These murine studies were consistent with a report that HPK1 expression was reduced in CD4+ T cells of systemic lupus erythematosus patients due to jumonji domain containing 3 (JMJD3)-mediated H3 lysine 27 trimethylation (H3K27me3) of the HPK1 promoter (Zhang et al., 2011). This evidence concerns the gene MAP4K1 and systemic lupus erythematosus.