CD28 and idiopathic pulmonary fibrosis: The ratios of senescent CD28-CD57+ central memory (0.12% vs 0.02%; p<0.000 before vaccination; 0.12% vs 0.01%; p<0.00 after the 1st dose; 0.19% vs 0.00%; p<0.000 after the 2nd dose), effector memory (0.86% vs 0.02%; p<0.000 before vaccination; 0.81% vs 0.05%; p<0.000 after the 1st dose; 0.78% vs 0.02%; p<0.000 after the 2nd dose), as well as TEMRA γδ Tc (2.07% vs 0.26%; p<0.000 before vaccination; 2.18% vs 0.57%; p<0.000 after the 1st dose; 2.38% vs 0.34%; p<0.000 after the 2nd dose) cells were elevated in the IPF group (Heat map 4., Supplementary Table 11; PCA 10-12; Supplementary Data).