Effect of CD28 deficiency on γδ T cell development.

<p>(<b>A</b>) Phenotypic analysis of CD28^+/+ and CD28^−/− mice. Dot plots show representative TCRγδ versus CD3 staining profiles on gated DN thymocytes, DN pLN cells and DN splenocytes. Numbers within the two-color plots represent the percentage of TCRγδ⁺ CD3⁺ cells in the gate. The mean cell number ± SEM for each tissue and genotype are displayed above the two-color plots. (<b>B</b>) Bars represent the mean number ± SEM of DN TCRγδ⁺ cells in the thymus, pLNs and spleen of CD28^+/+ (n = 4 to 8) and CD28^−/− (n = 4 to 8) mice. *<i>p≤0.05,</i> **<i>p≤0.01</i> and <i>#p≤0.001</i>. (C) Representative histograms comparing CD3 and CD5 levels on γδ (TCRγδ⁺) thymocytes from CD28^+/+ (n = 8) and CD28^−/− (n = 8) mice. (D) Representative histograms comparing the percentages of Vγ1⁺ and Vγ4⁺ γδ thymocytes from CD28^+/+ (n = 8) and CD28^−/− (n = 8) mice.