Blastogenic responses of lymphocytes from mice immunized by sublethal infection with yeast cells of Histoplasma capsulatum.
AUTOR(ES)
Tewari, R P
RESUMO
Blastogenic responses of spleen cells to histoplasmin and ribosomal antigens and to the mitogens concanavalin A. phytohemagglutinin, and lipopolysaccharide were studied in normal and immunized mice (10(5) live yeast cells of Histoplasma capsulatum given by the subcutaneous route). Cells (10(6) per well) were cultured with and without antigens and mitogens in microtiter plates with RPMI 1640-5% heat-inactivated normal mouse serum for 72 h at 37 degrees C. Cells were harvested after a 16- to 18-h pulse with 1 microCi of [3H]thymidine (6.7 Ci/mol), and thymidine incorporation was measured by scintillation counting. The initial blastogenic response to concanavalin A (54 X 10(3) cpm) was suppressed (P less than 0.001) from 4 to 14 days post-immunization and returned to control levels on day 21. The response to phytohemagglutinin was suppressed up to 21 days. Lipopolysaccharide responses, however, were affected to a lesser degree. Blastogenic responses to histoplasmin and H. capsulatum ribosomes were similar on day 0 in normal and immune lymphocytes, but by day 4 cells from immunized mice were more responsive (P less than 0.01). The maximum response to H. capsulatum antigens was detected on day 42 and was 9- to 16-fold higher than in controls. These results demonstrate in vitro responses of primed lymphocytes on exposure to H. capsulatum antigens and suppressed responses to mitogens during early stages of the immune response.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=551432Documentos Relacionados
- Adoptive transfer of immunity from mice immunized with ribosomes or live yeast cells of Histoplasma capsulatum.
- Characterization of antigens from type A and B yeast cells of Histoplasma capsulatum.
- Delayed hypersensitivity responses of experimental animals to histoplasmin from the yeast and mycelial phases of Histoplasma capsulatum.
- Cellular immune responses to recombinant heat shock protein 70 from Histoplasma capsulatum.
- Respiration in the yeast and mycelial phases of Histoplasma capsulatum.