Flow cytometric analysis of intestinal intraepithelial lymphocytes in a model of immunodeficiency in Wistar rats

MÁRQUEZ, M.GABRIELA; GALEANO ADRIANA; OLMOS SOFIA; ROUX M ESTELA

CYTOMETRY

Wiley

Lugar: New York; Año: 2000 vol. 41 p. 115 - 122

0196-4763

Background We have shown, in a rat model of immunodeficiency, permanent alterations in the thymus and in the gut-associated lymphoid tissues. We observed by immunohistochemistry an increase in the number of γ/δ+ T cells in the gut lamina propria and in the number of CD8α/α+, CD25+, γ/δ+ subpopulations of intestinal intraepithelial lymphocytes (iIEL). The aim of the present study was to analyze the isolated rat iIEL by flow cytometry. Materials and Methods Cells from mesenteric lymph nodes were examined in parallel with isolated iIEL. After staining with different antibodies, samples were run on a FACScan flow cytometer. Background staining was evaluated using isotype controls. Data analysis was performed using Lysys II software (Becton Dickinson) and WinMDI 2.3 software. Results 1) CD8α/β populations do not express TCRγ/δ, 2) CD8α/α+ populations express TCRγ/δ, and its percentage is significantly increased in R21, 3) CD8α/β and CD8α/α iIEL express TCRα/β, being the percentage of CD8α/α+ TCRα/β+ iIEL increased and the percentage of CD8α/β+ TCRα/β+ iIEL decreased in R21, and 4) CD8α/α as well as CD8α/β iIEL do express CD25 only in R21. Conclusions Considering the above results, we conclude that there exists an ?in situ? origin and extrathymic maturation of the CD8α/α+ iIEL in the intestinal epithelium. The increase of TCRγ/δ+ T cells may be triggered by the carbohydrate dextrin, to provide immune protection and control of inflammation at the intestinal level.