Inhibition of the protective IgA response by ketotifen is related to the inflammatory reaction in the peritoneal cavity and intestinal mucosa of BALB/c mice infected with Trichinella spiralis.

Interleukin-5 (IL-5) production, eosinophilia, and IgA responses of BALB/c mice infected with Trichinella spiralis were measured in the peritoneal cavity and intestinal mucosa. Ketotifen, an anti-allergic compound, was used to control the inflammatory response. IgA responses differed against adult and muscle stages of the parasite and between the intestine and the peritoneal cavity. IL-5 and eosinophil production also differed between the intestine and the peritoneal cavity. The occurrence of parasite-specific IgA antibodies in the peritoneal cavity may reflect the migration of cells from the lamina propria. Following ketotifen treatment there was a reduction in the IL-5, eosinophilic, and IgA responses; these responses affected both the size of worms and the number of worms.