Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0024141 (systemic lupus erythematosus)
 44,322 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Main components of kinin system, the arginine-esterase activity and proteinase inhibitors were estimated in blood serum of patients with nephrotic syndrome of various etiology (glomerulonephritis, amyloidosis, systemic lupus erythematous) and also in patients with latent nephritis and in healthy donors. Content of all the kinin system components (kallikreinogen, kininogen and kininase 1) proved to be increased in all the forms of nephropathy studied. Free kallikrein was found in blood serum of patients with nephrotic syndrome as distinct from healthy persons and patients with latent nephritis. The arginine-esterase activity, which shows the level of trypsin-like proteinases, was altered dissimilarly, depending on the nephrotic syndrome etiology: it was maximally increased in nephrotic syndrome of amyloid genesis and decreased in patient with systemic lupus erythematosus. High content of kallikrein and kininase I with simultaneous decrease in kininogen was typical for patients with severe form of nephrotic syndrome. Impairment of kidney in nephrotic syndrome was also characterized by an increase in alpha1-antitrypsin and in the total antitryptic activity, which reached the maximal value in nephrotic syndrome of the I degree and decreased at the II degree of the disease. In nephrotic syndrome content of alpha2-macroglobulin was maximally increased at the II degree of nephrotic syndrome and decreased in severe form of the disease. The primary alteration in content of proteinase inhibitors and high level of kinin system components were assumed to determine the conditions for activation of kinin system in blood serum and to impair the nephrotic syndrome pathogenesis, which was complicated by systemic manifestations. High content of kinin system components was apparently determined by the increased synthesis in liver tissue in response to inflammation and massive proteinuria; kininase I and alpha2-macrolgobulin, as proteins with high molecular weight, were likely to be selectively retained in blood circulation when the capillary penetration was increased.
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PMID:[State of the kinin system and level of serum proteinase inhibitors in latent nephritis and the nephrotic syndrome of different etiology]. 7 Jan 11

The presence of a human T-cell lymphotropic virus (HTLV)-related endogenous sequence, HRES-1, in the human genome has been documented. The HRES-1 genomic locus is transcriptionally active and contains open reading frames. Antibodies 232 and 233, specific for synthetic peptides pep14-24 and pep117-127, corresponding to two nonoverlapping HTLV-related regions in the longer open reading frame of HRES-1, recognize an identical 28-kDa protein in H9 human T cells. Thus, HRES-1 is a human endogenous retroviral sequence capable of protein expression. HRES-1/p28 is localized to the cytoplasm and nuclear bodies. While HTLV-I-specific antibodies react with HRES-1 peptides, antibody 233 cross-reacts with HTLV-I gag p24 protein. Three consecutive highly charged amino acid residues, Arg-Arg-Glu, present in both HRES-1 pep117-127 and HTLV-I gag p24 are likely to be the core of cross-reactive epitopes. The prevalence of antibodies to HRES-1 peptides pep14-24 and pep117-127 was determined in 65 normal blood donors and 146 patients with immunological disorders. Sera of patients with multiple sclerosis (19 out of 65, 29%), progressive systemic sclerosis (4 out of 17, 23%), systemic lupus erythematosus (4 out of 19, 21%), and Sjogren syndrome (2 out of 19, 10%) contained significantly higher HRES-1 peptide binding activity than sera of normal donors. Sera of patients with AIDS showed no specific binding to HRES-1 peptides. Nine of 30 HRES-1-seropositive patients showed immunoreactivity to HTLV-I gag p24. The data indicate that HRES-1/p28 may serve as an autoantigen eliciting autoantibodies cross-reactive with HTLV-I gag antigens.
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PMID:Human T-cell lymphotropic virus (HTLV)-related endogenous sequence, HRES-1, encodes a 28-kDa protein: a possible autoantigen for HTLV-I gag-reactive autoantibodies. 134 29

Antibodies to the Sm nuclear antigen are diagnostic of systemic lupus erythematosus (SLE). MRL/Mp-lpr/lpr mice develop a similar illness, and a proportion also develop anti-Sm. To understand better anti-Sm reactivity in this murine model, we have cloned the murine Sm-D autoantigen. One cDNA clone was 517 bp long with an open reading frame of 357 nucleotides, encoding a 13.3 kDa protein of 119 amino acids. At the nucleotide level, the murine Sm-D cDNA was 89.8% homologous with human Sm-D (94% in the coding region), yet there was identity at the protein level, including a Gly-Arg nine-fold repeated C-terminus motif. Southern blot analysis of PstI-digested genomic DNA from seven mouse strains demonstrated a 7.8 kb band in every strain; in addition, a 2.8 kb band was seen in AKR/J, LG/J and MRL/Mp-lpr/lpr. PCR amplification of genomic DNA showed a single Sm-D gene product of 360 bp, which indicated a lack of intervening sequences. The Sm-D protein is thus highly conserved in evolution, probably owing to its essential role in the physiology of the cell.
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PMID:The murine Sm-D autoantigen: multiple genes, genetic polymorphism, evolutionary conservation and lack of intervening sequences in the coding region. 138 35

We report the Ig H and L chain V region sequences from the cDNAs encoding a monoclonal human IgG anti-cardiolipin/ssDNA autoantibody (R149) derived from a patient with active SLE. Comparison with the germ-line V-gene repertoire of this patient revealed that R149 likely arose as a consequence of an Ag-driven selection process. The Ag-binding portions of the V regions were characterized by a high number of arginine residues, a property that has been associated with anti-dsDNA autoantibodies from lupus-prone mice and patients with SLE. The VH gene encoding autoantibody R149 was a somatically mutated variant of the 51P1 gene segment, which is frequently associated with the restricted fetal B cell repertoire, malignant CD5 B cells, and natural autoantibodies. These data suggest that in SLE patients a common antigenic stimulus may evoke anti-DNA and anti-cardiolipin autoantibodies and provide further evidence that a small set of developmentally restricted VH genes can give rise to disease-associated autoantibodies through Ag-selected somatic mutations.
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PMID:A human systemic lupus erythematosus-related anti-cardiolipin/single-stranded DNA autoantibody is encoded by a somatically mutated variant of the developmentally restricted 51P1 VH gene. 151 80

SK&F 105685 (N,N-Dimethyl-8,8-dipropyl-2-azaspiro[4.5]decane-2-propanamine+ ++ dihydrochloride) is a novel azaspirane with beneficial activity in animal models of autoimmune diseases such as adjuvant-induced arthritis and experimental autoimmune encephalomyelitis in the Lewis rat and lupus-like disease in the MRL mouse. The effect of SK&F 105685 on the proliferation of rat lymphoid cells was examined in vitro. The compound inhibited the proliferative response of spleen, thymus and lymph node cells to the mitogen concanavalin A (Con A) in a dose-dependent manner but had little or no effect on the mitogenic response of peripheral blood lymphocytes. Although less potent than cyclosporin A, SK&F 105685 was able to inhibit the proliferation of spleen cells stimulated with PMA and ionomycin or the mitogens phytohemagglutinin (PHA), Con A and pokeweed mitogen (PWM). Relatively early event(s) in cell proliferation were affected by SK&F 105685 since delaying addition of the drug by 24 to 48 hours after Con A stimulation of rat spleen cells resulted in reduced levels of suppression. The mode of action of SK&F 105685 appeared to differ from that of cyclosporin A or rapamycin. Unlike cyclosporin A, SK&F 105685 did not affect IL-2 production by Con A-stimulated spleen cells or the IL-2-producing Jurkat cell line, but, like rapamycin, the compound significantly reduced the IL-2-induced proliferation of rat ConA blasts. These results suggest that inhibition of lymphocyte proliferation by SK&F 105685 may require the activity of an intermediate effector cell(s) present in susceptible populations such as cells from the spleen, thymus, lymph nodes and Con A blast preparations but absent or present in low numbers in resistant populations such as peripheral blood cells. Indomethacin and NG-monomethyl-L-arginine (NGMMA), a competitive inhibitor of nitric oxide synthase, were both unable to relieve SK&F 105685-induced suppression of splenic Con A responses thereby ruling out a role for the production of prostaglandins or nitric oxide by macrophages as an intermediate in drug-mediated suppression. In summary, SK&F 105685 was unable to inhibit lymphoproliferative responses by a mechanism distinct from that of cyclosporin A or rapamycin and which appears to involve regulation of cellular interactions rather than a direct effect on responding lymphocytes.
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PMID:Inhibition of lymphoproliferative responses by SK&F 105685, a novel anti-arthritic agent. 166 43

Autoimmune New Zealand white (NZW) mice contribute to (New Zealand black x New Zealand white)F1 mice 1 or more major histocompatibility complex-linked genes that strongly correlate with susceptibility to murine lupus. The NZW class II major histocompatibility complex genes, I-E alpha and I-E beta, were cloned and sequenced and found to differ from normal B10.PL (H-2u) mice by 3 amino acids in the first domain of the I-E beta subunit. Of these differences, the arginine at position 72 of NZW mice could be an important disease determinant since it lies in a predicted antigen-binding cleft.
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PMID:Sequence of I-E genes from autoimmune New Zealand white mice. 210 15

The hyperactivation of B lymphocytes of MRL mice, which are an animal model for human systemic lupus erythematosus (SLE), is characterized as the preferential propagation of gamma + B lymphocytes and IgG overproduction followed by aging. Little is known about the molecular mechanisms, although the involvement of cytokines has been extensively investigated. Here we now show that gamma-committed B lymphocytes selectively exhibit a highly elevated L-citrulline metabolism while mu or alpha-committed B lymphocytes show a normal level in autoimmune MRL mice. L-Arginine proportionally supports the lymphocyte proliferation and antibody production in a concentration-dependent fashion (approximately 100 microM). However, normal murine lymphocytes show an extremely low activity of citrulline metabolism, which converts L-citrulline to L-arginine. Thus, these results suggest that the overexpression of elevated citrulline metabolism is associated with gamma chain expression, and this elevation may enable gamma-committed B lymphocytes to preferentially propagate and overproduce IgG compared with mu or alpha-committed B lymphocytes.
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PMID:Inherited hyperactivation of L-arginine synthesis in gamma + B lymphocytes of systemic autoimmune MRL mice. 212 33

A detailed analysis of variable region sequences, derived from monoclonal lupus anti-DNA autoantibodies has led to several conclusions with respect to the etiology and pathogenesis of systemic lupus erythematosus (SLE). It was found that the gene elements which are expressed in anti-DNA heavy and light chains are present in the germ lines of normal and diseased animals. However, several VH gene segments are not normally expressed in antibodies to external antigens and may, therefore, be excluded by the regulatory mechanism of self-tolerance. The presence of somatic point mutations, which may serve to change antigenic specificity as well as to increase affinity, indicates that an antigen (DNA)-driven mechanism rather than a polyclonal activation is responsible for the autoimmune response in SLE. An additional unique motif of anti-DNA heavy chains was found to consist of an arginine-rich basic peptide in the third complementarity-determining (hypervariable) region. These data have enabled us to build a computer model of the anti-DNA binding site and to design specific inhibitors of the autoimmune reaction.
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PMID:[Genetic origins of anti-DNA autoantibodies]. 236 8

The V region sequences of two anti-DNA (A52, D42) and two anti-RNA (D44, D444) autoantibodies, derived from lupus prone NZB/NZW F1 female mice, were determined by mRNA sequencing. The sequences had the following features: 1) there was no clear sequence relationship between anti-DNA and anti-RNA antibodies; 2) there were no major similarities between any of the L chain sequences and each VL gene segment belonged to a different mouse VK subgroup; 3) the H chains of the two anti-RNA antibodies showed closely related sequences of VH gene segments and very similar third complementarity determining regions (CDR3); 4) the H chains of the two anti-DNA antibodies had VH segments belonging to different VH gene families but had a unique and similar combination of D segments and junctional sequences, suggesting a common recognition element for Ag and/or for idiotypic regulation in the H chain CDR3; and 5) the VH gene segment of one anti-DNA antibody (D42) was found to be very similar to the VH gene segment of a CBA mouse hybridoma antibody (6G6) which binds to the environmental Ag phosphocholine. The three-dimensional structure of the Fv-region of the anti-DNA antibody (D42) was modeled by computer and a stretch of poly(dT), ssDNA was docked to a cleft in the antibody combining site, formed by the three H chain CDR and by CDR1 and CDR3 of the L chain. The cleft is characterized by a preponderance of arginine and tyrosine residues, lining both the walls and base of the cleft.
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PMID:V region sequences of anti-DNA and anti-RNA autoantibodies from NZB/NZW F1 mice. 245 27

Factor B is a centrally important component of the alternative complement pathway. Alternative pathway activation results in factor B cleavage and production of the amino-terminal Ba and the carboxyl-terminal Bb fragments which have molecular weights of approximately 30,000 and 63,000 daltons, respectively. Both Ba and Bb fragments have been reported to express a variety of biological activities in vitro. Thus, binding of Ba and Bb fragments to specific B lymphocyte surface receptors modulates proliferation of prestimulated B cells. In addition, the enzymatically active Bb fragment induces activation and spreading of human and murine macrophages and monocytes as well as regulates C5a des Arg chemotactic activity. The fractional catabolic rate and metabolism of factor B in vivo is similar to that of C3, C4 and C5 complement proteins, which are among the most metabolically active plasma proteins in the circulatory system. Factor B hyperconsumption and increased catabolism, concomitant with factor B fragment production, occurs in a wide variety of diseases, including gram-negative sepsis, autoimmune diseases and burns. Measurement of alternative pathway activation in vivo has been attempted utilized a number of different techniques to quantitate factor B fragments in biological fluids. However, the recent development of enzyme immunoassays (EIA) employing monoclonal antibodies (MoAbs) reactive with factor B fragment neoepitopes provides the best approach currently available for the quantitation of factor B activation fragments. Results obtained using these new MoAb-based EIAs have indicated that factor B fragment concentrations were elevated, as compared with normal donor levels, in EDTA plasma samples obtained from patients with rheumatoid arthritis and systemic lupus erythematosus (SLE). Plasma concentrations of factor B fragments, especially Ba fragment levels, in these patients showed a positive correlation with disease activity scores. One of the highest disease activity correlations was obtained with Ba fragment measurements in SLE plasma samples. In fact, the results strongly suggested that quantitation of Ba fragment levels in SLE plasma samples more accurately reflected disease activity and was a more sensitive predictor of impending flare in these patients than any other test(s) currently available.
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PMID:Ba and Bb fragments of factor B activation: fragment production, biological activities, neoepitope expression and quantitation in clinical samples. 247 21


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