CD2 and dry eye syndrome: To finally clarify whether the interaction of CD58 and CD2 plays a key role in the costimulation of naive T cells by IFNγ-pretreated KCs, we analyzed the expression of IL-2, a costimulation-dependent cytokine (Fig. 3f).36,37 While the coculture of naive T cells with IFNγ-pretreated KCs clearly induced the production of IL-2 by the T cells, blocking CD58 or CD2 abolished KC-initiated IL-2 production (Fig. 3f).