Plasma cytokine levels and human papillomavirus infection at the cervix in rural Nigerian women

Introduction: We conducted a study to test the hypothesis that systemic dysregulation of Th1/Th2 cytokine levels was associated with detection of carcinogenic or overall human papillomavirus (HPV) at the cervix among 964 women residing in a rural village in Nigeria. Methods: Levels in plasma were measured for 19 cytokines, including Th1-like cytokines IL-2, IL-12 (p40), TNF-a, IFN-g; Th2-like cytokines IL-4, IL-5, IL-6, IL-10, IL-13; innate/inflammation cytokines IL-1a, IL-1b, IL-8, eotaxin, MCP-1, MIP-1a, and IL-7; and cell development cytokines G-CSF, VEGF, and IL-17. Analysis was restricted to 5 cytokines, TNF-α (Th1), IL-8 (Th2), eotaxin and MCP-1 (innate/inflammation), and G-CSF (cell development), whose levels were detected in 80% or more of the samples measured as well as had a coefficient of variation of <30%. Results: Strong correlations were noted between levels of eotaxin and TNF-α (r= 0.75), IL-8 and MCP-1 (r= 0.60), eotaxin and G-CSF (r= 0.44), and G-CSF and IFN-γ (r= 0.43). Detection of carcinogenic or non-carcinogenic HPV DNA was unrelated to cytokine levels, except for levels of eotaxin and TNF-α, which were inversely correlated, albeit weakly, with detection of any carcinogenic HPV (P= 0.048 and P= 0.067, respectively). In analyses stratified by age group, levels of eotaxin were inversely correlated with detection of any HPV DNA (P= 0.026) and carcinogenic HPV (P= 0.042) in older, but not younger, women. Conclusions: Our results do not support the hypothesis of association between systemic cytokine dysregulation and detection of HPV at the cervix in Nigerian women, but subgroup analyses raise questions about inverse associations between eotaxin and TNF-α in older women.