Figure 5
P28GST-immunization as well as schistosome infection of rats stimulate the production of T helper type 2–type cytokines. Rats were immunized with P28GST (two injections of 25 μg kg−1) or infected with living Schistosoma cercariae either 5 weeks (established infection) or 1 week (recent infection) before 2, 4, 6-trinitrobenzene sulfonic acid (TNBS) injection. TNBS colitis was induced in all groups, except negative control, which received ethanol solution. Animals injected with TNBS were considered as the positive control group. (a) Levels of interferon-γ (IFNγ) mRNA in the different groups of rats were assessed by quantitative PCR (qPCR). The levels of (b) interleukin (IL)-4, (c) IL-13, and (d) IL-10 mRNA assessed by qPCR were increased in P28GST-treated rats by comparison to rats with established infection. (e) Colons were removed after the killing of rats at day 39 and paraffin embedded. Representative images from colon tissues from rats immunized with P28GST or infected with living S. cercariae either 5 weeks (established infection) or 1 week (recent infection) and controls with (positive control) or without (negative control) TNBS. Paraffin-wax-embedded sections of the colon were stained with hematoxylin and eosin. Images are printed at the same final magnification ( × 20). (f) IL-5 mRNA expression was assessed by qPCR in the colons from the five groups of rats. Results are expressed as means±s.e.m.; n=20 rats per group *P<0.05; **P<0.01; NS, not significant.
