 / Q000235:genetics / Q000378:metabolism; D018121:Receptors, Cytokine / Q000378:metabolism; D012307:Risk Factors; D011477:Sex Work
D019742:Chemokines, CC; D019713:Receptors, CCR5; D018121:Receptors, Cytokine