CD4 and obstructive sleep apnea syndrome: As HAVCR2 was initially identified as a receptor expressed on interferon-γ-producing CD4+ Th1 cells and CD8+ cytotoxic T-cells (39), we performed Spearman correlation analysis for HAVCR2 and CD4/CD8A expression in OSA TME (Figure 3F) and observed a strong correlation between HAVCR2 and CD4 expressions.