Studies have shown that the percentage of lymphocytes in BALF is significantly increased in patients with sarcoidosis (p < 0.001), and the percentage and count of BALF CD4+ are significantly higher than those in controls (p < 0.001, p < 0.004, respectively), while the percentage of CD8+ is significantly decreased (p < 0.007, p < 0.027, respectively), resulting in an increased BALF CD4+/CD8+ ratio (p < 0.007) [38]. The gene discussed is CD8A; the disease is sarcoidosis.