CD4+CD25+ T lymphocytes in human tonsils suppress the proliferation of CD4+CD25- tonsil cells.
Animal studies define CD4+CD25+ T cells as a subset that protect against autoimmune inflammation. We wanted to investigate whether CD4+CD25+ T cells from patients with recurrent tonsillitis could suppress the proliferation of other tonsil cells, in vitro, as this immunological tissue also may serve as a model for chronic inflammation. Tonsil CD4+CD25+ cells markedly suppressed the proliferation of CD4+CD25- T cells in Concanavalin A-stimulated cocultures compared with cultures containing CD4+CD25- T cells only. The suppression exerted by the CD4+CD25+ cells was abrogated if these cells were irradiated before coculture or if interleukin (IL)-2 was added to the culture medium. CD4+CD25+ T cells proliferated poorly in response to mitogen, when cultured alone. Substitution with CD4+CD25+ T cells isolated from peripheral blood, enriched by similar methods, did not downregulate the proliferation of CD4+CD25- responder cells from tonsils. The augmented suppressive ability of tonsil CD4+CD25+ T cells compared with cells of this phenotype from blood, on CD4+CD25- responder cells from tonsils, suggests that there may be a functional difference between CD25+ cells from the two locations. In conclusion, CD4+CD25+ T cells from inflamed tonsils distinctly suppressed T-cell responses to mitogen in vitro, pointing to a regulatory role for CD4+CD25+ cells retrieved from inflammatory reactions in humans.
Simark-Mattsson
C
C
Department of Endodontology/Oral Diagnosis, Göteborg University, Göteborg, Sweden. charlotte.simark@odontologi.gu.se
Dahlgren
U
U
Roos
K
K
D000293:Adolescent; D015704:CD4 Antigens / Q000276:immunology*; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology*; D002455:Cell Division / Q000276:immunology; D018920:Coculture Techniques; D005260:Female; D005434:Flow Cytometry; D006801:Humans; D008213:Lymphocyte Activation / Q000276:immunology; D016131:Lymphocyte Subsets; D008297:Male; D014066:Palatine Tonsil / Q000276:immunology*; D015375:Receptors, Interleukin-2 / Q000276:immunology*
D015704:CD4 Antigens; D015375:Receptors, Interleukin-2