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N Tarcic

Publications and source records attributed to N Tarcic.

21 records · Page 2Linked to original sources

Control of autoimmune responses induced with modified self antigens.

Our previous studies suggested the TNP-modified syngeneic red blood cells induced a humoral autoimmune response in mice with a defective T cell function but not in normal mice. This report describes the continuation of these studies in which we elucidated the auto-delayed-type hypersensitivity response of mice with a defective T cell function. The mice were immunized with syngeneic TNP-modified spleen cells and challenged 14 d later by injecting syngeneic nonmodified con A-stimulated spleen cells into the footpad. The DTH response was assessed 24 hr later. Adult thymectomized, x-irradiated (250 rad), and Cy-treated mice injected with syngeneic TNP-Sc generated a DTH response when subsequently challenged with syngeneic blast cells but not when challenged with allogeneic blast cells. In contrast, normal mice treated in a similar manner did not exhibit a significant DTH response. The auto-DTH response of x-irradiated mice injected with TNP-Sc was abrogated when they were simultaneously transplanted with syngeneic spleen cells or nylon wool-passed syngeneic spleen cells. If the transplanted splenocytes had been treated with anti-Thy 1 serum and complement, they failed to abrogate the auto-DTH response of the above-mentioned mice. These results suggest that suppressor cells are programmed to control the autoimmune response induced with modified self antigens.

Aging↗

Restraint stress-induced changes in lymphocyte subsets and the expression of adhesion molecules.

The effect of restraint stress on the distribution of lymphocyte subsets were studied in young BALB/c male mice. Loss of whole body weight, a reduction in the weights of spleen and lymph nodes, and higher levels of serum corticosterone were evident after a single continuous restraint period of 16-18 h. Tissue sections of spleens from restrained animals revealed erythrocyte depletion in the contracted red pulp. Furthermore, there was a significantly higher proportion of CD4+, but not of CD8+, lymphocytes in the spleen. The proportion of the CD4+ subset was markedly diminished in peripheral blood, whereas no changes were detected in lymph nodes. Restraint resulted in enhanced allogeneic mixed lymphocyte reactivity and in altered expression of some CD4+, but not CD8+, splenocyte adhesion molecules (CD44, LFA-1 and VLA-4). Removal of circulating corticosteroids by surgical adrenalectomy abolished the restraint-induced changes in lymphocyte adhesion molecule expression. The findings suggest that the observed differences in lymphocytes subset distribution of lymphoid organs may be due to changes in the pattern of adhesion molecule expression.

Adrenalectomy↗