Increased expression of the Th1-inducing cytokines interleukin-12 and interleukin-18 in cerebrospinal fluid but not in sera from patients with Lyme neuroborreliosis.

Lyme neuroborreliosis is a complex disease with different clinical outcomes and where immunopathological mechanisms are probably involved. In this study, sera and cerebrospinal fluid (CSF) from 21 neuroborreliosis patients and 26 control patients were analyzed for the Th1-inducing cytokines, interleukin (IL)-12 and IL-18, and the Th2 associated, soluble CD30 (sCD30) by ELISA. The results showed an increased number of neuroborreliosis patients expressing IL-12 (p<0.05) and IL-18 (p<0.05) in the CSF when compared with the controls, but no indication of increased levels in the sera. Nor were there any differences regarding levels of sCD30 in the sera or the CSF, indicating a local Th1-generating milieu in the target organ of neuroborreliosis.