We found that the levels of expression of genes involved in allergy development and innate immunity, including those encoding CLC, MS4A3, DEFA3, DEFA4, IL8RA, and IL8RB, were lower in PBMCs from IgG4-RD patients than from healthy controls. Here, CXCR2 is linked to immunoglobulin G4-related sclerosing disease.