Immunogenic proteins of Leishmania major during mouse infection

Mice of different strains (C3H/He, A/Jax, DBA/2, BALB/c and CBA/Ca) were infected intracutaneously with Leishmania major. Antibody production was analysed on the antigens of the promastigote form of the parasite which had previously been separated by SDS-polyacrylamide gel electrophoresis and transferred to nitrocellulose sheets. The kinetics of IgG antibody production were determined and the major immunogenic proteins of the parasite were identified for each strain of mouse. It was found that: 1 Antibody directed against parasite proteins appeared in the blood in all mouse strains tested soon after the first week of infection and rose steadily for 5 to 12 weeks. 2 Qualitative individual variation within a given strain was commonly observed in the response to the various antigens. Each mouse strain synthesized IgG directed against a somewhat different spectrum of parasite proteins. Homologies in antigen recognition by pooled sera of five mice ranged from 54% to 79% from one mouse strain to another. Hybrid mice from a BALB/c X CBA cross (F1 generation) recognized essentially all antigens recognized by the two parents. Proteins of L. major with apparent molecular weights of 19 kD, 60 kD, 65 kD, 70 kD and greater than 100 kD were immunogenic in all strains of mice tested.