Multiplex analysis of circulating cytokines in the sera of patients with different clinical forms of visceral leishmaniasis

Background: The clinical spectrum of visceral leishmaniasis (VL), a chronic intracellular parasitic disease, ranges from a subclinical, asymptomatic infection to severe clinical disease (kala-azar). In experimental leishmaniasis, mice that have a Th1 response to infection tend to have limited disease while a Th2 response is associated with disease progression. Humans with VL most often have mixed rather than polarized responses. However, most clinical studies have used methods that require a relatively large sample volume, thus limiting their scope. Measuring multiple cytokine levels in blood samples using a multiplexed microsphere assay (MMA) may be useful to further evaluate the Th1/Th2 paradigm in humans. Methods: Bangladeshi individuals (n = 120) living in in area endemic for NFL were categorized into one of the five clinical categories. Sera from these individuals were measured for levels of IL2, IL-4, IL-5, IL-6, IL-8, IL-10, IIA2, IFN-gamma, and TNF-alpha by multiplexed microsphere cytokine immunoassay. Results: Circulating IL-8, IL-10, and IL-12 differed significantly among the clinical groups. Persons with kala-azar lem on stra ted the highest niedian levels of IL-8 and IL-10 but lower median levels of IL-12. Conclusions: The MMA for cytokines is an extremely timeand sample-efficicrit method for characterizing cirCUlating cytokine levels in visceral lcishrnaniasis patients. (c) 2006 International Society kw Analytical Cytology