18,263 small airway epithelia cells from nonsmokers (NS) and 16,678 cells from smokers (S) were analyzed using single-cell 10x transcriptome. Differences in gene expression between smokers/nonsmokers as well as between cell type were all less than 10%, and there were no significant results. Notably, there was no change in ACE2 expression between smokers and nonsmokers. This may reflect a limitation of using single-cell RNA sequencing compared to bulk RNA sequencing as the results depend on the size and shape of the cell. However, these results are unique in that they elucidate the gene expression of individual cell types from a mixed population of cells.