Mechanisms involved in the effects of γδ T cells in the MRL/lpr model were further explored in the Blk±.lpr mouse, in which Blk expression levels are reduced to levels comparable to those in individuals carrying a risk allele for BLK, which encodes B lymphoid kinase, a susceptibility gene for SLE, resulting in reduced gene expression. Here, BLK is linked to systemic lupus erythematosus.