RAP1A and chronic obstructive pulmonary disease: Single-cell RNA-seq data revealed increased Rap1a expression in monocytes from the lungs of chronic CS-exposed mice (Fig. 3j), consistent with increased expression of RAP1A levels in circulating monocytes from the peripheral blood of smokers (Fig. 3k) and monocyte-like macrophages in the bronchoalveolar lavage of COPD patients as determined by scRNA-seq (Fig. 1n).