Abstract
Beginning at hatching, chicks were fed a Basal diet, without vitamin E or selenium (Se) or the same diet supplemented with vitamin E (100 IU/kg) and Se (0.2 ppm). The effect of these treatments on the expression of cell surface markers (CT-1a, CD3, CD4, CD8, sIgs, and Ia) defining specific thymocyte and peripheral blood leukocyte (PBL) subpopulations were examined using flow cytometric analyses. In parallel studies the effect of the dietary deficiencies on splenocyte proliferative responses to ConA or PHA stimulation was examined. The mean expression of CD3 and CT-1a per cell was increased while CD8 and CD4 expression was decreased on thymocytes from chicks fed the Basal diet. The proportion of double negative (CD4−, CD8−) thymocytes and single positive CD8± thymocytes was significantly decreased while single positive CD4± and double positive (CD4±, CD8±) thymocytes were significantly increased by the dietary vitamin E and Se deficiencies. The dietary deficiencies resulted in a decreased proportion of peripheral T cells and specifically decreased the number of CD4± PBL. The proliferative response to both ConA and PHA was impaired by the vitamin E and Se dietary deficiencies. The proliferative response could be fully reconstituted but only after vitamin E and Se supplementation for periods longer than 1 week. Plasma SeGSHpx and α-tocopherol levels paralleled the mitogen responsiveness observed. These results support the conclusion that vitamin E and Se deficiencies may affect both the maturation of specific lymphocyte subpopulations and the functional and proliferative capabilities of the peripheral lymphocytes.
Keywords:
- ANOVA - analysis of variance
- CD - Cornell D diet
- ConA - Concanavalin A
- CPM - counts per minute
- E/Se - Vitamin E and Se adequate diet
- FITC - fluoresceinyl 5-isothiocyanate
- MHC - major histocompatibility complex
- PBL - peripheral blood leukocytes
- PHA - phytohemagglutinin
- SCWL - Single Comb White Leghorn
- Se -selenium