We observed an increase in absolute counts of Treg cells (p = 0.030) (Figure 9B), CD4+ lymphocytes (p = 0.007; Figure 9E), and CD8+ lymphocytes (p = 0.026; Figure 9H) in the lung-draining lymph nodes of SIL-DMSO vs. CTRL-DMSO animals. Here, CD4 is linked to squamous cell intraepithelial neoplasia.