CD40LG and systemic lupus erythematosus: Our results showed that CD40L was primarily expressed by Vδ2 T cell subsets that had low TCR Vδ2 expression and that the level of CD40L expression by Vδ2 T cells from SLE patients was significantly higher than from HC (51.05 ± 13.04% vs. 24.80 ± 4.25%, p < 0.01) (Fig. 4A,B).