The expression levels of CD59, CD28, CCR7, CD270, Tim3, Eomes, lymphocyte activation gene‐3 (LAG3), TCRab and TIGIT were higher, while that of OX40, CD45RO, PD‐L1 and CD25 lower in cluster 09 in patients with acute pneumonia. The gene discussed is TNFRSF4; the disease is pneumonia.