In IPF:↑* monocytes (CD15hi, CD36hi, CD84hi, CCR2-)↑ lymphocytes, IL2R+, TIGIT+, LAG3+, CD4+In CTD:↑ IgG mB cells,↑ FclR5+ B cellsIn 1 SLE-ILD:↑ Ratio CD28-/CD4+In Sarcoidosis with advanced lesions:↑ FcRl5 B cells, and CXCR3+, CD226+, CD4+ T cells. This evidence concerns the gene CD4 and idiopathic pulmonary fibrosis.