Other immunohistochemical investigations [53] performed on nerve samples of inflammatory and noninflammatory polyneuropathic subjects revealed perineurium and endothelium MMP-2 positivity in all tissue sections, with a specific upregulation of stromal MMP-2 in chronic inflammatory demyelinating polyneuropathy (CIDP), and even higher levels in vasculitic neuropathies. The gene discussed is MMP2; the disease is chronic inflammatory demyelinating polyradiculoneuropathy.