CXCL2 and psoriasis: In addition, mice deficient in MKP1 overproduce pro-inflammatory cytokines, and MKP1 knockout mice are highly susceptible to imiquimod-induced psoriasis, in which enhancement of p38 phosphorylation and increased Cxcl1 and Cxcl2 expression are also observed (Zhao et al., 2018).