Li and colleagues reported the results of single-cell transcriptomics of immune cells in bronchoalveolar lavage fluid during asthma exacerbation, which highlighted an increase in CD8+ T cells, monocytes, and macrophages and the distinct expression of proinflammatory cytokine genes and transcription factors associated with asthma exacerbation23. The gene discussed is CD8A; the disease is asthma.