Specific immunity in rats inoculated with Trypanosoma brucei brucei derived from tsetse salivary glands and cultured in vitro.

Twenty rats were each immunized intraperitoneally with 1.25 X 10(7) formalin-fixed Trypanosoma brucei brucei (Stock EATRO 1969) derived from tsetse salivary glands and propagated in culture at 29 degrees C in their infective form for more than 1000 days. Another group, consisting of 10 rats, was similarly immunized with parasites of stock EATRO 999 derived from salivary glands of a tsetse fly and propagated in culture for more than 360 days. Immunized animals were resistant to homologous challenge with 10(4) cultured infective parasites. There was no cross protection between stocks and animals were susceptible to homologous infective tsetse bite challenge.