PRF1 and chronic obstructive pulmonary disease: Moreover, a decline of lung function in COPD patients is associated with a high percentage of T cells that express CXCR3 [115], suggesting that CXCL9, CXCL10, and CXCL11 may be involved in the recruitment of T cells and the subsequent immune mediated lung damage observed in COPD, through the production of perforins and granzyme B [116].