CD4 and idiopathic pulmonary fibrosis: Five immunophenotypes were linked to a decreased IPF risk (Figure 5): CM CD4+ %CD4+ (OR = 0.97, 95% CI = 0.95–1.00, p = 0.028), TD CD4+ AC (OR = 0.87, 95% CI = 0.77–1.00, p = 0.044), CD4 on CD4+ (OR = 0.91, 95% CI = 0.85–0.98, p = 0.015), CD4 on CM CD4+ (OR = 0.90, 95% CI = 0.82–0.98, p = 0.012), and CD4RA on TD CD4+ (OR = 0.96, 95% CI = 0.93–1.00, p = 0.040).