CD72 and pulmonary fibrosis: A recent study by Zhao [66] demonstrated the contribution of CD22 and CD72 in a murine scleroderma model reporting a marked reduction in skin and lung fibrosis severity in CD22−/−, CD72−/−, and CD22−/−/CD72−/− mice in comparison to wild-type (WT) mice in the bleomycin-induced model.