IL17A and psoriasis: In addition, Schuster et al. [47] found that although the deletion of S1PR4 will not reduce the production of IL-17 in IMQ psoriasis model mice, it can reduce CCL2, IL-6 and CXCL1 (an important vector of psoriasis immune response), also confirming that S1PR4 may be a target for reducing permanent inflammatory responses.