IMMUNOLOGICAL RELATIONSHIPS DURING PRIMARY INFECTION WITH HELIGMOSOMOIDES-POLYGYRUS (NEMATOSPIROIDES-DUBIUS) - PARASITE-SPECIFIC IGG1 ANTIBODY-RESPONSES AND PRIMARY RESPONSE PHENOTYPE

IgG1 antibody responses to Heligmosomoides polygyrus were measured in eight mouse strains supporting acute ( < 8 weeks, SJL, SWR), intermedi ate (10-20 weeks, NIH, BALB/c) or chronic ( > 25 weeks, C57BL/0, CBA, C3H, AKR) primary infections. Mice supporting acute or intermediate in fections produced more intense antibody responses and total serum IgG1 concentrations were higher than in mice tolerating chronic infections . Positive correlations across mouse strains between the intensity of the antibody response and the percentage loss of worms in weeks 6 and 10 were established. No correlation was found between the response wit hin mouse strains and loss of worms by individual mice. Heavy infectio ns gave marginally higher antibody titres than low intensity infection s, but few significant differences were detected and it was concluded that infection intensity did not markedly influence the magnitude of t he antibody response. Male and female mice responded similarly despite the earlier loss of worms from females. No association was found betw een the primary response phenotype and recognition of particular antig ens in Western blot analysis, nor did intensity of infection or host g ender affect recognition. The possibility that immunomodulatory proper ties of adult worms may have had a differential influence on ability o f strains of contrasting response phenotype to mount IgG1 responses wa s discussed.