Genetic control of immunity to parasites: adoptive transfer of immunity between inbred strains of mice characterized by rapid and slow immune expulsion of Trichinella spiralis.

Adoptive transfer of immunity with immune mesenteric lymph node cells (IMLNC) was used to analyse the roles of immune and inflammatory events in determining the strain-characteristic time of expulsion of Trichinella spiralis from mice. Transfer of IMLNC within and between three rapidly responding strains (NIH, SWR, DBA1-all H-2q) resulted in accelerated worm expulsion, worm loss commencing before day 8 in each case. When NIH cells were transferred to slow-responder B10 congenic mice (B10G-H-2q) mice, immunity was evident at 8 days as a reduction in worm fecundity and only by 12 days as a reduction in worm numbers. A similar result was obtained when B10G cells were given to B10G recipients. In the reciprocal transfer, IMLNC from B10G transferred immunity to NIH as effectively and as rapidly as did NIH cells. Cells capable of transferring immunity were present in B10G mice as early as 4 days after infection, even though worm expulsion in this strain does not occur until after day 12. Thus following heterologous transfers of IMLNC, the time of worm expulsion was determined by the response of the recipient, and presumably by the ability to generate intestinal inflammatory changes. Earlier work has shown that the strain-characteristic time of worm expulsion is genetically determined, but not by H-2 linked genes. A corollary of the present work is that non-H-2 linked genes control the generation of intestinal inflammatory changes in T. spiralis infections. H-2 genes may control lymphocyte responsiveness to infection and the haplotype H-2q may determine a rapid response. Comparisons are made with the genetic control of resistance to Listeria monocytogenes and possible mechanisms are discussed.