The relationship between circulating and intestinal Heligmosomoides polygyrus-specific IgG(1) and IgA and resistance to primary infection

Specific serum and intestinal immunoglobulin (Ig)G(1) and IgA responses to Heligmosomoides polygyrus wc re measured in a panel of seven inbred mouse s trains which exhibit 'rapid' (<6 weeks (SWRxSJL)F-1), 'fast' (< 8 weeks, SJ L and SWR), 'intermediate' (10-20 weeks, NIH and BALB/c) or 'slow' (>25 wee ks, C57BL/10 and CBA) resolution of primary infections. Mice with 'rapid', fast' or 'intermediate' response phenotypes produced greater serum and inte stinal antibody responses than those with 'slow' phenotypes. The F-1 hybrid s ((SWR x SJL)F-1) of two fast' responder strains showed the earliest antib ody response with maximum titres evident within 6 weeks of infection. There was a negative correlation between the serum IgG(1) responses and worm bur dens in individual mice within a number of mouse strains, and also between serum IgG(1) and IgA responses and worm burdens in the 'rapid' ((SWR x SJL) F-1) responder strain. The presence off IgG(1) in the gut was found to be d ue to local secretion rather than plasma leakage. Using Western immunoblott ing, serum IgG(1) from 'rapid' and 'fast' responder but not 'slow' responde r mice was found to react with low molecular weight antigens (16-18 kDa) in adult worm excretory/secretory products.