title: Systemic mononuclear-cell vasculitis in MRL/Mp-lpr/lpr mice. A histologic and immunocytochemical analysis.
abstract: The cellular mechanisms governing the expression of mononuclear cell vasculitis are poorly understood. For determination of the precise sequence of events in the development of vasculitis in autoimmune MRL/lpr mice, histologic sections from 4-20-week-old mice were evaluated with a panel of cytochemical and immunohistochemical stains. The results show that vascular disease in MRL/lpr mice develops as follows: Thy 1+, Ly 1+, L3T4- T cells assemble around predominantly small-to-medium muscular arteries at approximately 8 weeks of age. At 12 weeks of age, an adventitial inflammatory focus forms, composed of large "reactive" mononuclear inflammatory cells adjacent to hypertrophied vascular smooth muscle cells (VSMCs). Blastic Thy 1+, Ly 1+, L3T4- T cells subsequently infiltrate the tunica media, and selective VSMC karyolysis results. Occasional cytotoxic/suppressor T cells, macrophages, and possibly NK cells are noted primarily distal to the infiltration site. The outer zone of the inflammatory infiltrate is composed of mature B cells and occasional B-cell precursors. These findings suggest that cellular constituents of the immune response mediate mononuclear cell vasculitis in MRL/lpr mice.
mesh_terms: D000818:Animals; D000945:Antigens, Differentiation, T-Lymphocyte; D000954:Antigens, Surface / Q000032:analysis; D001327:Autoimmune Diseases / Q000276:immunology / Q000473:pathology*; D005260:Female; D006649:Histocompatibility Antigens / Q000032:analysis; D006651:Histocytochemistry; D008214:Lymphocytes / Q000473:pathology*; D008232:Lymphoproliferative Disorders / Q000473:pathology; D008264:Macrophages / Q000473:pathology*; D008297:Male; D009131:Muscle, Smooth, Vascular / Q000473:pathology; D009504:Neutrophils / Q000473:pathology; D011971:Receptors, Immunologic / Q000032:analysis; D015375:Receptors, Interleukin-2; D013601:T-Lymphocytes / Q000276:immunology; D014657:Vasculitis / Q000276:immunology / Q000473:pathology*
chemical_list: D000945:Antigens, Differentiation, T-Lymphocyte; D000954:Antigens, Surface; D006649:Histocompatibility Antigens; D011971:Receptors, Immunologic; D015375:Receptors, Interleukin-2