Fig. 2

Reduced pro-inflammatory and Th1 cytokine responses in L3 and L4 antigen extract re-stimulated splenocytes. Groups of wildtype BALB/c mice were either subcutaneously infected with larvae (L3, L4), i.v. injected with MF or implanted with L5 or adult worms. On day 42 pi, lymphocytes isolated from infected BALB/c mice were left unstimulated or cultured with 100 µg/ml of the Loa loa developmental stage antigen extract that was originally used to infect the mouse. Antigen stimulation in cell cultures of lymphocytes from naive BALB/c mice served as control. Re-stimulation assays were cultured for 48 h at 37 °C and 5% CO₂ and resulting levels of IL-27 (a), IL-12p70 (b), IL-2 (c) and IL-18 (d) were determined using the Luminex technology. Data show concentration (pg/ml) of the different cytokines from re-stimulated splenocytes of infected BALB/c mice (closed symbols, n = 6 per life stage/parasite antigen extract) and naive BALB/c mice (open symbols, n = 3 per parasite antigen extract). Cytokine levels were normalized by subtracting background levels of the comparable un-stimulated controls. Graphs show scatter plots with mean ± SEM. Statistically significant differences between the indicated groups were detected using the Friedman test followed by a Dunn’s multiple comparison test