Long-lasting cell-mediated immunity induced by a live Francisella tularensis vaccine.
The lymphocyte stimulation test was used to estimate specific cell-mediated immunity after vaccination with the live vaccine strain of Francisella tularensis. Nonvaccinated individuals and individuals vaccinated 1, 5 to 6, 7 to 8, and 9 years previously were tested. Lymphocytes from most vaccinees responded to an antigen preparation of the vaccine strain, and those vaccinated 9 years before testing responded to a similar extent as did vaccines in the other groups. A new technique was developed to study the presence of T lymphocytes among the stimulated cells. Stimulated cells were allowed to incorporate [14C]thymidine and were then fractionated into T and non-T lymphocytes. Most of the incorporation appeared in the fraction containing T lymphocytes. The data indicate that cell-mediated immunity endures for at least 9 years after vaccination with the live F. tularensis vaccine.
D000907:Antibodies, Bacterial / Q000032:analysis; D001428:Bacterial Vaccines / Q000276:immunology*; D005604:Francisella tularensis / Q000276:immunology*; D006801:Humans; D007074:Immunoglobulin G / Q000032:analysis; D007075:Immunoglobulin M / Q000032:analysis; D008213:Lymphocyte Activation; D013601:T-Lymphocytes / Q000276:immunology*; D013997:Time Factors; D014611:Vaccination; D014613:Vaccines, Attenuated
D000907:Antibodies, Bacterial; D001428:Bacterial Vaccines; D007074:Immunoglobulin G; D007075:Immunoglobulin M; D014613:Vaccines, Attenuated