Figure 4.

Unspecific immunoglobulins (Igs) have no impact on the viability of S. mansoni NTS. NTS were cultured and maintained using hybridoma medium (HM) supplemented with 20% sIgM^-/-, Rag1^-/-, or wild-type mouse (WT) sera at 37°C in 5% CO₂ for four weeks. HM alone was used as a control. (A) Viability of NTS is not restored by the loss of soluble IgM (sIgM) or (B) Igs. Results are representative of at least three individual experiments. Each data point has been shown as mean ± SD of at least three technical replicates. (C) Loss of sIgM does not significantly influence the mortality of S. mansoni-infected mice. sIgM-deficient mice were infected by injecting 200 cercariae and survival of the animals was monitored on a weekly basis. (D) Worm maturation was not affected by the deficiency of sIgM. After ten weeks of infection, the animals were euthanized and mature worms from mesenteric veins were flushed out, enumerated and male/female ratio was determined. Shown data is the mean ± SD of worms per mouse. (E) Lack of sIgM does not affect the fecundity of the worm. Eggs from the liver were isolated and counted. (F) sIgM does not influence the egg-induced immunopathology of the worm. Liver sections (4 µm) from infected wild-type or sIgM^-/- mice were stained with Masson’s Blue and the diameter of 30-40 granulomas/section was measured microscopically (10x). Data shown is pooled data from five individual experiments (WT, n=28; sIgM^-/-, n=12). Each data point shows a single mouse. Mean ± SD is indicated with bars. p.t., post transformation. s.p., scoring point.