Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0042384 (vasculitis)
 20,525 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A unique patient with type VIII Ehlers-Danlos syndrome and cutaneous vasculitis, resorptive osteolysis, and cardiac valvular disease is described. Collagen analyses identified morphologic and physical abnormalities of type I collagen. The patient's T lymphocytes could be propagated in vitro with type I collagen and produced a 60-kd lymphokine that bound this protein. Cellular autoimmunity to type I collagen may be responsible for this patient's intractable clinical condition.
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PMID:Intractable vasculitis, resorptive osteolysis, and immunity to type I collagen in type VIII Ehlers-Danlos syndrome. 195 24

Arterial smooth muscle cells (SMC) express major histocompatibility complex (MHC) class II antigens in experimental vasculitis and in the human atherosclerotic plaque. We have therefore studied the regulation of expression of MHC antigens in cultured human arterial SMC, using immunofluorescence, radioimmunoprecipitation and a quantitative cell-surface immunoradiometric assay. SMC expressed class I, but not class II, antigens on their cell surfaces under basal conditions. Treatment of SMC with recombinant or natural interferon-gamma (IFN-gamma) induced expression of class II antigens in the following order of intensity, DR greater than DP greater than DQ. HLA-DR protein in SMC showed the same MW as that synthesized by B-lymphoblastoid cells. Antibodies to IFN-gamma blocked all HLA-DR-inducing activity in mixed leucocyte reaction (MLR) supernatants and PHA-stimulated peripheral blood mononuclear cell (PBMC)-conditioned media, indicating that IFN-gamma is the only lymphokine secreted under these conditions that is capable of de novo induction of HLA-DR expression in SMC. Treatment of SMC with recombinant human tumour necrosis factor-alpha (TNF) or lymphotoxin (LT) did not per se induce class II antigen expression. However, both TNF and LT substantially enhanced IFN-gamma-induced expression of HLA-DQ while decreasing that of HLA-DP. TNF, but not LT, increased HLA-DR expression. Also, in dermal fibroblasts, IFN-gamma-induced HLA-DP expression was significantly inhibited in the presence of TNF. These data demonstrate that TNF and LT differentially modulate IFN-gamma-induced MHC antigen expression in mesenchymal cells. The fact that SMC can express MHC class II antigens suggests that this cell type may serve as an accessory cell in the initiation of the immune response.
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PMID:MHC class II antigen expression in human vascular smooth muscle cells is induced by interferon-gamma and modulated by tumour necrosis factor and lymphotoxin. 210 84

A possible role for retinal pigment epithelial cells (RPE) as local antigen presenting cells in immune inflammatory eye disease was investigated by studying the in vitro response of human RPE cells to stimulation with purified IFN-gamma or Con A induced lymphokine. RPE cells cultured with a single dose of 50-1000 u/ml IFN-gamma for up to 8 days to allow maximal Class II gene transcription, expressed HLA DP, DR and DQ antigens in a dose-dependent manner with 80% or more of cells positive for each antigen at the higher concentration. After removal of a suboptimal IFN-gamma stimulus, HLA-DR antigen expression persisted for at least 15 days. HLA-DP and DQ antigens persisted only after maximal IFN-gamma stimulation. Lymphokine from Con A stimulated lymphocytes induced higher levels of DR and DQ expression (80%) over DP (15%) implying complex interactions with other mediators present in the lymphocyte culture supernatant. Since RPE cells phagocytose and recycle autoantigen-rich retinal rod outer segments and co-express HLA DR and DQ Class II antigens in response to IFN-gamma stimulation, an immunoregulatory role in conditions in which retinal autoimmunity is implicated, such as chronic idiopathic posterior uveitis and retinal vasculitis is postulated for these cells.
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PMID:Human retinal pigment epithelial cells differentially express MHC class II (HLA, DP, DR and DQ) antigens in response to in vitro stimulation with lymphokine or purified IFN-gamma. 314 63

The studies reported here were designed to determine whether sera from various patients could prevent neutrophils from responding to the lymphokine, neutrophil migration inhibition factor from T lymphocytes (NIF-T). Neutrophils from healthy donors were treated with sera from 84 subjects and assayed for responses to NIF-T. Serum from 7 of 37 patients (19%) with rheumatoid arthritis, systemic lupus erythematosus, and various forms of vasculitis showed blocking activity. In contrast, none of 47 subjects, including healthy individuals and patients with spondylarthropathies, cancer, and active infections had a serum factor that prevented neutrophils from responding to NIF-T (P less than 0.01). Serum blocking activity occurred transiently in association with infection by Staphylococcus aureus in one patient with rheumatoid arthritis. Moreover, autologous neutrophils from this same patient showed impaired responses to NIF-T. Blocking activity could be eluted from protein A-Sepharose in three of three patients studied. In three of seven patients, blocking activity was detected in serum cryoprecipitates, with a recovery of 46 to 78% of the blocking activity and overall enrichment (purification) of 137- to 281-fold. Analysis of cryoprecipitates by sodium dodecyl sulfate-polyacrylamide gel electrophoresis showed the predominance of immunoglobulins M and G. In one patient, the serum blocking activity was not cryoprecipitable, and cryoprecipitates from a patient with essential cryoglobulinemia failed to prevent neutrophils from responding to NIF-T. Blocking activity was relatively specific for NIF-T, as there was no effect on F-met-leu-phe-induced chemotaxis of neutrophils. Serum blocking activity in patients with connective tissue disease showed some correlation (r = 0.50; P less than 0.01) with immune complexes detected by polyethylene glycol precipitation but not Clq binding. These studies suggest that the response of neutrophils to NIF-T may be blocked by serum, possibly as a result of immune complexes or autoantibodies found primarily in patients with connective tissue disease.
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PMID:Impaired response of neutrophils to a lymphokine by sera from patients with connective tissue disease. 664 68