Abstract
OBJECTIVE: To evaluate the relationship between cervical cytokine/chemokine concentrations and HIV-1 acquisition in peripartum Kenyan women. DESIGN: Nested case-control study. METHODS: Women participating in a prospective study of peripartum HIV acquisition in Kenya (the Mama Salama Study), were tested for HIV-1 at 1-3 month intervals during pregnancy and through 9 months postpartum. Cases positive for HIV-1 RNA during follow-up (N = 14), were matched 3 : 1 with HIV-negative controls (N = 42) based on age, marital status, partner HIV-1 status, transactional sex, and timing of cervical swab collection. Concentrations of five cytokines (IL-1β, IL-6, IL-10, IFNγ, and TNFα) and four chemokines (IL-8, C-X-C motif chemokine ligand 10 (CXCL10), macrophage inflammatory protein-1 α, and macrophage inflammatory protein-1 β) were measured from cervical swabs collected at the visit prior to HIV-1 diagnosis (cases) or matched gestational/postpartum time (controls). Cytokine/chemokine concentrations were compared between cases and controls using Wilcoxon rank-sum tests. Principal component analysis was used to create a summary score for closely correlated cytokines/chemokines. Associations with HIV-1 acquisition were analyzed using conditional logistic regression. Path analysis was used to evaluate hypothesized relationships between CXCL10, vaginal washing, Nugent score, and HIV-1 acquisition. RESULTS: Conditional logistic regression analysis demonstrated an association between increased concentrations of CXCL10 and HIV-1 acquisition (odds ratio = 1.74, 95% confidence interval 1.04, 2.93; P = 0.034). Path analysis confirmed a positive independent association between higher concentrations of CXCL10 and HIV-1 acquisition (path coefficient = 0.37, 95% confidence interval 0.15, 0.59; P < 0.001). CONCLUSION: HIV-1 acquisition was associated with increased cervical concentrations of CXCL10 in pregnant and postpartum women.