CD4 and interstitial lung disease: Previous studies suggested that activation of monocytes, macrophages, neutrophils, and CD4 + T helper (Th) 1 cells, and increased expression of CD4+CXCR4+ T cells and interferon (IFN)-γ contribute to the development of DM-ILD (Ishikawa et al., 2018; Wang et al., 2019b; Matsuda et al., 2020; Zuo et al., 2020).