CD4 and idiopathic pulmonary fibrosis: Our analysis revealed an expansion of CD14+CD36hiCD84hi CCR2– monocytes in patients with IPF, an increase in FCRL5+ B cell in patients with CTD-ILDs and AEx of IPF, increased levels of IL-2R+ TIGIT+ LAG3+ CD4+ T cells in IPF, increased levels of CXCR3+ CD226+ CD4+ T cells in sarcoidosis, and increased levels of PD1+ TIGIT+ CD57+ CD8+ T cells in CTD-ILDs.