FIG. 4.

Neutralization of IL-10, TGF-β, and G-CSF during preincubation prevents establishment of desensitization by Borrelia lysate. PBMC were untreated or were stimulated for 24 h in the presence of Borrelia lysate alone (Bb lysate) or additionally with anti-TGF-β (a-TGFβ; 1 μg/ml) and anti-IL-10 (a-IL-10; 10 μg/ml) monoclonal antibodies, and 1% anti-mu-G-CSF-sheep immunoglobulin G (a-G-CSF) or combinations of the neutralizing antibodies and serum. Controls were cultured without Borrelia lysate. After being washed, cells were restimulated with 10 μg of Borrelia lysate/ml for a further 24 h at 37°C. Cytokine amounts in supernatants were determined by ELISA. Data are expressed as the means ± SEM divided by the OD assessed by the MTT assay. The statistical significance is for comparison with the nontolerized cells. * represents a P value of <0.05 and *** represents a P value of <0.001 based on ANOVA followed by Dunnett's multiple comparison test. +, present; −, absent.