CXCR3 and idiopathic pulmonary fibrosis: Furthermore, a previous study suggested that CCR4 expression correlates with Th2 activation while CXCR3 expression correlates with Th1 cell activation and suggested that IPF patients are characterized by relatively equal ratios of CXCR3 and CCR4 expressing T cells whereas NSIP patients who have better prognoses are characterized by elevated expression levels of CXCR3.