| Title: | B cell response during infection with the MAT a and MAT alpha mating types of Cryptococcus neoformans |
| Author(s): | Rodrigues AR; Heise N; Previato JO; Mendonca-Previato L; Pecanha LM; |
| Address: | "Instituto de Microbiologia Professor Paulo de Goes, CCS, Bloco I, Universidade Federal do Rio de Janeiro, Cidade Universitaria, Ilha do Fundao, Rio de Janeiro, RJ 21944-570, Brazil" |
| DOI: | 10.1016/j.micinf.2004.09.009 |
| ISSN/ISBN: | 1286-4579 (Print) 1286-4579 (Linking) |
| Abstract: | "In the present study, we compared the B cell response of BALB/c and C57Bl/6 mice during Cryptococcus neoformans infection. This response was investigated using virulent serotype D forms of mating types alpha and a (MAT alpha and MAT a). C57Bl/6 mice showed massive (mainly cerebral) infection by both types, while BALB/c were resistant to infection. Some resistance of C57Bl/6 mice was induced by previous immunization with the capsular polysaccharide from MAT alpha. Passive immunization of C57Bl/6 mice with purified antibody (Ab) obtained from capsular polysaccharide-immunized mice also increased resistance to infection. Both mouse strains showed comparable low IgM response to the capsular polysaccharide from MAT alpha, and only C57Bl/6 mice produced IgM to the polysaccharide of MAT a. Comparable levels of different immunoglobulin (Ig) isotypes against capsular components of MAT alpha and MAT a were detected, and the response of C57Bl/6 mice was higher when compared to that of BALB/c mice. FACS analysis indicated an increase in the percentage of a high-granulosity (side-scatter) splenic subpopulation and in the percentage of splenic Gr-1+ cells in infected C57Bl/6 mice. In addition, the percentage of follicular splenic B cells was decreased after C. neoformans infection of C57Bl/6 mice. This response was more pronounced when we investigated infection induced by the MAT a mating type. Taken together, our results indicate that capsular polysaccharide derived from MAT alpha and MAT a types of C. neoformans have a stimulatory effect upon B cells but that there is no correlation between resistance of BALB/c mice and Ab production. However, the increase in resistance of C57Bl/6 mice parallels the production of Abs and a major change in splenic cell populations" |
| Keywords: | "Animals Antibodies, Protozoan/blood B-Lymphocytes/*immunology Cryptococcosis/*immunology Cryptococcus neoformans/genetics/*immunology Disease Susceptibility Female Immunization Immunoglobulin M/biosynthesis/blood Lymphocyte Count Male Mating Factor Mice M;" |
| Notes: | "MedlineRodrigues, Adila Regina T Santos Heise, Norton Previato, Jose Osvaldo Mendonca-Previato, Lucia Pecanha, Ligia M T eng Comparative Study Research Support, Non-U.S. Gov't France 2005/02/18 Microbes Infect. 2005 Jan; 7(1):118-25. doi: 10.1016/j.micinf.2004.09.009. Epub 2004 Nov 26" |
