Antibodies In Sera Of Patients Research Articles

Serum total sialic acid and Hanganutziu-Deicher antibody in normals and in cancer patients

To determine the levels of both TSA and HD antibody in sera of patients with various malignancies and evaluate their potential role as diagnostic and/ or prognostic markers. Laboratory based analysis. Kenyatta National Hospital, Kenya Medical Research Institute and the Department of Biochemistry, University of Nairobi. A total of 909 serum samples, 420 from cancer patients recruited at Kenyatta National Hospital and 509 from normal blood donors recruited at Nairobi Hospital. The mean age for the patients and controls was 36 and 37 years respectively. Carcinoma patients constituted 54%, sarcoma 12.1%, lymphoma 16.4% and 17.4% had other types of tumours. The mean TSA in patients was 0.86 mg/ml +/- 0.026 compared to 0.82 mg/ml +/- 0.014 in controls. The TSA level was significantly higher in patients compared to controls (Student's t-test p = 0.031 at 0.05 confidence level). The TSA increased with age in both study groups. In patient sera, both gender gave the same mean of 0.83 mg/ml while it was 0.82 mg/ml and 0.83 mg/ml in control females and in males respectively. Sarcomas had the highest amount of 0.93 mg/ml but there was no significant statistical variation between tumour types (p = 0.076). The HD antibody mean readings were 0.004 in pathologic sera compared to 0.011 in controls. The values were significantly elevated in patients (p = 0.03) with females giving a higher value for both study groups (p = 0.628). HD antibody readings was significantly higher in carcinomas (p = 0.017) compared to those of sarcomas and lymphomas. There was no association between antibody readings and age of patient (p = 0.601). Both TSA and HD antibody values were significantly elevated in patients compared to clinically healthy controls and while TSA levels increased with age and was independent of gender, HD antibody levels were independent of age, gender and also tumour type. The study demonstrates that although TSA is normally elevated in malignancy, most of the sialic acid shed is of N-acetyl type as some patients do not express HD antibody directed to the N-glycolyl sialic acid. The reason why some tumours would express Neu5Gc at any one time needs further evaluation.

Progress in Serodiagnosis of Mycobacterium tuberculosis Infection

One-third of the world population is estimated to have Mycobacterium tuberculosis infection. Accurate and timely identification of infected individuals is critical for treatment and control. The current diagnostic methods lack the desired sensitivity and specificity, require sophisticated equipment and skilled workforce or take weeks to yield results. Diagnosis of extrapulmonary TB, TB-HIV co-infection, childhood TB and sputum smear-negative pulmonary TB pose serious challenges. Interest in developing serodiagnostic methods is increasing because detection of antibody is rapid, simple and relatively inexpensive, and does not require a living cell for detection. Three types of tests, namely screening tests to overcome diagnostic delay, specific tests for diagnosis of extrapulmonary TB and other bacteriologically negative cases, and tests for vaccine-induced immunity need critical consideration. Several factors must be considered to develop serodiagnostic methods for TB. Antigen recognition by infected individuals is highly heterogeneous due to stage of disease, differences in HLA types, strain of the bacilli, health of the patient and bacillary load. With advances in molecular biological techniques, a number of novel antigens have been identified. Some of these antigens have proven valuable in detecting specific antibodies in some of the most challenging TB patients. The best example is a fusion protein containing several M. tuberculosis proteins (e.g. CFP-10, MTB8, MTB48, MTB81 and the 38-kDa protein) which showed encouraging results in detecting antibodies in sera of patients, including TB-HIV co-infection. This review presents progress made in the serodiagnosis of TB during the last decade.

Role of Anti–Glycoproteins D (Anti–gD) and K (Anti–gK) IgGs in Pathology of Herpes Stromal Keratitis in Humans

To assess the relative impact of antibodies specific for HSV-1 glycoproteins on eye disease in response to HSV-1 infection, the composition of antibodies specific for 10 of the viral glycoproteins, and the effect of anti-glycoprotein (g)D and anti-gK antibodies on antibody-dependent enhancement (ADE). In a prospective case-control study, sera from patients with a history of herpes stromal keratitis (HSK) were compared with sera from nonocular HSV-1-seropositive and HSV-seronegative control subjects. HSV-1 neutralizing antibody titer and type-specific IgG and IgM were measured. In addition, the presence of anti-HSV-1 gD and gK antibodies in the sera of all patients also was determined by ELISA using gD and gK antigens. Finally, the role of anti-gD- and gK-specific antibodies to ADE was investigated. Average neutralizing antibody titers and levels of HSV-1 IgG were similar between HSK- and non-HSK-seropositive patients. However, the contribution of gD to the neutralizing antibody titer in HSK sera was significantly lower than that in non-HSK-seropositive patients, despite higher anti-gD ELISA titers. Overall, sera from patients with HSK had higher anti-gK antibody titers and induced ADE in vitro compared with non-HSK or seronegative sera. The ADE response in HSK sera was attributed to anti-gK antibody. These results suggest that sera from HSK patients had higher anti-gD and -gK antibody titers than sera from seropositive patients who had no history of HSK despite similar levels of neutralizing antibody titers and HSV-1 IgG, that HSK sera induced ADE whereas sera from non-HSK patients did not induce ADE, and that anti-gD antibody in sera of HSK patients contributed less to the HSV-1 neutralization antibody titer than did sera from non-HSK patients.

Multiple specificities of autoantibodies against hnRNP A/B proteins in systemic rheumatic diseases and hnRNP L as an associated novel autoantigen

Spliceosomal small nuclear ribonucleoproteins (U-snRNPs) are frequent and specific targets of autoantibodies in systemic rheumatic diseases. The abundant, functionally related heterogeneous nuclear ribonucleoprotein complexes (hnRNPs) have later defined as a new target of autoantibodies, of which their immunochemical/immunogenic and pathogenic properties are still under investigation. Among hnRNP proteins, those belonging to the A/B type are considered as the major autoantigens targeted by antibodies in sera of patients suffering with rheumatoid arthritis (RA), systemic lupus erythematosus (SLE) and mixed connective tissue disease (MCTD). By performing an extensive screening using rat liver 40S hnRNP antigenic material, we document here the existence of multiple specificities of anti-hnRNP A/B autoantibodies in sera of Greek patients suffering with a spectrum of systemic rheumatic diseases. This included patients with SLE, Sjogren's syndrome (SS), Scleroderma (SSc) and a specific group of patients mostly with undifferentiated disease (UD patients). In total, four distinct types of anti-hnRNP A/B autoantibodies have been recognized. The first two referred to the known anti-hnRNPA2(RA33) and anti-hnRNP A1; the latter appearing very rarely. The third was of the new type selectively reacting with hnRNP B2 and an hnRNP A3 variant, while the fourth was a rare case of anti-hnRNP B2 alone. In addition, a novel specificity of autoantibodies against hnRNP L protein was identified in association with anti-hnRNP A/B antibodies. The co-existence within a serum of autoantibodies having variable specificity for hnRNP A/B and L autoantigens was shown. Specific immunochemical features of the identified autoantibodies are presented and a possible mechanism of autoepitope spreading within protein components of hnRNP complexes is discussed.

Detection of antibodies reacting with the antithetical duffy blood group antigens Fy a and Fy b using recombinant fusion proteins containing the duffy extracellular domain

Detecting blood group-specific antibodies in patient sera is essential to the management of blood transfusions or pregnancies. We produced the antithetical forms of the 65 amino acid extracellular domain (ECD) of the Duffy (Fy) blood group protein fused to glutathione sulfotransferase (GST): GST-Fy a; and GST-Fy b, differing only in Gly or Asp at position 44, respectively. The purified recombinant proteins were recognized more effectively by reference polyclonal or monoclonal antibodies than the antithetical Fy specificity by either ELISA or immunoblotting. Combined immunoblot and ELISA tests performed at 1:200 dilutions of sera using the recombinant proteins gave results in agreement with undiluted sera and agglutination for 17/19 alloimmunized patients. At 1:200, agglutination detected anti-Fy a or anti-Fy b in only three of 12 samples that were positive by ELISA. Recombinant ECD-Fy proteins are suitable and sensitive reagents for the detection of anti-Fy that use technology amenable to automation and/or miniaturization and avoid the need for intact red cells.

Recombinant antigens as diagnostic markers for aspergillosis

Eight recombinant proteins and purified galactomannan of Aspergillus fumigatus were tested by enzyme-linked immunosorbent assay to quantify the anti- Aspergillus antibodies in sera of patients with aspergilloma, allergic bronchopulmonary aspergillosis (ABPA), and invasive aspergillosis (IA). In spite of the variability observed in the immune responses of individual patients, quantification of the antibody titers against the 18-kDa ribonuclease (RNU), the 360-kDa catalase (CAT), and the 88-kDa dipeptidylpeptidase V (DPPV) was useful for the diagnosis of aspergilloma and ABPA. Differential diagnosis of ABPA was even possible among cystic fibrosis as well as noncystic fibrosis patients. In the group of immunocompromised patients with IA, no antibody response was mounted in response to the Aspergillus infection in any of the patients. Interestingly, about half of the patients with proven IA came to the hospital with high titers of anti- Aspergillus antibodies, suggesting that they were infected upon entry to the hospital. These results suggest that recombinant RNU, CAT, and DPPV have a great potential in the serodiagnosis of all forms of aspergillosis in the immunocompromised and immunocompetent patient.

Rapid and simple detection of IFN‐neutralizing antibodies in chronic hepatitis C non‐responsive to IFN‐α

Different mechanisms have been proposed for the failure of interferon (IFN) therapy in patients with chronic hepatitis C and multiple sclerosis, for example, the presence of IFN-neutralizing antibodies. In this study, a novel assay system based on the IFN-inducible Mx-promoter was used to detect IFN-neutralizing antibodies in sera of patients with chronic hepatitis C. To monitor IFN bioactivity in IFN-treated patients, a real-time RT-PCR for MxA gene expression in PBMCs was established. Using these two methods, patients with chronic hepatitis C virus (HCV) infection receiving IFN therapy and patients with treatment induced HCV clearance were monitored. Importantly, neutralizing anti-IFN antibodies were detected in the sera of 3 of 38 chronically HCV-infected patients who failed to respond to therapy but none in sera of patients who cleared HCV after IFN therapy. Interestingly, the presence of these antibodies correlated with the lack of MxA induction in PBMCs after initiation of IFN-alpha therapy. Retrospective analysis of one patient's sera revealed that the anti-IFN-alpha antibodies had already developed after the first of four unsuccessful IFN therapies, suggesting that neutralizing antibodies may have contributed to the failure of previous IFN treatments. In summary, a novel screening assay was established that may be helpful for testing IFN non-responders for the presence of clinically relevant anti-IFN-alpha antibodies and for selecting alternative IFN preparations not neutralized by these antibodies.

Autoantibodies against human epithelial cells and endothelial cells after severe acute respiratory syndrome (SARS)‐associated coronavirus infection

The severe acute respiratory syndrome (SARS) is caused by infection with the SARS‐associated coronavirus (SARS‐CoV) and characterized by severe pulmonary inflammation and fibrosis. In this study, the development of autoantibodies against human epithelial cells and endothelial cells in patients with SARS at different time periods (the first week: phase I, 1 month after the disease onset: phase II/phase III) were investigated. Antibodies in sera of patients and healthy controls against: (1) A549 human pulmonary epithelial cell‐line, (2) human umbilical venous endothelial cells (HUVEC), (3) primary human pulmonary endothelial cells (HPEC) were detected by cell‐based ELISA and indirect immunofluorescence staining. The results revealed that serum levels of IgG anti‐A549 cells antibodies, IgG anti‐HUVEC antibodies, and IgM anti‐HPEC antibodies were significantly higher in SARS patients at phase II/phase III than those in healthy controls. Sera from SARS patients at phase II/phase III could mediate complement dependent cytotoxicity against some A549 cells and HPEC. It is concluded that some autoantibodies against human epithelial cells and endothelial cells would be developed after SARS‐CoV infection and this phenomenon may indicate post‐infectious cellular injury and also induce SARS‐induced immunopathology. J. Med. Virol. 77:1–7, 2005. © 2005 Wiley‐Liss, Inc.

ANTI-RIBOSOMAL P ANTIBODIES ARE ASSOCIATED WITH NEPHRITIS, VASCULAR THROMBOSIS AND LYMPHOCYTOPENIA IN PATIENTS WITH SYSTEMIC LUPUS ERYTHEMATOSUS

In the present study, anti-ribosomal P antibody in sera of patients with systemic lupus erythematosus was assayed using an enzyme-linked immunosorbent assay, and its association with clinical symptoms of the patients was analyzed. The presence of anti-ribosomal P antibody was associated with increased frequency of lupus nephritis in the presence of anti-DNA antibody, and was associated with increased frequency of vascular thrombosis in the presence of anti-beta2 glycoprotein I antibody and/or lupus anticoagulant. The level of anti-ribosomal P antibody correlated inversely with the peripheral lymphocyte counts.

Analysis of the major proteins secreted by the human opportunistic pathogenAspergillus fumigatusunderin vitroconditions

Although secreted proteins of pathogenic microorganisms often represent potential virulence factors, so far only limited information has been available on the proteins secreted by Aspergillus fumigatus. We therefore analysed supernatant proteins after growth in different media. In serum-free cell culture medium A. fumigatus growth was limited and no protein secretion was detectable, whereas distinct protein patterns were detectable after growth in either aspergillus minimal medium (AMM) or the more complex yeast glucose medium (YG). The three major proteins secreted under these conditions were identified as the ribotoxin mitogillin, a chitosanase and the aspergillopepsin i. Mitogillin and chitosanase were secreted in AMM, whereas aspergillopepsin i was especially prominent after growth in YG. When the AMM cultures reached stationary phase, seven additional major proteins were detectable. Two of them were identified as the chitinase chiB1 and a beta(1-3) endoglucanase. Conditioned medium containing mitogillin and chitosanase did not have a detectable cytotoxic effect on A549 and Vero cells. Using recombinant mitogillin and chitosanase we detected anti-chitosanase and antimitogillin antibodies in sera of patients suffering from invasive aspergillosis or aspergilloma, but not in control sera of healthy individuals. This suggests that chitosanase, like mitogillin, is expressed during infection and might therefore be of diagnostic relevance.

Conformational Difference in HMGB1 Proteins of Human Neutrophils and Lymphocytes Revealed by Epitope Mapping of a Monoclonal Antibody

HMGB1 and HMGB2 are abundant nonhistone chromosomal proteins in eukaryotic organisms. Their respective primary sequences are highly conserved. Our previous studies showed that these proteins are novel autoantigens of anti-neutrophil cytoplasmic antibodies in sera from patients with ulcerative colitis (UC), rheumatic disease and autoimmune hepatitis (AIH). In the present paper, we showed that anti-HMGB1 and HMGB2 antibodies in sera of patients with UC do not recognize HMGB1 in neutrophils while they recognize the protein in lymphocytes. Anti-HMGB2 monoclonal antibody FBH7, recognizing HMGB1 in lymphocytes, showed a similar profile to the antibodies in the patients' sera. In order to elucidate the difference in immunoreactivity to HMGB1 between neutrophils and lymphocytes, we mapped the epitope for FBH7 by means of several methods. The results showed that FBH7 recognizes the intact conformation composed of 52-56 residues of HMGB1 in lymphocytes. This suggested that HMGB1 in neutrophils is conformationally changed in the epitope or the peripheral structure of the epitope from the protein in lymphocytes. The apparent conformational change of HMGB1 between neutrophils and lymphocytes will be important for understanding the functional difference of HMGB1 in these cells.

Construction of prokaryotic expression system of 2 148-bp fragment fromcagAgene and detection ofcagAgene, CagA protein inHelicobacter pyloriisolates and its antibody in sera of patients

To construct a prokaryotic expression system of a Helicobacter pylori (H pylori) cagA gene fragment and establish enzyme-linked immunosorbent assays (ELISA) for detecting CagA and its antibody, so as to understand the manner in which the infection of CagA-expressing H pylori (CagA(+) H pylori) isolates cause diseases. H pylori strains in gastric biopsy specimens from 156 patients with positive results in rapid urease test were isolated. PCR was used to detect the frequency of cagA gene in the 109 H pylori isolates and to amplify a 2 148-bp fragment (cagA1) of cagA gene from a clinical strain Y06. A prokaryotic expression system of cagA1 gene was constructed, and the expression of the target recombinant protein (rCagA1) was examined by SDS-PAGE. Western blotting and immunodiffusion assay were employed to determine the immunoreactivity and antigenicity of rCagA1, respectively. Two ELISAs were established to detect CagA expression in 109 H pylori isolates and the presence of CagA antibody in the corresponding patients' sera, and the correlations between infection with CagA(+) H pylori and gastritis as well as peptic ulcer were analyzed. Of all the clinical specimens obtained, 80.8% (126/156) were found to have H pylori isolates and 97.2% of the isolates (106/109) were positive for cagA gene. In comparison with the reported data, the cloned cagA1 fragment possessed 94.83% and 93.30% homologies with the nucleotide and putative amino acid sequences, respectively. The output of rCagA1 produced by the constructed recombinant prokaryotic expression system was approximately 30% of the total bacterial protein. rCagA1 was able to bind to the commercial antibody against the whole-cells of H pylori and to induce the immunized rabbits to produce antibody with an immunodiffusion titer of 1:4. A proportion as high as 92.6% of the H pylori isolates (101/109) expressed CagA and 88.1% of the patients' serum samples (96/109) were CagA antibody-positive. The percentage of CagA(+) H pylori strains (97.9%) isolated from the biopsy specimens of peptic ulcer appeared to be higher than that from gastritis (88.5%), but the difference was not statistically significant (chi (2)=3.48, P>0.05). rCagA1 produced by the prokaryotic expression system constructed in this study possesses good immunoreactivity and antigenicity, and the established ELISAs can be used to detect CagA of H pylori and its antibody. H pylori isolates show high frequencies of cagA gene and CagA expression, but the infections by CagA(+) H pylori strains are not the most decisive factors to cause gastric diseases.

A streptavidin-biotin-based microarray platform for immunoassays.

The authors describe a microarray system for disease diagnosis based on antibody-antigen interactions. Either biotinylated antibodies or antigens are coupled via streptavidin linkers onto a gold surface. This platform has been used to establish recombinant antibody-antigen interactions and to detect specific IgM antibodies in sera of patients suspected of Lyme borreliosis. Therefore, this microarray system can be adapted for further applications.

Antiphospholipid (Hughes) syndrome: a review with update

AbstractThis article reviews the evolution of the concept of Hughes syndrome starting with the discovery of beef heart extract‐reactive antibodies in sera of patients with syphilis, presence of such antibodies in some normal individuals who went on to develop systemic lupus erythematosus (SLE), identification of the antigen as anionic phospholipids and some of the cofactors of the blood coagulation cascade, development of more refined techniques for detecting such antibodies and finally its implication in the causation of an acquired hypercoagulable state. The review then discusses the results of extensive international collaborative efforts of the major centres with interest and expertise in Hughes syndrome. It summarizes the recently enunciated classification criteria for this disease. The results and the implications of some of the recent seminal papers, especially on the frequency of different clinical manifestations in a large cohort of patients followed over long‐periods, and recommendations for long‐term high‐intensity anticoagulation for the optimum management of this disease, are also discussed.

Western blotting using Strongyloides ratti antigen for the detection of IgG antibodies as confirmatory test in human strongyloidiasis.

The present study was conducted to evaluate the frequency of antigenic components recognized by serum IgG antibodies in Western blotting (WB) using a Strongyloides ratti larval extract for the diagnosis of human strongyloidiasis. In addition, the WB results were compared to the enzyme-linked immunosorbent assay (ELISA) and the indirect immunofluorescence antibody test (IFAT) results. Serum samples of 180 individuals were analyzed (80 with strongyloidiasis, 60 with other intestinal parasitoses, and 40 healthy individuals). S. ratti was obtained from fecal culture of experimentally infected Rattus rattus. For IFAT, S. ratti larvae were used as antigen and S. ratti larval antigenic extracts were employed in WB and ELISA. Eleven S. ratti antigenic components were predominantly recognized by IgG antibodies in sera of patients with strongyloidiasis. There was a positive concordance for the three tests in 87.5% of the cases of strongyloidiasis. The negative concordance in the three tests was 94% and 97.5%, in patients with other intestinal parasitoses and healthy individuals, respectively. In cases of positive ELISA and negative IFAT results, diagnosis could be confirmed by WB. ELISA, IFAT, and WB using S. ratti antigens showed a high rate of sensitivity and specificity. In conclusion, WB using S. ratti larval extract was able to recognize 11 immunodominant antigenic components, showing to be a useful tool to define the diagnosis in cases of equivocal serology.

Autoreactive helper T cells specific for cytokeratin 19 in patients with autoimmune hepatitis

Recently we have demonstrated the existence of anti-cytokeratin 19 (CK19) antibodies in sera of patients with autoimmune hepatitis (AIH). In the present study, we examined the existence of T lymphocytes specific for CK19 in patients with AIH. The frequency of responders having CK19-specific T lymphocytes was significantly higher in AIH patients than in chronic hepatitis C (CH-C) patients and normal subjects. Furthermore, the stimulation index of proliferative responses of peripheral blood mononuclear cells (PBMCs) was significantly higher in AIH patients than in CH-C patients and normal subjects. The phenotype of proliferating PBMCs specific for CK19 was shown to be predominantly CD4 + T lymphocytes and these CD4 + T lymphocytes had a Th1 subtype. The present findings demonstrate that there is some population of CD4 + T lymphocytes with a Th1 subtype specific for CK19 in peripheral blood of patients with AIH. The Th1-predominat pattern of cytokines may induce cytotoxic T lymphocytes (CTLs) specific for the antigenic peptides derived from the autoantigen, including CK19. In addition, these CTLs may attack the hepatocytes and this may be one of the important etiologies of AIH.

Extracts of lung cancer cells reveal antitumour antibodies in sera of patients with lung cancer.

The objective of the present study was to reveal antitumour antibodies in sera of patients with small cell lung cancer (SCLC). The antibodies in sera of patients with SCLC and other tumours were detected by immunoblotting with whole extracts of SCLC cells as the antigen source. Sera of patients with various pulmonological disorders, irradiated during the liquidation of consequences of the Chernobyl nuclear power plant incident (a high-risk group in lung cancer), were also analysed. The present authors' found that SCLC sera contain a set (pattern) of antitumour antibodies which are rarely detected in sera of patients with cancers different from SCLC and very rarely, if ever, present in sera of healthy individuals. The sensitivity and the specificity of the pattern are equal to 80% and 91%, correspondingly. In the high-risk group in lung cancer, the frequencies of the antibodies are somewhat lower than the corresponding values in SCLC sera, but significantly larger than those in healthy sera. The findings of the present study create a basis for clinical application of the antitumour antibodies described.

Local production of Ro/SSA and La/SSB autoantibodies in the target organ coincides with high levels of circulating antibodies in sera of patients with Sjögren's syndrome

Objective: To analyze Ro and La autoantibody levels in the periphery and production in the target organ in patients with Sjögren's syndrome.Methods: The autoantibody production against the Ro and La proteins was investigated in 12 patients with Sjögren's syndrome. ELISA with recombinant antigens was used to determine levels in sera. The distribution of the antibody‐producing plasma cells in the target organ was studied by immunohistochemistry using biotinylated antigens.Results: All investigated patients with Sjögren's syndrome had detectable levels of Ro and La antibodies in sera, while local antibody‐production in the salivary glands was restricted to patients with high antibody levels. The autoantibody‐producing cells were identified at the periphery of the infiltrates and in interstitial spaces.Conclusions: The chronic inflammation of the salivary glands in Sjögren's syndrome may be a self‐sustaining process promoting autoantibody production in the target organ, possibly contributing to increased serum levels of autoantibodies.

Atopic dermatitis and Malassezia species: a study of antigenic components of Malassezia species for immunoglobulin E of patients with atopic dermatitis

Antigenic components extracted by treatment with beta-mercaptoethanol from M. furfur, M. globosa, M. restricta, M. slooffiae, and M. sympodialis were studied for immunoglobulin E antibodies in sera of patients with atopic dermatitis. CBB staining and lectin blots of the extracts showed that each Malassezia species contained species-dependent components at the protein level. In a Western blot with the 2-ME extracts,IgE antibodies against the Malassezia species were found in sera of 83% (for M. globosa), 74% (for M. sympodialis), 65% (for M. furfur), 56% (for M. restricta) and 50% (for M. slooffiae) of the AD patients. In the Western blot inhibition test, the 2-ME extract of M. globosa partially inhibited the reaction of the antigenic components of other Malassezia species with the patients IgE antibodies. These results indicated that Malassezia species contained both species-specific and common antigenic components at the IgE antibody level. A major component of M. globosa was isolated from the 2-ME extract of this fungus by ion-exchange column chromatography and was referred to as Malg46b. Dot blot with the Malg46b containing fraction immunologically reacted with 69% of the sera of the patients, and with 83% of the sera of those who were positive for IgE antibodies to the 2-ME extract of M. globosa in Western blot. The intensities generated for each dot correlated well with the total intensities generated for the 2-ME extract of M. globosa in Western blot (r=0.763) The polyclonal antibody to Malg46b reacted strongly only with the 2-ME extract of M. globosa and reacted slightly with M. restricta. These results indicate that a glycoprotein, Malg46b of M. globosa, is dominantly expressed in this fungus and is a possible major antigen for IgE antibodies in patients with AD.

Activation of extracellular signal regulated kinase 1/2 in human dermal microvascular endothelial cells stimulated by anti-endothelial cell antibodies in sera of patients with Behçet's disease

Anti-endothelial cell antibodies (AECA) have been detected in the sera of patients with Behçet's disease (BD). The isotype of AECA from BD is IgM recognizing 44 kDa antigen (IgM-AECA) of human dermal microvascular endothelial cells (HDMEC). After stimulation of HDMEC with AECA-positive sera from BD patients, the expression of intercellular cell adhesion molecule-1 (ICAM-1) on HDMEC increases significantly. Mitogen-activated protein kinase (MAPK) cascade is one of protein kinase families activated by a wide spectrum of extracellular stimuli. There are several subtypes, including extracellular signal regulated kinase (ERK)1/2, c-Jun NH 2 terminal kinase (JNK), and p38 cascades, and they regulate various cellular processes such as cell growth, differentiation, and inflammation. We examined the involvement of MAPK as a signal transduction pathway in the IgM-AECA-induced ICAM-1 expression. We used enzyme-linked immunosorbent assay (ELISA) and fluorescence-activated cell sorting (FACS) for detecting the induction of ICAM-1 on HDMEC. We also examined the production of tumor necrosis factor α (TNFα) or interleukin-1α (IL-1α) by HDMEC after stimulation with IgM-AECA, and checked the involvement of MAPK by Western blot assay. IgM-AECA cocktail from 8 patients with BD induced expression of the ICAM-1 on HDMEC. Neither TNFα nor IL-1α was detected by ELISA, FACS or reverse transcriptase-polymerase chain reaction in activated HDMEC cultures. IgM-AECA cocktail activated ERK1/2 and showed peak activities at 5 min after the stimulation. Specific MAPK/ERK kinase inhibitor PD98059 inhibited IgM-AECA-induced ERK1/2 activities and ICAM-1 expression on HDMEC at a concentration of 60 μM. IgM-AECA can play a pathogenic role in induction of vasculitis and inflammatory lesions of BD by directly activating endothelial cells, not by production of TNFα or IL-1α from HDMEC. ERK1/2 are involved in expression of ICAM-1 on HDMEC stimulated with IgM-AECA.