| Autor: |
Farstad, I. N., Halstensen, T. S., Lazarovits, A. I., Norstein, J., Fausa, O., Brandtzaeg, P. |
| Předmět: |
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| Zdroj: |
Scandinavian Journal of Immunology; Dec1995, Vol. 42 Issue 6, p662-672, 11p, 1 Diagram, 1 Chart, 4 Graphs |
| Abstrakt: |
Interactions between homing receptors on circulating leucocytes and endothelial addressins regulate tissue-specific cellular extravasation. Although integrin α4β7 appears to be the main receptor for gut-homing T lymphocytes, less is known about molecules mediating mucosal B cell homing. Expression of integrin α4β7 on B lymphocytes, B cell blasts, and plasma cells in human gut-associated lymphoid tissue (GALT; the Peyer's patches and appendix) and lamina propria was studied by multi-colour immunofluorescence applied on cryosections. Isolated mononuclear cells from the same tissue compartments were examined by flow cytometry and compared with peripheral blood B cells. Integrin α4β7 was expressed by IgA+ B cell blasts and plasma ceils (CD38high) in the lamina propria, B cell blasts in GALT, and sIgD+ B lymphocytes in peripheral blood. In contrast, GALT sIgD+ B lymphocytes were negative or only weakly positive for β4β7. These results suggested that B lymphocytes down-regulate α4β7 upon extravasation in GALT but up-regulate this integrin after antigen-priming. Thus, α4β7 may be a homing receptor also for B cell blasts extravasating in the gut lamina propria, where this integrin is maintained on plasma cells, perhaps as a local retention factor. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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