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ID PMID Title PublicationDate abstract
18440104 Amelioration of experimental autoimmune encephalomyelitis by BLyS autovaccine. 2008 Jun 2 The B-lymphocyte stimulator (BLyS) is implicated in various pathophysiological processes. The overexpression of BLyS has been observed in some human diseases, including systemic lupus erythematosus, rheumatoid arthritis, Sjögren's syndrome, and multiple sclerosis. This feature suggests that BLyS may be a therapeutic target for some human autoimmune diseases. We developed a therapeutic vaccine by coupling a tetanus toxoid T-helper cell epitope with the C-terminal of BLyS (TT-BLyS). This vaccine can induce high titers of neutralizing antibodies against BLyS in an animal model; the antibody has markedly protective effects on experimental autoimmune encephalomyelitis in rats, which is induced by inoculation of spinal cord homogenate. Our data suggest that the BLyS autovaccine may be a useful candidate for the treatment of some autoimmune diseases associated with the production of BLyS.
18223103 Stimulated T cells generate microparticles, which mimic cellular contact activation of hum 2008 Apr Imbalance in cytokine homeostasis plays an important part in the pathogenesis of chronic inflammatory diseases such as multiple sclerosis and rheumatoid arthritis. We demonstrated that T cells might exert a pathological effect through direct cellular contact with human monocytes/macrophages, inducing a massive up-regulation of the prototypical proinflammatory cytokines IL-1beta and TNF. This mechanism that might be implicated in chronic inflammation is specifically inhibited by high-density lipoproteins (HDL). Like many other stimuli, besides proinflammatory cytokines, the contact-mediated activation of monocytes induces the production of cytokine inhibitors such as the secreted form of the IL-1 receptor antagonist (sIL-1Ra). The present study demonstrates that stimulated T cells generate microparticles (MP) that induce the production of TNF, IL-1beta, and sIL-1Ra in human monocytes; the production of TNF and IL-1beta but not that of sIL-1Ra is inhibited in the presence of HDL. The results were similar when monocytes were stimulated by whole membranes of T cells or soluble extracts of the latter. This suggests that MP carry similar monocyte-activating factors to cells from which they originate. Thus, by releasing MP, T cells might convey surface molecules similar to those involved in the activation of monocytes by cellular contact. By extension, MP might affect the activity of cells, which are usually not in direct contact with T cells at the inflammatory site. Furthermore, this study demonstrates that HDL exert an anti-inflammatory effect in nonseptic activation of human monocytes, not only by inhibiting the production of IL-1beta and TNF but also, by leaving sIL-1Ra production unchanged.
18208821 Association of autoantibodies with Ku and DNA repair proteins in connective tissue disease 2008 Feb OBJECTIVE: To analyse the autoimmune response to DNA damage response factors in systemic autoimmune rheumatic disease (SARD) patients and to determine their association with autoantibodies to Ku antigen. METHODS: We have screened the serum of 239 patients suffering from SARD, including systemic lupus erythematosus, systemic sclerosis and rheumatoid arthritis to detect the occurrence of autoantibodies to Ku and four other DNA damage response factors that form macromolecular complexes with Ku using an immunoprecipitation assay. RESULTS: We identified samples positive for autoantibodies to Ku (20.5%), DNA-dependent protein kinase catalytic subunit (DNA-PKcs, 8.4%) and poly(ADP-ribose) polymerase (5.9%), and report for the first time autoantibodies directed against two additional DNA repair proteins, Werner (6.3%) and Mre11 (9.6%). Remarkably, we found a striking correlation between the production of antibodies to Ku and the other four Ku-binding factors. Sixty-five percent of anti-Ku-positive sera were found to contain at least one of the four anti-DNA repair antibodies vs only 10% of the anti-Ku-negative sera. CONCLUSION: Our results suggest that the autoantibodies directed against Ku are elicited by macromolecular protein complexes containing Ku and the associated DNA damage proteins. The presence of autoantibodies directed against macromolecular complexes known to play roles in the DNA damage response provides evidence that B-cell responses to latent or persistent DNA damage may be present at the onset or during the development of autoimmunity in certain SARDs.
18177457 IgG oligosaccharide alterations are a novel diagnostic marker for disease activity and the 2008 May BACKGROUND AND AIMS: Patients with inflammatory bowel disease (IBD) share several immunologic similarities with rheumatoid arthritis (RA). Patients with RA have significantly increased levels of serum agalactosyl immunoglobulin G (IgG). Our aim was to investigate the clinical significance of analyzing the oligosaccharide structure of serum IgG in patients with IBD. METHODS: Serum IgG oligosaccharide structures were analyzed using high-performance liquid chromatography in 60 patients with Crohn's disease (CD), 58 patients with ulcerative colitis (UC), 27 healthy volunteers (HV), and 15 disease controls (DC). The activity and mRNA level of beta-1,4-galactosyltransferase (Beta4GalT) in antibody-secreting cells were investigated in these subjects. RESULTS: The agalactosyl fraction of the fucosylated IgG oligosaccharides (G0F/G2F) in CD and UC was significantly greater than that in HV and DC (P < 0.001). The percentage of subjects with a high G0F/G2F in CD, UC, HV, and DC was 72%, 33%, 0%, and 0%, respectively. G0F/G2F, which is significantly correlated with disease severity in both CD and UC, had higher sensitivity to diagnose IBD compared with anti-Saccharomyces cerevisiae antibody. Moreover, G0F/G2F was significantly correlated with the prognosis of UC patients: patients with a high G0F/G2F did not maintain long-term remission. The activity and mRNA level of Beta4GalT were significantly elevated in UC but not in CD. CONCLUSIONS: G0F/G2F is a potentially effective diagnostic marker of disease activity in both CD and UC, and of the clinical course in UC. A pathophysiologic difference between CD and UC was also demonstrated.
17998807 Rationale for the use of histone deacetylase inhibitors as a dual therapeutic modality in 2006 Apr Major recent advances in the field of chromatin remodeling have dramatically changed our understanding of the ways in which genes are regulated. Epigenetic regulators such as histone deacetylases (HDACs) and histone acetyltransferases (HATs) are increasingly being implicated as direct or indirect components in the regulation of expression of neuronal, immune and other tissue specific genes. HDACs and HATs have been shown to play important roles in cell growth, cell cycle control, development, differentiation and survival. Mutations in genes that encode HDAC-binding proteins cause neurological disorders, such as MeCP2 mutations in Rett's syndrome. Mutations of CBP, a gene with HAT function, cause the mental retardation-associated Rubinstein-Taybi syndrome. Recently, HDAC inhibitors have been found to ameliorate progression of the spinal muscular atrophy (SMA) motor neuron disease and the Huntington disease mouse models. The neuroprotective role of HDAC inhibitors seems to extend to other diseases that share mechanisms of oxidative stress, inflammation and neuronal cell apoptosis. HDAC inhibitors also have widespread modulatory effects on gene expression within the immune system and have been used successfully in the lupus and rheumatoid arthritis autoimmune disease models. Recently, we demonstrated the efficacy of the HDAC inhibitor Trichostatin A in ameliorating disease in the multiple sclerosis (MS) animal model, experimental autoimmune encephalomyelitis (EAE). In this review we describe the current literature surrounding these inhibitors and propose a rationale for harnessing both their neuroprotective and anti-inflammatory effects to treat MS, an autoimmune, demyelinating and degenerative disease of the human central nervous system (CNS).
17996896 Comparative analyses of complex formation and binding sites between human tumor necrosis f 2007 Dec 14 Tumor necrosis factor-alpha (TNFalpha)-blocking therapy, using biologic TNFalpha antagonists, has been approved for the treatment of several diseases including rheumatoid arthritis, psoriasis and Crohn's disease. There have been few detailed studies of binding characterizations for the complex formation by TNFalpha and clinically relevant antagonists, particularly Infliximab (Remicade) and Etanercept (Enbrel). Here we characterized the binding stoichiometry and size of soluble TNFalpha-antagonist complexes and identified energetically important binding sites on TNFalpha for the three antagonists, Etanercept, Infliximab, and the recently developed humanized TNFalpha neutralizing monoclonal antibody, YHB1411-2. Size-exclusion chromatography and dynamic light scattering analyses revealed that the three antagonists formed distinct thermodynamically stable TNFalpha-antagonist complexes that exhibited differences in their size and composition. Energetically important binding residues on TNFalpha were identified for each antagonist by a sequence of experiments that consisted of competition binding assays, fragmentations, loop mutations, and single-point mutations using yeast surface-displayed TNFalpha, which was further confirmed for solubly purified TNFalpha mutants by surface plasmon resonance technique. Analyses of the binding geometry based on binding site location, spatial constraints, and valency satisfaction allowed us to interpret the thermodynamically stable complexes as follows: one molecule of Etanercept and one molecule of trimeric TNFalpha (Etanercept1-TNFalpha1), Infliximab6-TNFalpha3, and YHB1411-2(4)-TNFalpha2. The distinct features of the soluble antagonist-TNFalpha complex formation among the antagonists may give further insights into their different neutralizing mechanisms and pharmacokinetic profiles.
17986481 Hospitalizations and mortality in systemic sclerosis: results from the Nationwide Inpatien 2007 Dec OBJECTIVE: To study the causes of hospitalizations and predictors of subsequent adverse outcomes for contemporary cohorts of patients with systemic sclerosis (SSc) in the USA. METHODS: The data source was the 2002 and 2003 Healthcare Cost and Utilization Project-Nationwide Inpatient Sample (HCUP-NIS) databases. We identified all discharges with an International Classification of Diseases-Clinical Modification (ICD9-CM) code of 710.1 (limited and diffuse SSc), then excluded those with concomitant diagnoses for lupus or rheumatoid arthritis. We calculated hospitalization rates, in-hospital mortality rates and mean length of stay (LOS). Multivariate logistic and linear regression models for in-hospital death and LOS were performed adjusting for sociodemographic and comorbidity covariates. RESULTS: The overall in-hospital mortality rate was 6.3% and the mean LOS was 6.6 days. Hospitalization rates were 4.5 times higher in women than in men, but in-hospital mortality was approximately 25% lower (P = 0.005). SSc was the most common principal diagnosis for all SSc hospitalizations, with the most common secondary diagnosis (24%) being pulmonary fibrosis. After SSc, respiratory failure was the second most common principal diagnosis in patients who died. Pulmonary fibrosis increased the odds of in-hospital death by 2.63 [95% confidence interval (CI) 1.98-3.49] fold and increased LOS by 7.25% (95% CI 0.90-13.60). CONCLUSIONS: Women with SSc had higher rates of hospitalization but lower in-hospital mortality than men. Pulmonary fibrosis was the major predictor of poor hospitalization outcomes in SSc patients in recent years, emphasizing the importance of continuing to develop more effective therapies for this fatal complication of the disease.
17925397 IRF3-dependent type I interferon response in B cells regulates CpG-mediated antibody produ 2008 Jan 11 Hypomethylated CpG oligonucleotides (CpG) are not only potent adjuvants for enhancing adaptive immune responses but may also play a critical role in the development of autoimmune diseases such as Rheumatoid Arthritis (RA) and Systemic Lupus Erythematosus (SLE). Here we provide evidence that, in addition to dendritic cells, murine B lymphocytes also exhibit a type I IFN response to CpG-B. Unlike dendritic cells, B cell-mediated type I IFN induction depended on the transcription factor IRF3, but similar to dendritic cells this pathway was independent of the IRF3 kinase TBK1. Utilizing type I IFN receptor-deficient mice, we were able to demonstrate that this IFN pathway enhanced Syndecan-1 expression and IgM production and was required for IgG2a production following CpG-B stimulation. Overall, our findings identify a unique IFN pathway in B cells that may play a central role in mediating B cell biology in response to CpG, potentially implicating this pathway in autoantibody production and the pathogenesis of certain autoimmune diseases.
17724644 [BIAX total wrist arthroplasty: management and results after 42 patients]. 2007 Aug The BIAX total wrist arthroplasty was introduced in 1983 by Cooney, Beckenbaugh and Linscheid in the USA. However the production of this prosthesis was discontinued in 2004 without having developed a follow-up model. Between 2001 and 2003 we have implanted the BIAX prosthesis in 42 cases. In contrast to other studies, our patients had more post-traumatic (n = 19) and degenerative athroses (n = 20), only 3 patients had rheumatoid arthritis of the wrist. Follow-up time was 2.6 (+/- 0.8) years. The patients were 53 (+/- 11) years old. Indication for total wrist arthroplasty was comparable to that for arthrodesis. However, as pain reduction is lower in heavy workers these patients were excluded from arthroplasty implantation. Range of movement was preserved by total arthroplasty or slightly improved. Pain was reduced by 4.5 (+/- 2.3) points from 7.6 (+/- 1.0) to 3.0 (+/- 2.1) using a visual analogue scale with 0 points for no pain and 10 points for severe pain. Patient satisfaction with the operation was 7.7 (+/- 2.2, 1 bad, 10 excellent). 4 patients had a postoperative dislocation. After reposition the joints were permanently stable. In one case a flexion contracture of unknown origin was treated by tendon transfer. In 11 patients the prosthesis had to be removed after 2 (+/- 0.9) years. Four of these patients received an arthrodesis, 7 had a change to the Universal2 prosthesis. The reason for explantation was mainly abrasion of the dorsal polyethylene edge of the proximal socket, resulting in foreign body reaction, synovialitis and loosening of the prostheses in 7 patients and permanent dislocation in 2 patients due to the then flattened socket. These complications led us to abandon the implantation of the BIAX prostheses.
17672076 [Factors affecting efficacy of proton pump inhibitors in NAID-induced gastric ulcers]. 2007 AIM: To determine factors which may influence efficacy of therapy with proton pump inhibitors (PPI) in gastric ulcer (GU) induced by nonsteroid anti-inflammatory drugs (NAID). MATERIAL AND METHODS: Two groups of GU patients treated with PPI in 2001-2005 were identified: 41 cases when ulcer healing was not achieved for 3 weeks and more (study group) and 218 cases treated for this time successfully (controls). The groups did not differ significantly by gender (females 84.6 and 78.6%) and age (59.2 +/- 16.8 and 58.7 +/- 12.4 years). RESULTS: The patients of the study group had ulcers of 10 mm and more in size much more frequently than the controls (OR 12.5, CI 5.8-26). Also, rheumatoid arthritis (RA), ulcer history, intake of glucocorticosteroids, cytotoxic drugs, ineffective preventive treatment with PPI (OR 5.3, CI 3.4-8.4; OR 3.1, CI 1.5-6.0; OR 3.1, CI 1.6-6.0; OR 3.4, CI 1.7-6.7; OR 2.7, CI 1.3-5.6, respectively) were recorded in the study group more often. Helicobacter pylori was absent in 75.6% patients of the study group but these findings can not be compared with those in the controls as the majority of them had not been examined for gastric H. pylori. CONCLUSION: Large ulcer, RA, ulcer history, treatment with GCS, cytotoxic drugs, PPI and, probably, the absence of H. pylori decrease efficacy of PPI in gastric ulcer induced by NAID.
17574655 Effects of neridronic acid on osteoclasts derived by physiological dual-cell cultures. 2007 Increased osteoclastic activity is observed in many osteopathic disorders - including postmenopausal osteoporosis, Paget's disease, primary bone tumours, lytic bone metastases, multiple myeloma and rheumatoid arthritis - that involve increased bone resorption and a loss of bone mass. Bisphosphonates are highly effective inhibitors of bone resorption that selectively affect the osteoclasts. The aim of this study was to obtain more information about the mechanism of action of bisphosphonates such as neridronic acid using a dual-cell culture model. As a model of osteoclastogenesis we used a murine monocyte/macrophage cell line RAW 264.7 type CRL 2278 co-cultured with murine osteoblasts. The monocyte-osteoblast system allows physiological experimentation of bone anti-resorption drugs, simulating bone turnover in pathologies such as osteoporosis. The direct actions of neridronic acid on cell proliferation and functionality in the co-culture model were examined using tartrate-resistant acid phosphatase (TRAP) assay, immunohistochemical localization of actin, and transmission and scanning electron microscopy (SEM). Results showed that the percentage of TRAP-positive cells, an early marker of osteoclastic differentiation, was significantly higher in control cultures than in co-cultures treated with variable concentrations of neridronic acid. Neridronic acid induced dramatic morphological changes, characterized by the loss of the ruffled border. The actin ring associated with the plasma membrane of the cells treated with neridronic acid was shown to break down. The tissue-specific targeting of neridronic acid to bone mineral suggests that it may inhibit bone resorption by direct effects on osteoclasts or other bone cells in the immediate microenvironment of the osteoclasts. From our study, we conclude that structural alterations induced by neridronic acid in our co-culture system lead to decreased osteoclast function. This may encourage the use of neridronic acid to reduce bone resorption in the therapy of demineralizing metabolic bone disorders.
17542999 Has the use of disease-modifying anti-rheumatic drugs changed as a consequence of controll 2007 Sep BACKGROUND: A prerequisite for access to biological agents for the treatment of rheumatoid arthritis under Australia's Pharmaceutical Benefits Scheme (PBS) is evidence of an adequate trial of conventional disease-modifying anti-rheumatic drugs (DMARDs). The aim of this study was to examine whether there were changes in prescribing DMARDs since the introduction of the PBS criteria for access to biologicals in August 2003. METHODS: A retrospective study was undertaken of the national use of DMARDs in the period before and after the introduction of biologicals under the PBS. Dispensing data were analysed for changes in patterns of DMARD prescription rates (2000-2005). RESULTS: There were 2 887 746 prescriptions for DMARDs between August 2000 and June 2005. PBS prescriptions accounted for 95% of these. Government expenditure for the DMARDs was $A156m. Trends in the use of DMARDs remained relatively steady over the study period without a significant change around the time the PBS criteria for biologicals were introduced. Use of hydroxychloroquine and leflunomide increased steadily, use of methotrexate and sulfasalazine was stable and use of gold preparations and penicillamine was considerably lower during this 5-year period. CONCLUSION: Introduction of PBS criteria for access to biologicals did not alter the trends in use of DMARDs based on national dispensing data. This study emphasized the value that would accrue from availability of more comprehensive, de-identified, individual patient data that would enable more detailed examination of the use of medicines. These data are available, but cannot be easily accessed. It is time to make the data available for approved, ethical research in the interests of better outcomes from medicines supplied under PBS.
17225465 Effects of mizoribine on MHC-restricted exogenous antigen presentation in dendritic cells. 2006 Dec Mizoribine (MZR) has been shown to possess immunosuppressive activity that selectively inhibits the proliferation of lymphocytes by interfering with inosine monophosphate dehydrogenase. The efficacy of MZR is not only in patients who have had renal transplantation, but also in patients with rheumatoid arthritis (RA), lupus nephritis, and primary nephritic syndrome. Because the exact mechanism of its immunosuppressive action is not clear, the object of this study was to examine the ability of MZR to regulate the antigen presenting cells (APCs), dendritic cells (DCs). In this work, we tested whether MZR (1-10 microg/mL) could inhibit the cross-presentation of DCs. DC2.4 cells (H-2K(b)) or bone marrow-derived DCs (BM-DCs) generated from BM cells of C57BL/6 mouse (H-2K(b)) were cultured in the presence of MZR with OVA-microspheres, and the amount of OVA peptide-class I MHC complexes was measured by a T cell hybridoma, B3Z, that recognizes OVA (257-264 : SIINFEKL)-H-2Kb complex and expresses-galactosidase. MZR profoundly inhibited the expression of SIINFEKL-H-2K(b) complexes. This inhibitory activity of MZR appeared to affect the phagocytic activity of DCs. MZR also decreased IL-2 production when we examined the effects of MZR on CD4+ T cells. These results provide an understanding of the mechanism of immunosuppressive activity of MZR on the inhibition of MHC-restricted antigen presentation and phagocytic activity in relation to their actions on APCs.
17207380 Incidence and clinical features of cytomegalovirus infection diagnosed by cytomegalovirus 2006 Nov OBJECTIVE: To investigate the incidence and clinical features in patients with cytomegalovirus (CMV)-positive antigenemia during high dose corticosteroid therapy for collagen vascular diseases, and risk factors associated with it. PATIENTS AND METHODS: We examined retrospectively 35 consecutive patients for the presence of CMV-positive pp65 antigenemia. The patients were admitted to Saka General Hospital from 2000 to 2003, and were administered more than 0.5 mg/kg of body weight/day of peroral prednisolone for collagen vascular diseases. Characteristics of patients with and without CMV-positive antigenemia were compared. RESULTS: CMV-positive antigenemia was detected in 14 patients (40.0%), including six with microscopic polyangitis, three with rheumatoid arthritis, and five with other conditions. Three patients (8.6%) were diagnosed as having a CMV disease: pneumonitis or encephalitis. Symptoms and laboratory findings, including slight fever and a low increase in levels of hepatic enzymes and cytopenia, were observed in 10 of the 14 patients. Two patients died of CMV diseases refractory to ganciclovir. Ages of more than 70 years old were associated with the presence of CMV-positive antigenemia (relative risk = 4.5, 95% confidence interval = 1.14-17.6). CONCLUSION: CMV infection diagnosed by CMV pp65 antigenemia assay is not rare during high dose corticosteroid therapy for collagen vascular diseases, and advanced age is considered a risk factor for it. It has a variety of symptoms and laboratory findings, which are mild and nonspecific to this type of infection, and they may not be clearly noted as clinical signs of CMV infection, even in patients with CMV diseases whose prognoses can be unsatisfactory. During high dose corticosteroid therapy for collagen vascular diseases, careful attention should be paid to CMV infection.
17185762 Pyrosequencing-based strategies for improved allele typing of human leukocyte antigen loci 2007 Successful transplantation of tissue during solid organ and bone marrow transplantation relies on accurate determination of the human leukocyte antigen (HLA) phenotype of the potential donor(s) and recipient. Matching donor with recipient for a kidney transplant generally means finding a six-antigen match by looking at each of two alleles at HLA-A, -B, and -DR loci. For bone marrow transplantation the HLA-C and -DQ alleles are also considered. Molecular techniques, including sequencing, are capable of precisely defining HLA alleles. Because of the large number of possible allelic combinations there are numerous ambiguities associated with heterozygous genotypes even when sequence-based typing protocols are used. Sequencing-by-synthesis methodology employed by Pyrosequencing represents an improvement when applied to HLA genotyping that allows resolution of many ambiguous allelic pairs. Out-of-phase sequencing of HLA alleles by Pyrosequencing can resolve cis/trans ambiguities that would otherwise require the sequencing of isolated cloned DNAs. Single-nucleotide polymorphism typing of HLA for the presence of specific variants is also beneficial for monitoring HLA-encoded genetic risk to autoimmune diseases, such as celiac disease, rheumatoid arthritis, and type 1 diabetes mellitus.
17067557 Melittin inhibits inflammatory target gene expression and mediator generation via interact 2007 Jan 15 We previously found that bee venom (BV) and melittin (a major component of BV) has anti-inflammatory effect by reacting with the sulfhydryl group of p50 of NF-kappaB. Since the sulfhydryl group is present in IkappaB kinase (IKKalpha and IKKbeta), anti-inflammatory effect of melittin via interaction with IKKs was investigated. We first examined binding of melittin to IKKs using surface plasmon resonance analyzer. Melittin binds to IKKalpha (K(d) = 1.34 x 10(-9) M) and IKKbeta (K(d) = 1.01 x 10(-9) M). Consistent with the high binding affinity, melittin (5 and 10 microg/ml) and BV (0.5, 1 and 5 microg/ml) suppressed sodium nitroprusside, TNF-alpha and LPS induced-IKKbeta and IKKbeta activities, IkappaB release, and NF-kappaB activity as well as the expressions of iNOS and COX-2, and the generation of nitric oxide (NO) and prostaglandin E(2) (PGE(2)) in Raw 264.7 mouse macrophages and synoviocytes obtained from rheumatoid arthritis patients. The binding affinities of melittin to mutant IKKs, was reduced, and the inhibitory effect of melittin on IKK and NF-kappaB activities, and NO and PGE(2) generation were abrogated by the reducing agents or in Raw 264.7 transfected with mutant plasmid IKKalpha (C178A) or IKKbeta (C179A). These results suggest that melittin binding to the sulfhydryl group of IKKs resulted in reduced IKK activities, IkappaB release, NF-kappaB activity and generation of inflammatory mediators, indicating that IKKs may be also anti-inflammatory targets of BV.
16966257 The influence of pregnancy on the development of autoimmunity in chronic lymphocytic leuke 2006 Aug To examine whether pregnancy influences the development of autoimmunity in chronic lymphocytic leukemia (CLL), we studied 591 consecutive CLL patients (202 post-menopausal women and 389 men). The mean observation time for all patients was 3.8 years, corresponding to approximately 2200 person-years of follow-up. Autoimmune manifestations were analyzed in 194 women with known obstetric history and known number of long-term sexual partners, and in the 389 male CLL patients for comparison. One hundred and fifty-nine of the CLL patients exhibited autoimmune manifestations, 38% in females and 21% in men. In female CLL patients, the frequency of autoimmunity and the number of pregnancies and the number of partners were strongly correlated. Each of the major autoimmune types approximately doubled in frequency for each additional pregnancy. The impact of pregnancy on expressed autoimmunity increased with each additional sexual partner (the odds of autoimmunity increased 11 times with each long-term sexual partner). The average numbers of pregnancies in female CLL patients with and without autoimmunity were 4.92 and 2.24, respectively (P < 0.001). Coombs' positive autoimmune anemia, a gastric ulcer with parietal cell autoantibodies and idiopathic thrombocytopenic purpura were equally common in women and men, whereas autoimmune thyroiditis, Sjögren's syndrome, rheumatoid arthritis and systemic lupus erythematosus were seen in higher rates in women than in men. The spectrum of autoimmunity suggests that pregnancy-related alloimmunization may be involved in the development of autoimmunity in CLL.
16948641 Humanized transgenic mice expressing HLA DR4-DQ3 haplotype: reconstitution of phenotype an 2006 Sep Many autoimmune conditions have close genetic linkages to particular human histocompatibility leukocyte antigen (HLA) class II genes. With the aim of establishing a murine model of autoimmune disease, we have generated an HLA DR4-DQ3 haplotype transgenic (Tg) mouse that expresses a 440-kb yeast artificial chromosome harbouring DRA, DRB1*040101, DRB4*010301, DQA1*030101, DQB1*0302 and all the internal regulatory segments. This Tg mouse line was crossed to human CD4 (hCD4) Tg mice and endogenous class II knockout mice (I-A(o/o) and I-E(o/o)) lines to generate a DR4-DQ3.hCD4.IAE(o/o) Tg line. The Tg DR and DQ molecules are expressed on the physiological cell types in these animals, i.e. on most B cells (>85%), dendritic cells (DCs) and macrophages but not on T cells, with levels of expression comparable with those of human B cells (where DR > DQ expression). The DR4/DQ3 transgenes fully reconstituted the CD4 T-cell compartment, in both the thymus and the periphery, and the analysis of the T-cell receptor repertoire in the Tg mice confirmed that these class II molecules were able to mediate thymic selection of a broad range of Vbeta families. HLA DR4- and DQ3-restricted T-cell responses were elicited following immunization with known T-cell determinants presented by these molecules. Furthermore, the DR4-DQ3-restricted CD4(+) T cells conferred protective antibody-mediated immunity against an otherwise lethal infection with Salmonella enterica var. typhimurium. These new DR4-DQ3 Tg mice should prove to be valuable tools for dissecting the importance of this class II haplotype in autoimmune disorders like rheumatoid arthritis.
16391555 Evaluating the role of the 620W allele of protein tyrosine phosphatase PTPN22 in Crohn's d 2006 Mar The 620W allele of PTPN22 has been associated with susceptibility to several different forms of chronic inflammatory disease, including Type 1 diabetes (T1D), rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), and autoimmune thyroiditis (AIT). We set out to explore its possible role in two other inflammatory diseases: multiple sclerosis (MS) and Crohn's disease (CD). In our cohort of 496 MS trios from the United Kingdom, we observed reduced transmission of the PTPN22 620W allele. The CD sample consisted of 169 trios as well as 249 cases of CD with their 207 matched control subjects collected in the province of Québec, Canada; there was also no evidence of association between the PTPN22 620W allele and susceptibility for CD. Pooled analyses combining our data with published data assessed a total of 1496 cases of MS and 1019 cases of CD but demonstrated no evidence of association with either disease. Given the modest odds ratios of known risk alleles for inflammatory diseases, these analyses do not exclude a role for the PTPN22 allele in susceptibility to CD or MS, but they do suggest that such a putative role would probably be more modest than that reported so far in T1D, RA, SLE, and AIT.
16336962 Signal transduction by VEGF receptors in regulation of angiogenesis and lymphangiogenesis. 2006 Mar 10 The VEGF/VPF (vascular endothelial growth factor/vascular permeability factor) ligands and receptors are crucial regulators of vasculogenesis, angiogenesis, lymphangiogenesis and vascular permeability in vertebrates. VEGF-A, the prototype VEGF ligand, binds and activates two tyrosine kinase receptors: VEGFR1 (Flt-1) and VEGFR2 (KDR/Flk-1). VEGFR1, which occurs in transmembrane and soluble forms, negatively regulates vasculogenesis and angiogenesis during early embryogenesis, but it also acts as a positive regulator of angiogenesis and inflammatory responses, playing a role in several human diseases such as rheumatoid arthritis and cancer. The soluble VEGFR1 is overexpressed in placenta in preeclampsia patients. VEGFR2 has critical functions in physiological and pathological angiogenesis through distinct signal transduction pathways regulating proliferation and migration of endothelial cells. VEGFR3, a receptor for the lymphatic growth factors VEGF-C and VEGF-D, but not for VEGF-A, regulates vascular and lymphatic endothelial cell function during embryogenesis. Loss-of-function variants of VEGFR3 have been identified in lymphedema. Formation of tumor lymphatics may be stimulated by tumor-produced VEGF-C, allowing increased spread of tumor metastases through the lymphatics. Mapping the signaling system of these important receptors may provide the knowledge necessary to suppress specific signaling pathways in major human diseases.