Heligmosomoides polygyrus: resistance in inbred, outbred, and selected mice.

Mice reared selectively as high- and low- immune responders to reinfection with Heligmosomoides polygyrus showed extremes of resistance and susceptibility after infection when compared to inbred BALB/C, DBA/I, CBA, and SJL/J and outbred Quackenbush (Q) mice. The levels of anti-H. polygyrus total IgG and IgG1, IgG2b, and IgG3 isotype antibodies detected in serum from the seven strains of mice after secondary and the eosinophil leucocyte counts in blood after both primary and secondary infections correlated positively and strongly with the levels of protective immunity developed when evaluated using a resistance index formulated from the infectivity, fecundity, and length of adult worms recovered after infection.