Except our study that demonstrated the increased CCR2 gene expression of monocytes in OSA patients and under in vitro condition of intermittent hypoxia, a recent study has reported the increase of CCR2 gene expression and macrophage infiltration in carotid body of rat treated with chronic intermittent hypoxia for 7 days [39]. This evidence concerns the gene CCR2 and obstructive sleep apnea syndrome.