Therefore, IL‐35 may interact with IL‐35R to transduce the phosphorylation signals by JAK2‐STAT1/4 signaling pathway, and then may enhance the inhibitory effect of LAIR1 to decrease the proliferation of mesangial cells, suppress the massive inflammation, and eventually inhibit progression of SLE‐LN. This evidence concerns the gene JAK2 and systemic lupus erythematosus.