Effect of parasitosis on allergic sensitization in rats sensitized with ovalbumin: interaction between parasitosis...

Some helminthic infections, especially nematode infections, may behave as allergens and induce allergic sensitization. In this study, the investigators explored whether infections with Syphacia muris and Aspiculuris tetraptera have any effect on the development of allergen-induced cytokine responses and serum total immunoglobulin E (IgE) levels in ovalbumin (OVA)-sensitized rats. Four groups of male Wistar rats were studied. OVA sensitization was generated in 2 groups of rats; the rats in 1 group were infected and those in the other group were not. On day 21 after sensitization, tumor necrosis factor-alpha, interleukin-10, and total IgE levels in serum samples of rats were measured by enzyme-linked immunosorbent assay. The results showed that average concentrations of tumor necrosis factor-a and interleukin-10 were significantly greater in the group of rats infected with parasites and sensitized to OVA compared with the group uninfected with parasites and sensitized to OVA (P=.043 and P=.046, respectively). Upon comparison of total IgE concentrations, the group of rats infected with parasites and given saline solution showed higher levels compared with the group uninfected with parasites and given saline (P=.004). In conclusion, the investigators were unable to show a protective effect of an existing parasitic infection against the development of allergic sensitization upon exposure to OVA.