Abstract
The occurrence of acquired resistance and the kinetics of humoral immune responses to Angiostrongylus cantonensis infection were studied in eight inbred rat strains. Consequently, it was found that both BUF and ACI strains acquired less protective immunity than other strains and, conversely, Tokyo and NIG strains yielded higher resistance. The remaining strains showed various intermediate degrees of acquired resistance. Striking strain differences in pattern of reagin production were found; Tokyo was a high responder while ACI was a low responder. In contrast, the kinetics of indirect hemagglutination (IHA) antibody response was essentially the same in all the strains examined. The IHA antibody titers were generally high in both Tokyo and NIG. Histopathologically, ACI was distinct from NIG in that fibrotic reactions around the nodules of developing eggs in the lung parenchyma were almost undiscernible. These data suggest that genetic factors would be involved in acquired resistance and reaginic antibody responses to A. cantonensis infection in rats.
