| Autor: |
J O, Brubaker, Q, Li, A O, Tzianabos, D L, Kasper, R W, Finberg |
| Rok vydání: |
1999 |
| Předmět: |
|
| Zdroj: |
Journal of immunology (Baltimore, Md. : 1950). 162(4) |
| ISSN: |
0022-1767 |
| Popis: |
Bacteroides fragilis, a Gram-negative colonic bacterium, induces the formation of abscesses associated with intra-abdominal sepsis in humans. The singular ability of this organism to modulate abscess formation in experimental rodent models resides in the structurally distinct and ionically charged capsular polysaccharides A (PS A) and B (PS B). The regulation of abscess formation in animals is dependent on T lymphocytes. However, the manner in which PS A interacts with T cells remains unknown. We therefore tested the T cell stimulatory capacity of purified PS A on mouse and rat lymphocytes in cellular proliferation assays and found that the PS A molecule possesses mitogenic characteristics distinguishable from those of the polyclonal B cell activator LPS, the T cell mitogen Con A, and staphylococcal enterotoxin A superantigen. Further, PS A stimulated proliferation of normal mouse and rat lymphocytes differentially. Mouse B cells responded to PS A in a fashion that did not require exogenous APC function, while rat T lymphocyte responses to PS A required APC function derived from autologous or xenogenic feeder cells. Cellular depletion experiments showed that the CD4+ subset of rat spleen cells was the primary responder cell type to PS A in vitro. The differential stimulatory effects of PS A on mouse and rat lymphocytes may reflect its ability to stimulate different lymphocyte subsets in vivo through the activities of receptor/counter-receptor pairs present on responder lymphocytes and cognate APC. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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