CXCL2 and hypersensitivity pneumonitis: Reflecting the significant reduction in expression of chemokines (CCL3, CCL4, CXCL1, CXCL2, and CXCL10) in the lung, the levels of alveolitis in PKD1mKO at 24 h after the S. rectivirgula exposure was also significantly reduced compared to the levels of alveolitis in WT.