Rheumatoid Arthritis: Kiss R

Steinfeld SD, Demols P, Salmon I, Kiss R, Appelboom T. · Department of Rheumatology, Erasme University Hospital, Université Libre de Bruxelles, Brussels, Belgium. · Arthritis Rheum. · Pubmed #11665979 No free full text.

Abstract: OBJECTIVE: Tumor necrosis factor alpha (TNFalpha) is a proinflammatory cytokine involved in the pathogenesis of Sjögren's syndrome (SS), and blockade of TNFalpha may reduce the activity of the disease. The purpose of this study was to evaluate the safety and potential efficacy of infliximab, a chimeric human-mouse anti-TNFalpha monoclonal antibody, in patients with active primary SS. METHODS: This was a single-center, open-label pilot study. Sixteen patients with active primary SS received 3 infusions of infliximab (3 mg/kg) at 0, 2, and 6 weeks. Standard clinical assessment, complete ophthalmologic testing, and functional evaluation of salivary flow were performed at baseline and at weeks 2, 6, 10, and 14. RESULTS: All patients completed the study. There was statistically significant improvement in all clinical and functional parameters, including global assessments (patient's global assessment, patient's assessment of pain and fatigue, physician's global assessment), erythrocyte sedimentation rate, salivary flow rate, the Schirmer I test, tender joint count, fatigue score, and dry eyes and dry mouth. This clinical benefit was observed at week 2 and was maintained throughout the study and the 2-month followup period. The treatment was well tolerated in all patients, and no significant adverse events were seen. No lupus-like syndrome was observed, and no anti-double-stranded DNA antibodies were observed that were attributable to infliximab therapy. CONCLUSION: In patients with active primary SS, a loading-dose regimen of 3 infusions of infliximab provided a fast and significant clinical benefit without major adverse reactions. It was possible to maintain statistically significant improvement for up to 8 weeks after the third infusion.

Steinfeld S, Cogan E, King LS, Agre P, Kiss R, Delporte C. · Division of Rheumatology, Erasme University Hospital, Brussels, Belgium. · Lab Invest. · Pubmed #11232635 No free full text.

Abstract: Patients with Sjögren's syndrome (SS) suffer from deficient secretion of saliva due to an autoimmune destruction of salivary glands, however, glandular dysfunction also occurs without destruction. Based upon its abnormal distribution in SS salivary glands, a potential role for the water channel protein aquaporin-5 (AQP5) is proposed in the pathogenesis of SS. The immunohistochemical distribution of AQP5 was compared in minor salivary gland biopsies obtained from women after informed consent: primary SS (53.2 +/- 14 years old, n = 10), healthy volunteers (46.2 +/- 17 years old, n = 10), patients with sarcoidosis (37 and 48 years old), and patients with non-specific sialoadenitis (54 and 61 years old). Biopsies from normal subjects revealed AQP5 primarily at the apical membrane of the salivary gland acinus. In contrast, biopsies from SS patients revealed AQP5 primarily at the basal membranes of the acinus. The AQP5 distribution in biopsies from patients with other dry mouth disorders, such as non-specific sialoadenitis or sarcoidosis, was similar to biopsies from control subjects. Computer-assisted microscopy was performed to quantitatively evaluate AQP5 distribution in the immunoreactive acini of both SS and control subjects. Biopsies from SS patients had higher labeling indices (percentage of acinus area immunoreactive for AQP5) at the basal membrane when compared with biopsies from control subjects. In contrast, biopsies of SS patients exhibited lower labeling indices at the apical membrane when compared with biopsies from control subjects. To verify the specificity of the AQP5 antibody, Western blot analysis was performed on membranes from Xenopus oocytes injected with AQP5 cRNA or on membranes from minor salivary glands of control subjects and SS patients. In each case, the immunoblots had a 27 kd band, corresponding to the expected molecular weight of AQP5. Abnormal distribution of AQP5 in salivary gland acini is likely to contribute to the deficiency of fluid secretion, which is a defining feature of Sjögren's syndrome.

Steinfeld S, Maho A, Chaboteaux C, Daelemans P, Pochet R, Appelboom T, Kiss R. · Divisions of Rheumatology, Erasme University Hospital, Brussels, Belgium. · Lab Invest. · Pubmed #11092531 No free full text.

Abstract: Various proteases are expressed in the minor salivary glands (MSG) of patients with Sjögren's syndrome (SS), and as we have already shown, prolactin is neosynthesized in the acinar cells of patients with SS. The present study aims to characterize the influence of PRL on the expression of cathepsin B and D in the MSG of patients with SS. Cathepsin B and D expression was investigated immunohistochemically in MSG of 30 patients with SS and 15 healthy volunteers. The presence of cathepsin B and D mRNAs was checked in three SS patients and three control subjects by means of reverse transcription-polymerase chain reaction (RT-PCR). The specificity of the anti-cathepsin B and D antibodies used for the immunohistochemistry was checked by means of western blotting analysis. The influence of prolactin on the immunohistochemical expression of cathepsin B and D was quantitatively assayed by computer-assisted microscopy at three different doses (5, 50, and 500 ng/ml) on eight MSGs (four control subjects and four patients with SS) maintained ex vivo under organotypic cultures. This influence was also investigated at the mRNA level. Whereas cathepsin B immunopositivity was absent from glandular epithelial cells of healthy subjects and only slightly present in SS patients, cathepsin D immunoreactivity was considerably greater (p < 0.0001) in both the acini and the ducts of patients with SS as compared with control subjects. Cathepsin B, but not D, was also expressed in about 20% of infiltrating mononuclear cells of SS patients. Treatment of both healthy and SS minor salivary glands with PRL significantly (p < 0.05 top < 0.0001) enhanced cathepsin B and D expression in acinar and ductal cells at both protein and mRNA levels. PRL produced locally in MSGs of SS patients, but not those of healthy subjects, could play a role in the pathogenesis of Sjogren's syndrome, if only through the activation of proteolytic activity on the part of cathepsins B and D.

Steinfeld S, Penaloza A, Decaestecker C, Rommes S, André S, Schüring MP, Danguy A, Appelboom T, Kiss R, Gabius HJ. · Department of Rheumatology, Erasmus Academic Hospital, Brussels, Belgium. · J Rheumatol. · Pubmed #10955332 No free full text.

Abstract: OBJECTIVE: The profile of glycans and their recognition by endogenous receptors (lectins) are increasingly attributed to disease process. Monitoring this can provide information on the pathogenesis of Sjögren's syndrome (SS). Commonly, plant lectins are employed for phenomenological glycan mapping. To go beyond this approach restricted to binding of exogenous probes, new markers measure ligand properties of glycans to human (not plant) lectins and the presence of sugar receptors completing a protein-carbohydrate recognition system. Carrier-immobilized sugar epitopes (neoglycoproteins) and purified human lectins establish this innovative panel. METHODS: The host defence molecules mannan binding lectin, serum amyloid P component, and the macrophage migration inhibitory factor-binding sarcolectin, selected for their involvement in cell destructive mechanisms, were purified and labeled. The plant lectins SNA and MAA were employed to monitor regulation of potential ligand sites for I-type lectins and galectins. Asialofetuin was tested as a "pan-galectin selective" probe. The specific binding characteristics were determined by quantitative morphometry and statistical analysis. RESULTS: Diagnostic information emerged from this analysis. The percentage of stained tissue area was significantly different between SS and control specimens after processing with GlcNAc and Man-bearing neoglycoproteins and the 2 tested serum lectins. For separation of cases of primary and secondary SS, the staining intensity with the asialoglycoprotein, sarcolectin, and the exogenous alpha2,6-sialylated glycan-binding lectin SNA was statistically significant. CONCLUSION: Saccharide-presenting probes to measure the cellular capacity to bind glycan epitopes and human lectins as sensors for endogenous binding sites have proven to be useful as diagnostic tools. We suggest the differences we observed reflect aberrations from the normal cellular homeostasis with relevance for the pathogenesis of SS and its manifestation as a primary or secondary syndrome.

Steinfeld S, Rommes S, François C, Decaestecker C, Maho A, Appelboom T, Heizmann CW, Kiss R, Pochet R. · Division of Rheumatology, Erasme University Hospital, Brussels, Belgium. · Lab Invest. · Pubmed #10701693 No free full text.

Abstract: Characterization of endogenous synthesis of prolactin (PRL) proteins and their cellular localization in labial salivary glands of patients with Sjogren's syndrome (SS) were achieved. PRL, PRL-receptors (PRL-R), and S100A6 protein were detected by immunohistochemistry. In situ prolactin synthesis was investigated in controls and SS patients by ex vivo incubation of minor salivary glands biopsies and immunoprecipitation assay. Increased PRL-immunoreactivity was found in cytoplasmic acinar epithelial cells in SS patients compared with normal subjects. PRL-R was distributed only in ductal epithelial cells in which S100A6 protein (a PRL-R-associated protein) was also present. PRL, PRL-R, or S100A6-immunoreactivity was not detected in infiltrating mononuclear cells. Immunoprecipitation demonstrated that PRL synthesis occurred in minor salivary glands with increased synthesis of two distinct PRL-like proteins (one major band at 60 kDa and a minor at 16 kDa) in SS glands compared with normal glands. Expression of PRL gene was demonstrated in SS salivary glands using RT-PCR. A positive correlation was found between the presence of PRL-like proteins in acinar epithelial cells of SS patients and clinical extraglandular manifestations. The presence of anti-Ro and anti-La antibodies also positively correlated with a higher percentage of PRL in acinar epithelial cells. In conclusion, PRL-like proteins are synthetized and overexpressed in glandular epithelial cells of labial salivary glands from SS patients and correlate with the aggressiveness of the disease.

Penaloza A, Decaestecker C, Ribaï P, Nagy N, Salmon I, Appelboom T, Danguy A, Kiss R, Steinfeld S. · Laboratory of Histology, Faculty of Medicine, Université Libre de Bruxelles, Belgium. · Clin Exp Rheumatol. · Pubmed #10609070 No free full text.

Abstract: OBJECTIVE: To investigate the composition and expression of sialic acid in the labial salivary glands (LSG) in Sjögren's syndrome (SS). METHODS: LSG of 19 patients with primary SS (n = 11) or secondary SS (n = 8) were studied. Specimens from 7 healthy women served as controls. Computer-assisted microscopy was employed to quantitatively determine the percentage of positive structures, the staining intensity and the heterogeneity for the 4 biotinylated plant lectins Tritricum vulgaris L. (WGA), Maackia amurensis (MAA), Sambucus nigra (SNA) and Canavalia ensiformis L. (Con A). RESULTS: In the acini there was a significant decrease in the staining heterogeneity of WGA in SS compared to controls; the same was observed with respect to MAA staining in the connective tissue and extralobular ducts. In the intralobular ducts, primary SS differed from normal and secondary SS mainly in terms of a decrease in the percentage of positively labeled MAA tissue. In addition, Con A stained acinar cells were significantly more numerous in secondary SS compared with primary SS. CONCLUSION: Differences in the degree of glycoconjugate sialylation were found in SS labial salivary glands, and may play a role in the disease process.

Steinfeld S, Penaloza A, Ribaï P, Decaestecker C, Danguy A, Gabius HJ, Salmon I, Appelboom T, Kiss R. · Department of Rheumatology, Erasmus Academic Hospital, Brussels, Belgium. · J Rheumatol. · Pubmed #10229404 No free full text.

Abstract: OBJECTIVE: Sjögren's syndrome (SS) is an autoimmune exocrinopathy. The mannose binding lectin (MBL), a pluripotent molecule of the innate immune system, is involved in the pathogenesis of autoimmune diseases. We investigated whether specific ligands for MBL and MBL related structures could be reliable markers in cases of SS. METHODS: The labial salivary glands of 19 patients fulfilling the diagnostic criteria for primary (n=11) and secondary SS (n=8) were studied. Seven healthy women served as controls. Computer assisted microscopy was employed to determine quantitatively the percentage of positive structures (acini, ducts, and interlobular connective tissue), the staining intensity, and the level of staining heterogeneity for 4 glycohistochemical probes including wheat germ agglutinin and concanavalin (Con A) as lectins, and mannose and N-acetylglucosamine as parts of neoglycoproteins. The data were evaluated by discriminant analysis. RESULTS: The data strongly suggest that MBL related structures, if not MBL itself, could play distinct roles in the pathogenesis of primary versus secondary SS. Further, quantitative determination of the level of expression of D-mannose and N-acetylglucosamine and their respective binding sites in labial salivary gland acini offers a powerful diagnostic tool for distinguishing primary from secondary SS. CONCLUSION: In SS labial salivary glands, determination of the level of acceptor sites for wheat germ agglutinin, Con A, D-mannose, and N-acetylglucosamine provides information on the roles played by glycoforms in SS. The methodology and data described in this paper should provide pathologists with objective diagnostic markers for SS. Our results should enhance the biological understanding of this pathology.