Antibacterial and antipeptide antibodies in Japanese and Finnish patients with rheumatoid arthritis

It has been suggested that Proteus infection may be involved in the pathogenesis of rheumatoid arthritis (RA). Bacterial and peptide immune responses in patients with RA and other control subjects were investigated in two geographically different populations. Serum samples from Finnish patients with early (n=72) and advanced (n=27) RA and 30 Finnish healthy controls, as well as from Japanese RA patients from two different locations: Tokyo (n=30) and Otsu (n=30), 18 patients with systemic lupus erythematosus (SLE) and 23 Japanese healthy controls were all screened for the total, and class-specific (IgG, IgA and IgM) antibodies against Proteus mirabilis, Escherichia coli and Serratia marcescens by indirect immunofluorescence assay. These samples were also tested for the determination of levels of isotypic antibodies against the shared epitope involving 16-mer synthetic peptides containing the EQRRAA or ESSRAL sequences and compared to scrambled control peptide by using an enzyme-labeled immunosorbent assay method. Significantly elevated levels of IgG and IgM antibodies to P. mirabilis and antibodies against both EQRRAA and ESSRAL peptides were detected in sera of Finnish patients with early and advanced RA, and in Japanese patients from Otsu or Tokyo compared to their corresponding control groups. In contrast, no difference either in the total or in any of the isotypic antibodies were observed between these groups when serum samples were screened against each of E. coli and S. marcescens or against the control peptide. Furthermore, there was a significant correlation between the antibody levels against Proteus bacteria only and both EQRRAA and ESRRAL peptides. Our findings support the possibility for specific involvement of P. mirabilis in the etiopathogenesis of RA even in early cases.Abbreviations ELISA Enzyme linked immunosorbent assay - IIF Immunofluorescence - RA Rheumatoid arthritis - SLE Systemic lupus erythematosus     

Correlation between <Emphasis Type="Italic">Yersinia enterocolitica</Emphasis> and type I collagen reactivity in patients with arthropathies

We investigated the association with Yersinia infection in patients with arthropathies in our region. To assess the reactivity to articular antigens, the correlation of anti-Yersinia with anti-type I and type II collagen antibodies was studied. Sera from 124 patients with musculoskeletal symptoms, and 47 synovial fluids (SF) from patients with rheumatoid arthritis (RA), spondyloarthopathies (SpA) or osteoarthritis (OA) were examined. Immunoglobulins against Yersinia enterocolitica, type I and type II collagens were determined by enzyme-linked immunosorbent assay. Immunoglobulin (Ig) A to Yersinia lipopolysaccharide (LPS) was present in 13/124 sera (10%) and 3/47 SF (6%). By Western blot, IgA to Yersinia outer proteins (Yops) was found in 14/124 sera (11%) and 2/47 SF (4%). Yersinia DNA from SF was not amplified by polymerase chain reaction. We found a significant correlation with anti-collagen type I but not type II antibodies. These results suggest different reactivity to articular collagen in patients with Yersinia antibodies.     

Antibodies to arthritis-associated microbes in inflammatory joint diseases

Summary IgM, IgG and IgA class antibodies againstYersinia, Salmonella, Campylobacter andBorrelia were determined by enzyme-linked immunosorbent assay (ELISA) in a group of 340 unselected patients with a recent inflammatory joint disease. The control group consisted of 340 and 100 healthy blood donors usingBorrelia-ELISA and other ELISAs, respectively. Of all the patients, 27.4% had increased antibody levels against at least one of the microbes tested. The prevalence of positive antibody levels was highest inYersinia antibodies (17.9%). The corresponding figures forSalmonella, Campylobacter andBorrelia were 7.0, 6.2 and 1.8%, respectively. Patients with entero-arthritis or clinically typical reactive arthritis who had not had gastrointestinal or urogenital symptoms previously had the highest prevalence of the microbial antibodies (67.6 and 40.7%, respectively). These findings indicate that arthritis may often have a reactive etiopathogenesis without recognized gastrointestinal infection, emphasizing the importance of microbial serology in the differential diagnosis.     

Serodiagnosis of neuroborreliosis: Comparison of reliability of three confirmatory assays

Summary The sensitivity and specificity of three confirmatory assays for the serodiagnosis of neuroborreliosis were investigated. Samples from 96 patients with proven neuroborreliosis, 80 healthy volunteers, 20 patients with neurosyphilis and 20 patients with recent infections with Epstein-Barr virus (EBV) were tested for borrelial antibodies by immunoblotting,Borrelia burgdorferi sensu lato sonicate EIA following pre-absorption of cross-reactive antibodies (Abs-EIA) and by a so-called RECO-EIA using the following recombinant borrelial proteins as antigens: a 14 kDa-internal flagellin fragment, the outer surface protein C (23 kDa) and the high molecular mass protein p83 (83 kDa). the immunoblots were evaluated according to the criteria published byEngstr?m et al. andHauser et al. An evaluation of IgM and/or IgG antibodies revealed a considerably higher sensitivity for the RECO-EIA (94%) compared to the Abs-EIA (82%, P<0.0001). Evaluation of the immunoblot according to the criteria ofHauser was significantly more sensitive than according to the criteria ofEngstr?m (89 vs 51%, P=0.0003). A higher sensitivity was demonstrated for IgM (54 vs 22%) and IgG antibodies (64 vs 24%). When both findings from RECO-EIA and immunoblotting were considered, positive findings in the first step assay (sonicate EIA without pre-absorption) were confirmed in 97% of patients. When samples were tested for IgM antibodies, the specificities of the three confirmatory assays did not differ significantly, but in the case of IgG antibodies, the immunoblot (Hauser: P=0.013;Engstr?m: P=0.004) and the RECO-EIA (P=0.02), were more specific than the Abs-EIA. It is concluded that the immunoblot (evaluated according toHauser) and the RECO-EIA are both suitable as confirmatory assays in the serological diagnosis of neuroborreliosis. Monoclonal antibodies are mandatory tools in the evaluation of the immunoblot.     

Appendicitis followed by reactive arthritis in an HLA B27-positive man after infection withYersinia enterocolitica, diagnosed by serotype specific antibodies and antibodies toYersinia outer membrane proteins

Summary A case of appendicitis followed by reactive arthritis in an HLA B27-positive, 29-year-old man after infection withYersinia enterocolitica is reported. Infection withY. enterocolitica was diagnosed by determination of serotype specific antibodies and antibodies toYersinia outer membrane proteins. Bacteriological cultures from the appendix were not made. Although reactive arthritis is a well-known complication ofYersinia-associated enteric disease, there are only few reports of patients withY. enterocolitica pseudo-appendicitis complicated by arthritis during follow-up.     

Persistence of Yersinia enterocolitica in man

Summary Ten patients with chronicYersinia enterocolitica infections are described. The initial diagnosis was made by culture, significant agglutinin titres and indirect immunofluorescence (IF) on biopsies. During the chronic phase, culture and agglutinin titres were negative, but specific serum IgA and IgG antibodies reactive with at least two, i.e. the 36 kDa and the 46 kDa, virulence-associated released proteins were demonstrated in nine patients by immunoblot techniques. One patient had only IgG antibodies. The chronically elevated IgA production was the result of chronic stimulation of the gut-associated lymphoid tissue by virulent persistentYersinia antigen, which was identified by IF with O-specific antiserum and monospecific antiserum to the 46 kDa released protein in biopsies. VirulentYersinia bacilli were demonstrated in the intestinal mucosa and in the lymphoid tissue of the submucosa associated with macrophages in patients with chronic ileitis and arthritis, in granulomatous centres of lymph nodes in patients with chronic lymphadenopathy and in portal infiltrates in a patient with chronic hepatitis. Recognition of persistentYersinia infections may have therapeutic implications.

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Persistenz von Yersinia enterocolitica bei Menschen

Zusammenfassung Zehn Patienten mit chronischerYersinia enterocolitica-Infektion werden beschrieben. Die Anfangsdiagnose war mittels positiver Kulturen, signifikanter Agglutinationstiter und immunhistologischem (IF) Yersinia-Nachweis in menschlichem Biopsiematerial gestellt worden. Während der chronischen Phase waren Kultur und Agglutinationstiter negativ, aber im Serum von neun Patienten waren mit Immunoblot spezifische IgA- und IgG-Antikörper gegen mindestens zwei, d. h. die 36 kDa und 46 kDa Virulenz-assoziierten Proteine nachzuweisen. Ein Patient hatte nur IgG-Antikörper. Die chronisch erhöhte IgA-Produktion war verursacht durch chronische Stimulierung des intestinalen lymphatischen Gewebes durch virulente, persistierendeYersinia-Antigene, die mittels IF mit O-spezifischem Antiserum und monospezifischem Antiserum gegen das 46 kDa Virulenz-Protein in Biopsiematerial identifiziert werden konnten. VirulenteYersinia-Bazillen lagen in Biopsien von Patienten mit chronischer Ileitis und Arthritis tief in der Darmmukosa und im lymphoiden Gewebe der Submukosa, assoziiert mit Makrophagen. Sie wurden auch in Lymphknoten von Patienten mit chronischer Lymph-adenopathie nachgewiesen und in portalen Infiltraten eines Patienten mit chronischer Hepatitis. Der Nachweis persistierenderYersinia-Infektionen kann therapeutische Konsequenzen haben.

     

IgA1 protease production by bacteria colonizing the upper respiratory tract

Summary Thirty-eight clinical isolates ofHaemophilus influenzae and ten clinical isolates ofStreptococcus pneumoniae were examined for IgA1 protease production. A suspension of surface material of each individual strain was incubated with human secretory IgA; IgA1 cleavage products were detected by SDS-PAGE and immunoblotting. The high incidence of IgA1 protease-positive strains (68.4% of the examinedH. influenzae and 100% of the examinedS. pneumoniae strains) confirms that IgA1 protease activity is a frequent characteristic of these two species. Yet the presence of this enzyme is, if at all, only a minor decisive factor for the induction of symptomatic infections of the upper respiratory tract by IgA1 protease-positive bacteria.     

Antibodies to ubiquitin in relation to <Emphasis Type="Italic">Yersinia</Emphasis> infection status in patients with ankylosing spondylitis

 The aim of this study was to investigate IgG and IgM antibodies to ubiquitin in relation to Yersinia enterocolitica infection status in patients with AS. Twenty-eight AS patients (M:F 24:4, mean age 43.9 yrs, range 22–70 yrs, mean disease duration 15.9 yrs) and 35 healthy controls (M:F 31:4, mean age 52.1 yrs, range 22–80 yrs) were included. The levels of antibodies to ubiquitin and Yersinia O:3 and O:9 antigens were measured using specific ELISA. The results were expressed as optical density (OD) ratio. Antibody levels were assumed increased when the OD ratio was higher than mean OD ratio + 3SD in the control group. IgM antibodies to ubiquitin were found in five patients and one control (P < 0.05, Fisher's exact test). Anti-ubiquitin antibodies of IgG class were found in two cases, one AS patient and one control (NS). IgG antibodies to Yersinia serotypes O:3 and O:9 were present in eight and five AS patients, respectively (P < 0.001 and P < 0.05 vs. controls, Fisher's exact test). No IgM antibodies to Yersinia were found. High levels of IgG antibodies to Y. enterocolitica serotype O:3 were found in three out of five patients with high levels of IgM antibodies to ubiquitin, compared with five out of 23 patients with low levels of anti-ubiquitin antibodies (P=0.1231, NS). Antibodies to Yersinia serotype O:9 were found in three out of five patients with IgM antibodies to ubiquitin, compared to two out of 23 patients with low serum levels of IgM antibodies to ubiquitin (P < 0.05). The results suggest that Y. enterocolitica infection may induce antibodies to ubiquitin in a subset of patients with AS. This may be explained by the involvement of a newly discovered ubiquitin-dependent mechanism related to Y. enterocolitica virulence. Received: 8 April 2002 / Accepted: 26 August 2002     

Disease-associated anti-bovine serum albumin antibodies in Type 1 (insulin-dependent) diabetes mellitus are detected by particle concentration fluoroimmunoassay,and not by enzyme linked immunoassay

Summary We recently developed a particle concentration fluoroimmunoassay for the measurement of serum antibodies to bovine serum albumin in patients with Type 1 (insulin-dependent) diabetes mellitus. We observed elevated IgG-anti-bovine serum albumin antibodies in 100% of newly-diagnosed diabetic children and in 2.5% of matched control children. Here we compare the fluoroimmunoassay and the more commonly available enzyme linked immunoassay technique, exchanging coded serum samples from 40 newly-diagnosed diabetic children and 179 control children between two laboratories. Particle concentration fluoroimmunoassay detected elevated IgG-anti-bovine serum albumin antibodies in all diabetic children, enzyme immunoassay in 25% (p <0.0001). Fluoroimmunoassay detected elevated levels in 2.2% and enzyme immunoassay in 10% of control children (p <0.002). Elevated IgA-antibovine serum albumin antibodies in patients were slightly more often detected by fluoroimmunoassay than by enzyme immunoassay, while in control children enzyme immunoassays detected elevated levels three times more often (p <0.01). Values measured in either assay showed overall no correlation in either patient (IgG: r_s = 0.28; IgA: r_s = 0.11) or control sera (IgG: r_s = 0.02; IgA: r_s = -0.05). Fluoroimmunoassay for IgG was 100% disease-sensitive (enzyme immu-noassay: 25%, p <0.0001) and more disease-specific (IgG; p <0.02). Our findings demonstrate that these assay techniques detected distinct subsets of anti-bovine serum albumin antibodies with little (IgG) or some (IgA) overlap. In fluoroimmunoassay procedures, antigen: antibody binding occurs within 1–2 min while hours are allowed in an enzyme immunoassay. Antibodies with high on-off binding rates typical for immune responses following hyperimmunization are therefore measured preferentially by particle concentration fluoroimmunoassay and it is these antibodies which appear to be associated with diabetes. These observations emphasize the need for epidemiological surveys to validate immunoassay procedures used for clinical purposes.     

Epidemiological study ofCryptosporidium parvum in sera of persons from Germany

Summary In a seroprevalence study including 495 sera from persons of all age-groups, the presence of anti-Cryptosporidium parvum antibodies was evaluated in an enzyme immunoassay. Despite the fact thatC. parvum is only found in approximately 2% of patients with diarrhea in Germany, specific antibodies could be detected in 15.4% of all samples. This figure indicates that a substantial proportion of the German population has been confronted with this parasite and it raises the question of whetherC. parvum is a potential health risk to the general population. An erratum to this article is available at .     

Relevance of Adjusted Cut-off Values in Commercial Serological Immunoassays for Helicobacter pylori Infection in Children

We assessed the sensitivity and specificity of H. pylori IgG and IgA with a commercial immunoassay performed in Chile and a second non-commercial immunoassay performed in a reference laboratory in the United States, in serum of 80 children and adults referred for gastrointestinal endoscopies in a developing country. Overall, 56% of the patients were infected with H. pylori based on rapid urease test and staining techniques on gastric biopsies. When Receiver Operator Curves (ROC) were developed, the sensitivity and specificity were similar for IgG and IgA. Both immunoassays exhibited better specificity, positive and negative predictive value (NPV) in children than in adults when cut-off values were corrected according to the local population than when they were assessed using the cut-off values pre-defined in other populations. These results underline the need to establish more precise cut-off values corrected in the local populations where assessments of antibodies as diagnostic markers of H. pylori infection are planning.     

Effects of Chelators (Deferoxamine,Deferiprone and Deferasirox) on the Growth of Klebsiella Pneumoniae and Aeromonas Hydrophila Isolated from Transfusion-Dependent Thalassemia Patients

Infections are among the leading causes of death for thalassemia major patients. The known predisposing factors of infection include prior splenectomy, iron overload and use of iron chelator such as deferoxamine (DFO). While encapsulated organisms frequently found in splenectomized patients were readily controlled by prophylactic vaccination and vigilant antibiotic treatment, ferrophilic organisms such as Yersinia and Klebsiella remain common pathogens in thalassemic patients. Yersinia infections are more prevalent in temperate regions and Klebsiella infections are commonly found in tropical and subtropical areas. While the use of DFO further aggravates the risk of Yersinia infection, oral chelators such as deferiprone (L1) do not enhance the growth of Yersinia in vitro or in vivo. We found that the growth of Klebsiella was marginally enhanced by DFO in vitro when compared to Yersinia. Such an unfavorable effect was not found in either L1 or deferasirox (DFRA) in vitro. The growth of Aeromonas was not affected by the presence of all three forms of chelators. Therefore, we suggest that factors other than DFO may account for the increased prevalence of Klebsiella and Aeromonas infection in Asian thalassemic patients.     

Immunoglobulin M antibodies are not specific for serodiagnosis of human toxocariasis

Serodiagnosis of human toxocariasis is established by detecting serum anti‐Toxocara IgG antibodies, but there is little knowledge regarding the reactivity of human IgM antibodies against the Toxocara antigens. In this study, we have evaluated the reactivity of IgM antibodies in sera from patients with toxocariasis, patients with other helminth infections, and healthy individuals, against Toxocara larval excretory‐secretory (TES) antigens by enzyme‐linked immunosorbent assay (ELISA) and Western blot (WB). Anti‐Toxocara IgM were detected in 91.4% of sera from patients with toxocariasis, 76% of sera from patients with other helminth infections, and 45.3% of sera from healthy individuals when ELISA was used. Likewise, IgM antibodies were detected in 94.8% of sera from patients with toxocariasis, 65.3% of sera from patients with other helminth infections, and 41% of sera from healthy individuals when WB was used. This reactivity exhibited only a slight decrease when the TES antigens were deglycosylated, showing that not only glycosidic epitopes, but also peptide epitopes are involved in the recognition and binding of IgM antibodies during the immune response against the parasite. The results shown that IgM antibodies are not specific for serodiagnosis of human toxocariasis.     

Clinical features of patients with novel Yersinia species

Our purpose was to describe the clinical features of patients with novel Yersinia species. Between 1985 and 1999; 194 patients had yersinia species isolated from stool specimens, 38 (20%) had non-Yersinia enterocolitica species; 12 (32%) had Yersinia intermedia, 7 (18%) Yersinia fredericksenii, 3 (8%) Yersinia kristensenii, and the remaining 16 (42%) were unclassified non-Yersinia enterocolitica species. The most common presenting symptom was diarrhea alone in 10 (26.3%) patients. Symptoms persisted for >1 month in 54% of cases; 21% had symptoms for <1 week; 18 (47%) patients were taking corticosteroids, acid suppressants, and/or antibiotics when Yersinia was isolated. An immunocompromised state was present in 11 (29%) patients. An immunocompromised host and administration of acid suppressants predicted persistence of symptoms for >1 month. Most [27 (71%)] patients received no treatment; 5 (13%) received antibiotics. In conclusion, novel non-Yersinia enterocolitica species, including Yersinia intermedia, Y. fredericksenii, and Y. kristensenii may represent up to 20% of all Yersinia isolates. Diarrhea is the most common symptom.     

Human glutathione S-transferase A1, T1, M1, and P1 polymorphisms and susceptibility to prostate cancer in the Japanese population

Purpose: The incidence of prostate cancer is increasing in low-risk populations such as Japanese. One of the causes of this increase is considered to be associated with the Western diet, especially the high intake of red meat and fat. Glutathione S-transferase (GST) A1, T1, M1, and P1 are phase II enzymes that are important for activation and detoxification of chemical carcinogens.Methods: In this study, 190 Japanese male patients with prostate cancer and 294 healthy controls, frequency-matched for age, were compared for frequencies of GSTA1, GSTT1, GSTM1, and GSTP1 genotypes.Results: Among smokers, the frequency of the GSTA1*A/*B or *B/*B genotype in patients with prostate cancer (27.8%) showed a statistically significant increase compared with the control group frequency (18.2%; odds ratio [OR] =1.72; 95% CI, 1.01–2.94). In addition, the frequency of GSTT1 nondeletion genotype was associated with prostate cancer among smokers (OR =1.68; 95% CI, 1.06–2.68). The OR of carrying the combined genotyping of GSTA1*A/*B or *B/*B and GSTT1 nondeletion was 2.08 (95% CI, 1.14–3.80) with the combined genotyping of GSTA1*A/*A and GSTT1 null as a reference. On the other hand, no significant associations were observed for genotypes of GSTM1 and GSTP1 I105V.Conclusions: These findings suggest that the GSTA1 and GSTT1 polymorphisms are associated with prostate cancer susceptibility, especially among smokers.     

Correlation between histopathological findings of the liver and IgA class antibodies to 2-oxo-acid dehydrogenase complex in primary biliary cirrhosis

Although anti-mitochondrial antibody (AMA) is the characteristic serological feature of primary biliary cirrhosis (PBC), its pathogenetic role remains unclear. We tested sera from 72 Japanese patients with histologically confirmed PBC for AMA by indirect immunofluorescence, anti-pyruvate dehydrogenase complex (PDC) by enzyme inhibition assay, immunoglobulin (Ig) G class anti-PDC by ELISA, and IgG, IgM, and IgA class anti-2-oxo-acid dehydrogenase complex (2-OADC) by immunoblotting. Of the 72 sera, 60 (83%), 50 (69%), 42 (58%), and 71 (99%) were positive for AMA by immunofluorescence, enzyme inhibition assay, ELISA, and immunoblotting, respectively. There was no significant correlation between histological stages and AMA by immunofluorescence, PDC inhibitory antibodies by enzyme inhibition assay, IgG class anti-PDC antibodies by ELISA, or IgG and IgM class anti-2-OADC by immunoblotting. IgA class anti-2-OADC by immunoblotting was more frequent in stages 2–4 than in stage 1 (P = 0.0083). Of the IgA class anti-2-OADC, anti-PDC-E2 (74 kDa) and anti-E3BP (52 kDa) were more frequent in stages 2–4 than in stage 1 (P = 0.0253 and 0.0042, respectively). Further examination of histopathological findings in 53 of 72 liver biopsy specimens showed that IgA class anti-PDC-E2 and IgA class anti-E3BP were associated with bile duct loss, and IgA class anti-PDC-E2 was also associated with interface hepatitis and atypical ductular proliferation. IgA is known to be secreted into the bile through biliary epithelial cells, implying that IgA class anti-PDC-E2 and E3BP may have a specific pathogenetic role during their transport into the bile by binding to their target antigen(s) in biliary epithelial cells, and this may be followed by dysfunction and finally destruction of biliary epithelial cells. Our present results suggest that these autoantibodies against 2-OADC detected by immunoblotting may be associated with the pathogenesis and pathologic progression of PBC.     

Antibody to hepatitis C virus in risk groups in Canada

The prevalence of antibodies against hepatitis C virus (HCV) was studied in hemophiliacs, hemodialysis patients, intravenous drug abusers, female prisoners, homosexuals, individuals with no markers of recent hepatitis A or B virus infections and normal individuals (federal public servants), by an enzyme immunoassay (Ortho Diagnostic Systems Inc). Repeat positive samples were further tested by recombinant immunoblot assay (riba) HCV (Chiron Corp, California). The number of samples positive for antibodies to HCV (anti-HCV) was higher with enzyme immunoassay than by riba HCV in most cases. A high prevalence of anti-HCV was detected in hemophiliacs by both enzyme immunoassay (68.8%) and riba HCV (53.7%). Among intravenous drug abusers and female prisoners the prevalence rates for anti-HCV were 42.8% and 29.8%, respectively, by riba HCV; the results with enzyme immunoassay were only slightly higher. The prevalence rate was also high by both tests (54.2%) in hemodialysis patients' sera taken during 1980-82, when many cases of non-A,non-B hepatitis were suspected in this group. In contrast, only 14.1% of sera taken during 1990 were positive by riba HCV. In individuals with no markers of recent hepatitis A or B infections, 13.4% were positive by enzyme immunoassay, whereas only 4.5% were reactive by riba HCV. The lowest prevalence was seen in homosexuals (2.3%) and normal individuals (1.2%) by riba HCV. These results indicate a high prevalence of anti-HCV in high risk groups tested in Canada.     

Antibodies to type II collagen and their association with HLA DR1 alleles in Japanese patients with rheumatoid arthritis

 To investigate whether immunological responses to type II collagen (CII) play an important role in the pathogenesis of rheumatoid arthritis (RA), the presence of anti-CII antibodies was examined by enzyme immunoassay in 130 Japanese patients with RA, 10 systemic lupus erythematosus (SLE) patients, and 30 healthy subjects. In addition, the HLA-DRB1 genes of 40 RA patients were determined, and their association with positive findings of anti-CII antibodies was examined. A significantly high frequency of positive findings of anti-CII antibodies was detected in sera from RA patients (19%, P < 0.05) in comparison with that in sera from healthy subjects (3%). High frequencies of DRB1^*0405 and 0101 alleles were observed in the 40 RA patients examined (40.0% and 30.0%, respectively). Patients with DRB1^*0101 had a significantly higher rate of positive findings of anti-CII antibodies than those without DRB1^*0101 (66.7% and 28.6%, respectively, P < 0.05). No such association was observed for DRB1^*0405. From these findings, we suggest that immunological responses to CII may play an important role in the development of arthritis in some RA patients. Received: April 9, 2002 / Accepted: June 13, 2002 Acknowledgment We thank Dr. T. Sakamaki, Division of Clinical Research, Sakura National Hospital, Japan, for technical assistance and useful advices on HLA typing. Correspondence to:T. Sumida     

EsophagealCandida infection and adherence mechanisms in the nonimmunocompromised rabbit

Candida infection of the esophagus has been reported not only in immunocompromised hosts but also in healthy individuals. However, its mechanisms of action in healthy individuals have not been clarified. Our previous study suggested that physical contact was an important factor for the adherence ofCandida albicans. The aim of the present study was to test our hypothesis and clarify the adherence mechanisms. Suspensions ofCandida albicans cells were given to rabbits in drinking water without the use of immunosuppressive drugs and/or antibiotics, and the esophagus was examined. Candidial lesions were observed in 14 of 15 rabbits given the suspensions held in water with and without 30% sucrose for 13 days. The number ofCandida albicans cells adhering to the esophagus per square millimeter by subepithelial cell insertion was significantly larger than that adhering by attachment. These results indicate that adherence ofCandida albicans to the esophagus occurs by sustained physical contact alone under a nonimmunosuppressive state, and that subepithelial cell insertion results in greater attachment on adherence. Our findings provide a clue that may help clarify the mechanism ofCandida infection in healthy individuals. Parts of this study were presented at the 78th General Meeting of the Japanese Society of Gastroenterology (Tokyo, 1992) and at the 79th General Meeting of the Japanese Society of Gastroenterology (Kyoto, 1993).     

Enzyme immunoassay for antibodies to native DNA

An enzyme immunoassay was developed to detect antibodies to native DNA; DNA coating conditions that maximized sensitivity, specificity, and reproducibility were selected. Sera of patients with systemic lupus erythematosus (SLE) were positive more frequently by this immunoassay than by the Crithidia luciliae assay or by counterimmunoelectrophoresis. By enzyme immunoassay, 94% of sera with active SLE and 70% of sera from patients with inactive SLE were positive, as were 16% from those suspected of having SLE, and 2.5% of normal persons. Specificity for native DNA was shown for both SLE and normal sera by inhibition studies and by S1 nuclease treatment of polystyrene-bound native DNA. The enzyme immunoassay correlated more with serum hemolytic complement levels than did the other 2 assays, suggesting that it detects biologically more relevant anti-DNA antibodies than do the other 2 tests.