CD4 and asbestosis: The incidence of pneumoconiosis complicated by TB in China is 14.8% [30], and it was found that the spontaneous release of IFN-γ in the alveolar lavage fluid of patients with asbestosis was greater than that in healthy people [31,32], and this release may be affected by the regulation of regulatory T cells such as CD4+ and CD8+ T-cells (mostly driven by CD4+ T-cell reactions), which were disturbed by silica [33,34,35,36].