Affiliation:
1. Department of Medicine, Indiana University School of Medicine, Indianapolis 46202-2879.
Abstract
Local immunity against acute pulmonary histoplasmosis was studied in the lung-associated lymph nodes of normal nonimmune mice infected intratracheally with live Histoplasma capsulatum yeasts. The phenotypes and distribution of cells in lung-associated lymph nodes and spleens were determined by flow cytometry. In addition, the immune responsiveness of these cells was evaluated by in vitro blastogenesis. Anti-H. capsulatum antibodies in serum and H. capsulatum antigen in tissue were measured by immunoassays. Cellular immune responses were greater in the lymph nodes than in the spleens. In lymph nodes 7 days after infection, a marked increase in the number of B lymphocytes caused the percentage to rise to 43%, compared with 26% in controls, and it remained elevated throughout the course of infection. A CD3+ cell that did not express CD4 or CD8 increased in number until it constituted 21% of lymph node cells, compared with 5% in controls, by day 14. The numbers of CD4+ and CD8+ T lymphocytes were modestly increased from days 7 to 35, but their percentages dropped because of the greater numbers of B lymphocytes and CD3+4-8- cells. Macrophages consistently constituted 2 to 3% of lymph node cells during the study. In spleens 7 days after infection, the percentage of macrophages in infected mice rose to 21%, compared with 9% in controls, but the total spleen cell number did not increase until day 14, when all cell subsets were nearly double in number. The in vitro blastogenic response of lymph node cells to H. capsulatum peaked at day 7, but spleen cell response was minimal during the course of infection. Histoplasma-specific serum immunoglobulin G antibodies reached peak levels by day 21 and remained high to the end of the study. In contrast, levels of antigen-specific immunoglobulin M antibodies were very low. These data suggest that antigen-specific immune responses occur in lung-associated lymph nodes and that this draining lymph node response may be an important component in host defense against Histoplasma lung infection.
Publisher
American Society for Microbiology
Subject
Infectious Diseases,Immunology,Microbiology,Parasitology
Reference35 articles.
1. Immunoregulatory responses in experimental disseminated histoplasmosis: Iymphoid organ histopathology and serological studies;Artz R. P.;Infect. Immun.,1979
2. NK1.1 thymocytes: adult murine CD4-, CD8- thymocytes contain an NK1.1, CD3+, CD5hi, CD44hI, TCR-Vl 8+ subset;Ballas Z. K.;J. Immunol.,1990
3. Rheumatoid arthritis associated with expanded populations of granular;Barton J. C.;Iymphocytes. Ann. Intern. Med.,1986
4. The pathogenesis of experimental pulmonary histoplasmosis: correlative studies of histopathology, bronchoalveolar lavage, and respiratory function;Baughman R. P.;Am. Rev. Respir. Dis.,1986
5. Immune globulin characterization of complement fixing antibodies in histoplasmin infection;Baum G. L.;Chest,1973
Cited by
28 articles.
订阅此论文施引文献
订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献