H-2 GENES AND RESISTANCE TO INFECTION WITH HELIGMOSOMOIDES-POLYGYRUS IN SELECTIVELY BRED MICE

Two lines of mice bred selectively for high resistance (RH) and suscep tibility (SL) to reinfection with Heligmosomoides polygyrus demonstrat ed disparate levels of resistance to infection but did not differ in t he frequency of H-2 antigens when assayed with antisera against antige ns of 5 inbred H-2 haplotypes, The selected RH and SL mice were crossb red with, and backcrossed to, the inbred CBA mice. F1 mice from crosse s between RH and CBA were as resistant to reinfection with H. polygyru s as their RH parents. F1 mice from crosses between SL and CBA were mo re resistant than either of their parents. BC1 mice were either positi ve or negative for H-2 antigens from RH and SL mice, BC1 mice that wer e positive for RH H-2 antigens were more resistant to infection than t heir negative littermates, but they were significantly more susceptibl e to infection with H. polygyrus than their F1 parents. These results demonstrated that genes within and mapped outside H-2 complex control the level of resistance to H. polygyrus in the selected mice and sugge sted that selective breeding of mice for resistance fixed the relevent genes in and outside the H-2 complex. (C) 1997 Australian Society for Parasitology.