Hymenolepis nana induced mastocytosis in mice

Abstract

Mice inoculated with 1000 Hymenolepis nana eggs did not show any significant mucosal mast cell (MMC) increases in duodena containing mature cysticercoids on day 4 of primary infection. However, on day 12, with adult worms in the ileum, prominent mucosal mastocytosis was seen in the ilea and, to a lesser degree, in the duodena; mastocytosis was due primarily to the intraepithelial MMC population. When the primary infection was terminated on day 4 (at the tissue phase) by administration of the anthelmintic drug praziquantel, the development of challenge cysticercoids was drastically impaired. Termination of primary infection after day 12 (luminal phase) resulted in improved development of challenge cysticercoids, but their excystment was aborted as the majority of them were still present in duodenal villi on day 12 of challenge. No adult worms were recovered from any of the challenged mice. MMC numbers on day 4 of challenge were comparable to those seen in duodena on day 12 of primary infection, but their numbers declined on day 12 of challenge and were comparable to those present in challenged ilea.