Relationship and significance between anti-b2-glycoproteinⅠantibodies and platelet activation state in patients with ulcerative colitis

AIM： To study the relationship between anti-β2- glycoprotein Ⅰ （aβ2GPⅠ） antibodies and platelet activation state in patients with ulcerative colitis （UC） and its significance. METHODS： Peripheral blood samples were collected from 56 UC patients （34 males and 22 females, aged 43.5 years, range 21-66 years）, including 36 at active stage and 20 at remission stage, and 25 sex-and age-matched controls. The level of aβ2GP Ⅰ was measured by ELISA. The platelet activation markers, platelet activation complex- Ⅰ （PAC- Ⅰ ） and P-selectin （CD62P） were detected by flow cytometry. RESULTS： The A value for IgG aβ2GP Ⅰ in the active UC group was 0.61 ± 0.13, significantly higher than that in the remittent UC and control groups （0.50 ± 0.13 and 0.22 ± 0.14, P 〈 0.01）. There was a significant difference between the two groups （P 〈 0.01）. The A value for IgM aβ2GP Ⅰ in the active and remittent UC groups was 0.43 ± 0.13 and 0.38 ± 0.12, significantly higher than that in the control group （0.20 ± 0.12, P 〈 0.01）. However, there was no significant difference between the two groups （P 〉 0.05）. The PAC- Ⅰ positive rate for the active and remittent UC groups was 30.6% ± 7.6% and 19.6% ± 7.8% respectively, significantly higher than that for the control group （6.3% ± 1.7%,P 〈 0.01）. There was a significant difference between the two groups （P 〈 0.01）. The CD62P positive rate for the active and remittent UC groups was 45.0% ± 8.8% and 31.9% ± 7.8% respectively, significantly higher than that for the control group （9.2% ± 2.7%, P 〈 0.01）. There was a significant difference between the two groups （P 〈 0.01）. In the active UC group, the more severe the state of illness was, the higher the A value for IgG aβ2GP Ⅰ was, and the positive rate for PAC-Ⅰ and CD62P was positively correlated with the state of illness （Faβ2GP Ⅰ = 3.679, P 〈 0.05; FPAC-Ⅰ （%） = 5.346, P 〈 0.01; and FCD62P （%） = 5. 418, P 〈 0.01）. Meanwhile, in the same state of illness, the A value for IgG aβ2GP Ⅰ was positively correlated to the positive rates for PAC-Ⅰ and CD62P. CONCLUSION： aβ2GP Ⅰ level, platelet activation state and their relationship of them are closely correlated with the pathogenesis and development of UC.

Prevalence of Anti-Cardiolipin and Anti-β2 Glycoprotein Antibodies in Indian Systemic Lupus Erythematosus Patients

Anti-phospholipid antibodies (APA) like anti-cardiolipin antibodies (ACA) and anti-β2glycoprotien (anti-β2GP) are important cause of venous and arterial thrombosis and other occlusive vascular diseases. The prevalence of these antibodies in SLE patients at the time of diagnosis is not known in Indian SLE patients. This study was conducted to evaluate the prevalence of ACA and anti-β2GP autoantibodies in SLE patients and to correlate them with disease activity and immune parameters such as C3, C4 and CRP levels. where 85 SLE patients referred from Rheumatology Department, KEM hospital, Mumbai were studied. SLE disease activity was evaluated by SLE Disease Activity Index (SLEDAI) score at the time of evaluation. All patients studied were in an active stage of disease of which 37.6% patients had renal disorders, which were categorized as Lupus Nephritis (LN) and 62.3% patients did not show any renal manifestations (non-LN). ACA and anti-β2GP autoantibodies, to IgG and IgM subclasses were tested by ELISA. C3, C4 and CRP levels were detected by nephelometer. It was observed that 12.9% patients were IgG-ACA and IgM-ACA positive and ACA positivity was noted more among LN group Anti-β2GP autoantibody positivity was 27.1% for IgG and 31.8% for IgM., IgG-anti-β2GP antibodies were slightly higher in non-LN patients, whereas a higher incidence of IgM-anti-β2GP antibodies were detected in LN patients. Hence detection both ACA and anti-β2GP antibodies along with associated immune parameters were helpful to evaluate their possible association with disease severity in SLE patients. A long term follow up of patients having ACA and anti-β2GP antibodies without thrombotic event is also needed to detect their possible thrombotic event in future along with their clinical presentation.

Periodontitis and Inflammation: Plasma High Titer Naturally Occurring Anti-Glucan Antibodies Form Immune Complex with Streptococcus mutans Antigen

Atheromatous plaques usually contain antigens of the periodontitis-causing bacteria Streptococcus mutans though molecular mechanism of this incorporation remains unknown. Since vascular adhesion and inflammatory potential of Immune Complexes (IC) are known we investigated the naturally occurring plasma antibodies that recognize major antigens from S. mutans. S. mutans-binding plasma proteins (SMBP) prepared by affinity chromatography on a column of heat-killed S. mutans could recognize α- and β-linked glucose in dextran and yeast respectively but not galactose in glycoproteins. SMBP contained only three proteins, each corresponding in electrophoretic mobility to standard plasma IgG, IgA or IgM. The major positively and negatively charged protein antigens (PSMAg and NSMAg) isolated from S. mutans by electrophoresis and ion exchange chromatography respectively were recognized sugar-reversibly by the anti-β-glucan antibody (ABG) and though less avidly, by the dextran-binding immunoglobulin (DIg) in normal plasma. NSMAg addition resulted in near doubling of IC-bound immunoglobulins in immunoglobulin-rich fraction of plasma. IC isolated from above fraction after NSMAg addition had substantially more IgA and IgM content than total plasma immunoglobulins. IC formation by NSMAg was significantly inhibited by ABG- and DIg-specific sugars or by selective withdrawal of ABG or DIg from plasma. ABG and DIg being relatively high titer plasma antibodies IC formation with them suggested a possible route for vascular adhesion and damage by S. mutans and its antigens. Further, high IgA content of these ICs indicated their susceptibility to tissue uptake through cell surface galectin-1 for which IgA is the lone immunoglobulin ligand.

Prevalence, significance and predictive value of antiphospholipid antibodies in Crohn's disease

AIM: To assess the prevalence and stability of different antiphospholipid antibodies(APLAs) and their association with disease phenotype and progression in inflammatory bowel diseases(IBD) patients.METHODS: About 458 consecutive patients [Crohn's disease(CD): 271 and ulcerative colitis(UC): 187] were enrolled into a follow-up cohort study in a tertiary IBD referral center in Hungary. Detailed clinical phenotypes were determined at enrollment by reviewing the patients' medical charts. Disease activity, medical treatment and data about evolvement of complications or surgical interventions were determined prospectively during the follow-up. Disease course(development f complicated disease phenotype and need for surgery),occurrence of thrombotic events, actual state of diseaseactivity according to clinical, laboratory and endoscopic scores and accurate treatment regime were recorded during the follow-up,(median, 57.4 and 61.6 mo for CD and UC). Sera of IBD patients and 103 healthy controls(HC) were tested on individual anti-β2-Glycoprotein-I(anti-β2-GPI IgA/M/G), anti-cardiolipin(ACA IgA/M/G)and anti-phosphatidylserine/prothrombin(anti-PS/PT IgA/M/G) antibodies and also anti-Saccharomyces cerevisiae antibodies(ASCA IgA/G) by enzyme-linked immunosorbent assay(ELISA). In a subgroup of CD(n = 198) and UC patients(n = 103), obtaining consecutive samples over various arbitrary timepoints during the disease course, we evaluated the intraindividual stability of the APLA status. Additionally,we provide an overview of studies, performed so far, in which significance of APLAs in IBD were assessed.RESULTS: Patients with CD had significantly higher prevalence of both ACA(23.4%) and anti-PS/PT(20.4%) antibodies than UC(4.8%, p < 0.0001 and10.2%, p = 0.004) and HC(2.9%, p < 0.0001 and15.5%, p = NS). No difference was found for the prevalence of anti-β2-GPI between different groups(7.2%-9.7%). In CD, no association was found between APLA and ASCA status of the patients.Occurrence of anti-β2-GPI, ACA and anti-PS/PT was not different between the group of patients with active vs inactive disease state according to appropriate clinical, laboratory and endoscopic scores in CD as well as in UC patients. All subtypes of anti-β2-GPI and ACA IgM status were found to be very stable over time, in contrast ACA IgG and even more ACA IgA status showed significant intraindividual changes.Changes in antibody status were more remarkable in CD than UC(ACA IgA: 49.9% vs 23.3% and ACA IgG:21.2% vs 5.8%). Interestingly, 59.1% and 30.1% of CD patients who received anti-TNF therapy showed significant negative to positive changes in ACA IgA and IgG antibody status respectively. APLA status was not associated with the clinical phenotype at diagnosis or during follow-up, medical therapy, or thrombotic events and it was not associated with the probability of developing complicated disease phenotype or surgery in a Kaplan-Meier analysis.CONCLUSION: The present study demonstrated enhanced formation of APLAs in CD patients. However,presence of different APLAs were not associated with the clinical phenotype or disease course.

PGE₂Generation in Myocardium from Isolated Rat Atrium under Hypoxia and Reoxygenation Conditions. Effect of Anti-<i>β</i>₁IgG from Patients with Chronic Severe Periodontitis

Background: Hypoxia is one of the most frequently encountered stresses in health and disease. Methods: We compared the effects of an anti-β1 periodontal IgG (pIgG) and an authentic β1 adrenergic agonist, xamoterol, on isolated myocardium from rat atria contractility. We used an ELISA assay to measure the generation of PGE2 in vitro after the addition of either the antibody or the adrenergic agonist. We analyzed the myocardium histopathologically in the presence of both the antibody and/or the adrenergic agonist drug during normoxia, hypoxia and reperfusion conditions. Results: PGE2 generation increased during the hypoxia and was unchanged during reoxygenation period compared with the production of this prostanoid in atria during normoxia condition. A β1 specific adrenoceptor antagonist atenolol and the β1 synthetic peptide abrogated the increment of the prostanoid in the presence of pIgG but only atenolol due to it in the presence of xamoterol. The increment of PGE2 was dependent on the activation of cox-1 and cox-2 isoforms. Moreover, cox-2 was more active and produced more increments in the production of PGE2 in the presence of the pIgG than cox-1 activation. Histopathologically, studies of myocardium specimens during these different periods of the experimental protocol: basal (B), hypoxia (H) and reoxygenation (R), were also performed and showed tissue necrosis and edematization at the myocardium level. Conclusion: The phenomenon studied here supports the notion that PGE2 may be responsible for tissue edematization. PGE2 maybe acts as a beneficial modulator in the myocardium and prevents a major injury of it. The inflammation damage to the heart organ and cardiomyocytes caused by the actions of the antibodies in the course of heart lesions provoked by cardiovascular autoimmune disease, explains some of these results obtained in the present experiments. Further studies will be needed to establish the real role of PGE2 during hypoxia injury of the heart in the course of autoimmune diseases.

Immune-mediated necrotizing myopathy:Report of two cases

BACKGROUND Immune-mediated necrotizing myopathy is a rare autoimmune myopathy characterized by muscle weakness and elevated serum creatine kinase,with unique skeletal muscle pathology and magnetic resonance imaging features.CASE SUMMARY In this paper,two patients are reported:One was positive for anti-signal recognition particle antibody,and the other was positive for anti-3-hydroxy-3-methylglutaryl coenzyme A reductase antibody.CONCLUSION The clinical characteristics and treatment of the two patients were analysed,and the literature was reviewed to improve the recognition,diagnosis,and treatment of this disease.

Limbic Encephalitis Associated with Anti-y-aminobutyric Acid B Receptor Antibodies： A Case Series from China

Background： Autoimmune encephalitis associated with antibodies against γ-aminobutyric acid B receptor （GABABR） in patients with limbic encephalitis （LE） was first described in 2010. We present a series of klan Chinese patients tbr further clinical refinement. Methods： Serum and cerebrospinal fluid （CSF） samples from patients referred to the program of encephalitis and paraneoplastic syndrome of Peking Union Medical College Hospital were tested with indirect immunofluorescence. Clinical information of patients with anti-GABABR antibody positivity was retrospectively reviewed, and descriptive statistical analysis was performed. Results： All eighteen anti-GABABR antibody-positive cases had limbic syndromes, and electroencephalogram （EEG） or neuroimaging evidence fulfilled the diagnostic criteria of LE. Four patients had additional antibodies against Hu in serum and one had anti-N-methyl-d-aspartate receptor antibody in both sera and CSF. Seventeen （17/18） patients presented with new-onset refractory seizure or status epileptics. Twelve （12/18） patients had memory deficits, 11 （11/18） patients had personality change, 7 （7/18） patients had disturbance of consciousness, and 3 （3/18） patients showed cerebellar dysfunction. One patient with LE had progressive motor and sensory polyneuropathy. Lung cancer was detected in 6 （6/18） patients. Ten （10/18） patients showed abnormality in bilateral or unilateral mediotemporal region on magnetic resonance imaging. Ten （10/18） patients had temporal lobe epileptic activity with or without general slowing on EEG. Seventeen patients received immunotherapy and 15 of them showed neurological improvement. Four patients with lung cancer died within 1-12 months due to neoplastic complications. Conclusions： Our study demonstrates that most Han Chinese patients with anti-GABABR antibody-associated LE have prominent refractory epilepsy and show neurological improvement on immunotherapy. Patients with underlying lung tumor have a relatively poor prognosis. Testing for anti-GABABR antibodies is necessary for patients with possible LE or new-onset epilepsy with unknown etiology.

Systematic mutational analysis of epitope-grafted ED3 immunogenicity reveals a DENV3-DENV4 bi-serospecific ED3 mutant

Objective:To identify the residue determinants of the serospecificity and sero-cross-reactivity of dengue virus(DENV)envelope protein domain 3(ED3),which contains two major putative epitopes of DENV.Methods:We constructed ED3 from DENV3(3ED3)and DENV4(4ED3),and six epitope-grafted variants,where we transferred epitope 1(L304I,K305D,V309M,and S310A)and/or epitope 2(D383N,K384S,K387T,and N389H)of 4ED3 onto 3ED3 and vice-versa.Swiss albino mice aged 3-4 weeks were immunized against wildtype and epitope-grafted ED3 variants and anti-ED3 IgG antibody responses were determined using ELISA.Results:Mouse immunization using 3ED3 and 4ED3 generated serotype-specific antisera,as expected.Similarly,most epitope-grafted ED3s produced antisera serospecific to the template ED3 with little or no cross-recognition of ED3 of the serotype from which the epitopes were taken.These indicated that a mere grafting of the epitope was not sufficient to transfer serospecificity,contrary to our expectations.However,one epitope-grafted ED3 mutant,where epitope 1 of 3ED3 was grafted onto 4ED3(4ED3^(epi1)),generated antisera that was serospecific to both 4ED3 and 3ED3.Conclusions:The 4ED3^(epi1)is a chimeric ED3 that produces antisera possessing serospecificity to both 3ED3 and 4ED3 onto a common 4ED3 scaffold.The 4ED3^(epi1),therefore,provides a unique tool for analyzing serospecificity and sero-cross-reactivity in dengue.We believe that chimeric ED3 may provide a template for future recombinant ED3 possessing serospecificity of multiple DENVs onto a single scaffold and may pave a way developing tri-and/or tetravalent anti-DENV antisera.

Antiphospholipid syndrome and its role in pediatric cerebrovascular diseases: A literature review

Antiphospholipid syndrome(APS)or Hughes syndrome is an acquired thromboinflammatory disorder.Clinical criteria of APS diagnosis are large-and small-vessel thrombosis as well as obstetric problems;laboratory criteria are the presence of antiphospholipid antibodies(lupus anticoagulant,anticardiolipin antibodies and anti-β2-glycoprotein-1).The presence of at least 1 clinical and 1 laboratory criterion allows definitive diagnosis of APS.Primary APS is diagnosed in patients without features of connective tissue disease;secondary APS is diagnosed in patients with clinical signs of autoimmune disease.A high frequency of catastrophic APS as well as a high tendency to evolve from primary APS to secondary syndrome during the course of lupus and lupus-like disease is a feature of pediatric APS.The most characteristic clinical presentation of APS in the pediatric population is venous thrombosis,mainly in the lower limbs,and arterial thrombosis causing ischemic brain stroke.Currently,no diagnostic criteria for pediatric APS exist,which probably results in an underestimation of the problem.Similarly,no therapeutic procedures for APS specific for children have yet been established.In the present literature review,we discussed data concerning APS in children and its role in cerebrovascular diseases,including pediatric arterial ischemic stroke,migraine and cerebral venous thrombosis.

Blockade of γc Signals in Combination with Donor-specific Transfusion Induces Cardiac Allograft Acceptance in Murine Models

The γc cytokines play an important role in proliferation and survival of T cells. Blocking the γc signals can cause the activated donor-reactive T cells losing the ability to proliferate, and getting into apoptosis pathway, which contributes to induction of the peripheral tolerance. In this study, we induced the transplant tolerance through blocking the γc in combination with donor-specific transfusion (DST) in the cardiac transplantation. Following DST, on the day 2, 4 and 6, C57BL/6 recipients received anti-γc monoclonal antibodies (mAbs) injection, and those in control group were not given anti-γc mAbs. On the day 7, Balb/c cardiac allografts were transplanted. All recipients in experimental group accepted cardiac allografts over 30 days, and two of them accepted allografts without rejection until sacrifice on the 120 day. Animals only receiving DST rejected grafts within 5 days, and the mice receiving cardiac transplantation alone rejected grafts within 9 days. Our study showed that blockade of γc signaling combined with DST significantly prolonged allograft survival, which was probably associated with inhibition of antigen-specific T-cell proliferation and induction of apoptosis.

Anti-β2GPI/β2GPI complexes induce platelet activation and promote thrombosis via p38MAPK: a pathway to targeted therapies

Anti-β2 glycoprotein I(anti-β2GPI)antibodies are important contributors to the development of thrombosis.Anti-β2GPI antibody complexes withβ2GPI are well known to activate monocytes and endothelial cells via the intracellular NF-kB pathway with prothrombotic implications.By contrast,the interaction of anti-β2GPI/β2GPI complexes with platelets has not been extensively studied.The p38 mitogen-activated protein kinase(MAPK)pathway has been recognized to be an important intracellular signaling pathway in the coagulation cascade and an integral component of arterial and venous thrombosis.The present study reveals that levels of anti-β2GPI/β2GPI complexes in sera are positively associated with p38MAPK phosphorylation of platelets in thrombotic patients.Furthermore,SB203580 inhibits anti-β2GPI/β2GPI complex-induced platelet activation.Thrombus formation decreased in p38MAPK−/−mice after treatment with anti-β2GPI/β2GPI complexes.In conclusion,p38MAPK may be a treatment target for anti-β2GPI antibody-associated thrombotic events.