Expulsion of Nippostrongylus brasiliensis from the Intestine of Rats: Evidence for a Third Component in the Rejection Mechanism

Abstract

Mesenteric lymph node cells obtained from immunized donors caused the expulsion of transplanted damaged worms of Nippostrongylus brasiliensis in both non-irradiated and irradiated (400 rad) syngeneic recipients (DA strain). They did not cause the expulsion of transplanted damaged worms in syngeneic recipients irradiated at 750 rad, although in one experiment they did suppress worm egg production per female worm. It is clear that both non-irradiated cell recipients and recipients irradiated at 400 rad made an active contribution to worm expulsion. This third component is in addition to the humoral (worm damage by antibody) and cell-mediated components previously defined by the studies of Jones and Ogilvie [1971], Keller and Keist [1972] and Dineen et al. [1973b]. In a collateral study, using the production of plaque-forming cells in rat spleen following antigenic stimulation with sheep red blood cells, it was shown that there was considerable regeneration of immunological reactivity in rats immunized after irradiation at 400 rad during the time course (4–6 days) of the present studies. No such regeneration occurred in rats irradiated at 750 rad. The nature of the third component is currently under investigation.