Open Accessγσ Lymphocytes in endocrine autoimmunity: evidence of expansion in Graves' disease but not in type 1 diabetes
Author(s) -
ROURAMIR I. C.,
ALCALDE L.,
VARGAS F.,
TOLOSA E.,
OBIOLS G.,
FOZ M.,
JARAQUEMADA D.,
PUJOLBORRELL R.
Publication year - 1993
Publication title -
clinical & experimental immunology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.329
H-Index - 135
eISSN - 1365-2249
pISSN - 0009-9104
DOI - 10.1111/j.1365-2249.1993.tb03394.x
Subject(s) - t cell receptor , autoimmunity , type 1 diabetes , cd3 , immunology , antigen , t lymphocyte , medicine , t cell , peripheral blood mononuclear cell , gamma delta t cell , endocrinology , autoimmune disease , antibody , diabetes mellitus , biology , cd8 , immune system , in vitro , biochemistry
SUMMARY Endocrine autoimmune disorders are mediated by T cell‐dependent responses to organ‐specific antigens, but the mechanisms initiating the process remain unknown. Lymphocytes whieh use the γδ heterodimer as T ceii receptor (TCR) for antigen constitute a distinct subset of T cells whose function remains elusive. In order to investigate their possible involvement in endocrine auloimmunity we have determined the proportion of γδ T cells in the peripheral biood of 23 patients with type 1 (insulin‐dependent) diabetes mellitus (type‐1 DM) and 30 patients with autoimmune thyrotoxicosis (Graves’ disease). T lymphocyte TCR expression was assessed by fluorescence‐activated flow eytometry on peripheral blood mononuclear cells using MoAbs UCHTI (CD3), TCR 51 (γδ TCR), WT31 and βF1 (αβ TCR) and both the percentage of T cells expressing γδ and the ratio γδ/αβ were calculated. In the diabetie patients γδ cells were not significantly different from (he control group (7.7 ± 54% versus 8.0 ± 5.5%) of T eells, P NS). There was no relation between the proportion of γδ lymphoeytes and the presence ol’ islet cell antibodies (ICA) in the sera. The Graves’ patients showed a tendency towards a higher proportion of γδ T lymphocytes than the controls (γδ/αβ ratios: 0.095 ± 0.047 versus 0.063 ± 0.022, P = 0 03). In 14 Graves’ patients the number of γδ were measured in paired samples of peripheral and inlrathyroidal lymphocytes, demonstrating an expansion of γδ within the thyroid glands (0.21 ± 0.3 versus 0.095 ± 0.047, P = 0.032). Immunohistochemical studies showed that γδ celts were scattered among the predominant αβ lymphoeytes infiltrating the thyroid gland and that they aeeount for 10% of intraepitheliai lymphocytes. No relation was found between the increase of γδ lymphocytes and any clinieai features.