The ratio of CD163-positive macrophages to Iba1-positive macrophages is low in the intima in the early stage of cutaneous arteritis

The etiology of polyarteritis nodosa (PAN) and localized PAN, including cutaneous arteritis (CA), remains unknown; however, initial endothelial damage has been implicated. The intima of the vasculitis lesions is predominantly infiltrated by innate-like bystander-activated CD8 T cells, in addition to the macrophages. Macrophages are among the major inflammatory cells involved in innate immunity and are classified into M1 and M2 subtypes. M1-type...