CD8A and chronic obstructive pulmonary disease: Furthermore, the proportion of CD8+ T cells was significantly 2-fold greater in the lung tissue of IPF patients than in the healthy lung tissue of donors (Table 2, Figure 2C) (p= 0.04; 27.7% [11.0–53.8] vs. 11.1% [4.4–27.4]; however these differences did not reach significance in comparison with those in COPD patients (p= 0.17; 23.5% [9.1–47.7]).