Evidence for differential effects of sulphasalazine on systemic and mucosal immunity in rheumatoid arthritis

In rheumatoid arthritis patients, total IgA1 and IgA2 levels are elevated: implications for the mucosal origin hypothesis

OBJECTIVE

Mucosal initiated immune responses may be involved in the pathophysiology of RA. The most abundant immunoglobulin at mucosal surfaces is IgA, of which two subclasses exist: IgA1 and IgA2. IgA2 is mainly present at mucosal sites and has been ascribed pro-inflammatory properties. As IgA subclasses might provide insights into mucosal involvement and pro-inflammatory mechanisms, we investigated IgA responses in sera of RA patients.

METHODS

In two cohorts of RA patients, the EAC and IMPROVED, total IgA1 and IgA2 were measured by ELISA. Furthermore, IgA subclass levels of RF and anti-citrullinated protein antibodies (anti-CCP2) were determined. The association of these IgA subclass levels with CRP and smoking was investigated.

RESULTS

Total IgA1 and IgA2 were increased in RA patients compared with healthy donors in both cohorts. This increase was more pronounced in seropositive RA vs seronegative RA. For RF and anti-CCP2, both IgA1 and IgA2 could be detected. No strong associations were found between IgA subclasses (total, RF and anti-CCP2) and CRP. In smoking RA patients, a trend towards a selective increase in total IgA2 and RF IgA1 and IgA2 was observed.

CONCLUSION

RA patients have raised IgA1 and IgA2 levels. No shift towards IgA2 was observed, indicating that the increase in total IgA is not due to translocation of mucosal IgA into the bloodstream. However, mucosal inflammation might play a role, given the association between smoking and total IgA2 levels. Despite its pro-inflammatory properties, IgA2 does not associate strongly with pro-inflammatory markers in RA patients.

Ageratina adenophora Disrupts the Intestinal Structure and Immune Barrier Integrity in Rats

The aim of this study was to investigate the effects of Ageratina adenophora on the intestines morphology and integrity in rat. Rats were randomly divided into two groups and were fed with 10 g/100 g body weight (BW) basal diet and 10 g/100 g BW experimental diet, which was a mixture of A. adenophora powder and basal diet in a 3:7 ratio. The feeding experiment lasted for 60 days. At days 28 and 60 of the experiment, eight rats/group/timepoint were randomly selected, weighed, and sacrificed, then blood and intestinal tissues were collected and stored for further analysis. The results showed that Ageratina adenophora caused pathological changes and injury in the intestine, elevated serum diamine oxidase (DAO), D-lactate (D-LA), and secretory immunoglobulin A (sIgA) levels, reduced occludin levels in intestinal tissues, as well as increased the count of intraepithelial leukocytes (IELs) and lamina propria leukocytes (LPLs) in the intestine (p < 0.05 or p < 0.01). In addition, the mRNA and protein (ELISA) expressions of pro-inflammation cytokines (IL-1β, IL-2, TNF-α, and IFN-ϒ) were elevated in the Ageratina adenophora treatment groups, whereas anti-inflammatory cytokines such as IL-4 and IL-10 were reduced (p < 0.01 or p < 0.05). Therefore, the results obtained in this study indicated that Ageratina adenophora impaired intestinal function in rats by damaging the intestine structure and integrity, and also triggered an inflammation immune response that led to intestinal immune barrier dysfunction.

Antibody responses after documented COVID-19 disease in patients with autoimmune rheumatic disease

Patients with autoimmune rheumatic diseases (AIRD) are suspected to have less robust immune responses during COVID-19 due to underlying immune dysfunction and the use of immune-suppressive drugs. Fifty consecutive patients with a diagnosis of AIRD on disease-modifying drugs were included at around 30 days after a confirmatory test for COVID-19. Fifty controls matched one to one for age, sex, and severity of COVID-19 were also included at around 30 days after testing positive for COVID-19. Antibody titers for anti-spike protein IgG and anti-nucleocapsid protein IgG were estimated. Cases (mean age 45.9 ± 13; 76% females) and controls (mean age 45.9 ± 13; 76% females) had similar proportion of comorbidities. Of the cases, 4 had moderate and 1 had severe COVID-19, while 3 and 1 of controls had moderate and severe COVID-19 respectively. Positivity of anti-N IgG was similar between patients (80%) and controls (90%) (p = 0.26). Similarly, anti-S IgG was positive in 82% of patients and 86% of controls (p = 0.79). Both the antibodies were negative in seven (14%) patients and five (10%) of controls (p = 0.76, Fischer exact test). Only anti-N IgG titers were lower in patients as compared to controls. In four patients with rheumatoid arthritis, two with spondyloarthritis and one with eosinophilic fasciitis both antibodies were not detectable. They did not differ from the rest of the cohort in clinical characteristics. The patients with AIRD had adequate protective antibody responses to COVID-19 at a median of 30 days post-infection. Thus, the presence of AIRD or the use of immunosuppressants does not seem to influence the development of humoral immune response against COVID-19.

Key Points • Patients with autoimmune rheumatic diseases (AIRD) are suspected to have less robust immune responses. • In our cohort of 50 patients with AIRD with confirmed COVID-19, only seven did not have detectable protective antibodies at 30 days post infection. • Patients with AIRD on immunosuppressants have adequate protective antibodies post COVID-19 disease, at rates similar to that in health controls.

Effects of biological and non-biological immunomodulatory therapies on the immunogenicity of vaccines in patients with rheumatic diseases

Vaccinations are administered to patients to induce a protective immune response, resulting in immunological memory. Preventing infection through the use of vaccines is particularly important in immunocompromised and immunosuppressed individuals given their increased frequency and severity of infections relative to healthy individuals. Recent surveys show that the vaccination rate is still alarmingly low in patients with rheumatic disease. In this review we briefly discuss the different types of vaccines and then critically examine evidence related to vaccination efficacy in patients with autoimmune disease and the effects of immunomodulatory therapy, with an aim to provide guidance and optimize the administration of vaccines in such individuals.

Gastrointestinal and hepatic manifestations of rheumatoid arthritis

Rheumatoid arthritis (RA), characterized by inflammation of the synovium and surrounding structures, has a prevalence of 0.5-1%. Rheumatoid vasculitis (RV) is an inflammatory condition of the small- and medium-sized vessels that affects up to 5% of patients with RA with intestinal involvement in 10-38% of these cases. Clinically apparent RV of the gastrointestinal (GI) tract, while rare, is often catastrophic, resulting in ischemic ulcers and bowel infarction. Vasculitis of the colon may present as pancolitis clinically similar to ulcerative colitis. Rectal biopsies that include submucosal vessels are positive for vasculitis in up to 40% of cases. Abnormal esophageal motility in RA may result in heartburn and dysphagia. Chronic atrophic gastritis may be associated with hypergastrinemia and hypo- or achlorhydria, promoting small bowel bacterial overgrowth. RA is the most common cause of secondary amyloidosis with GI symptoms in 22% of affected patients. Although amyloid is usually found in the liver, it is rarely evident clinically. Felty's syndrome occurs in less than 1% of patients with RA and is characterized by neutropenia and splenomegaly. The liver may be involved with portal fibrosis or nodular regenerative hyperplasia. Liver histology is abnormal in 92% of RA patients at autopsy, although the changes are usually mild without associated hepatomegaly. Drug-induced liver disease may occur with aspirin, sulfasalazine, and methotrexate. Significant liver damage is rare if the drug is discontinued or the patient is properly monitored. RA can affect both the GI tract and the liver; changes are usually mild except with RV.

The gut-joint axis: cross reactive food antibodies in rheumatoid arthritis

BACKGROUND AND AIMS

Patients with rheumatoid arthritis (RA) often feel there is an association between food intake and rheumatoid disease severity. To investigate a putative immunological link between gut immunity and RA, food antibodies were measured in serum and perfusion fluid from the jejunum of RA patients and healthy controls to determine the systemic and mucosal immune response.

METHODS

IgG, IgA, and IgM antibodies to dietary antigens were measured in serum and jejunal perfusion fluid from 14 RA patients and 20 healthy subjects. The antigens originated from cow's milk (alpha-lactalbumin, beta-lactoglobulin, casein), cereals, hen's egg (ovalbumin), cod fish, and pork meat.

RESULTS

In intestinal fluid of many RA patients, all three immunoglobulin classes showed increased food specific activities. Except for IgM activity against beta-lactoglobulin, all other IgM activities were significantly increased irrespective of the total IgM level. The RA associated serum IgM antibody responses were relatively much less pronounced. Compared with IgM, the intestinal IgA activities were less consistently raised, with no significant increase against gliadin and casein. Considerable cross reactivity of IgM and IgA antibodies was documented by absorption tests. Although intestinal IgG activity to food was quite low, it was nevertheless significantly increased against many antigens in RA patients. Three of the five RA patients treated with sulfasalazine for 16 weeks had initially raised levels of intestinal food antibodies; these became normalised after treatment, but clinical improvement was better reflected in a reduced erythrocyte sedimentation rate.

CONCLUSIONS

The production of cross reactive antibodies is strikingly increased in the gut of many RA patients. Their food related problems might reflect an adverse additive effect of multiple modest hypersensitivity reactions mediated, for instance, by immune complexes promoting autoimmune reactions in the joints.

Longitudinal analysis of citrullinated protein/peptide antibodies (anti-CP) during 5 year follow up in early rheumatoid arthritis: anti-CP status predicts worse disease activity and greater radiological progression

OBJECTIVE

To study serum levels of citrullinated protein/peptide antibodies (anti-CP) during up to 5 years' follow up of patients with early rheumatoid arthritis (RA), and to relate serum levels to disease course and to treatments in clinical practice.

METHODS

279 patients with early RA were followed up with clinical investigations, radiographs, and measurement of anti-CP at baseline and after 3 months, 1, 2, 3, and 5 years.

RESULTS

160/279 (57.3%) patients were anti-CP positive at the first visit (mean 5 months after first symptoms). During follow up only 11/279 (3.9%) of the patients changed their anti-CP status. Anti-CP levels fell significantly during the first year, and this drop correlated with the extent of sulfasalazine treatment but not with other drugs or clinical indices. Anti-CP positive and negative patients had similar disease activities at baseline, but during follow up the anti-CP positive patients had worse clinical disease and greater radiological progression, despite at least equally intensive antirheumatic treatment.

CONCLUSIONS

Anti-CP are stable during the first 5 years of RA, suggesting that events before rather than after onset of clinical manifestations of disease determine this phenotype. The presence of anti-CP at diagnosis predicts a less favourable disease course and greater radiological progression despite antirheumatic treatment, but subsequent changes in antibody levels do not reflect changes in disease activity. Taken together, these observations suggest that anti-CP positive RA is a distinct clinical and pathophysiological entity.

Anti-Saccharomyces cerevisiae antibodies: a stable marker for Crohn's disease during steroid and 5-aminosalicylic acid treatment

OBJECTIVES

An increased prevalence of elevated serum anti-Saccharomyces cerevisiae antibody (ASCA) levels in patients with Crohn's disease (CD) has been described. The aim of the present work was to investigate serum ASCA levels during the courses of prednisolone and mesalamine therapy in CD patients.

METHODS

Serum samples of 25 patients with active CD were studied for ASCA levels before as well as 2 and 9 wk after initiation of a prednisolone tapering regimen. The influence of mesalamine (4 g o.d.) on serum ASCA levels compared to that of placebo was tested over 1 yr in 38 patients (20 mesalamine and 18 placebo) participating in a postoperative prophylaxis study. Serum IgG and IgA ASCA levels were measured by ELISA. Sera of 91 CD and 40 ulcerative colitis (UC) patients as well as 334 healthy donors were tested for ASCA to recalculate new cut-off values.

RESULTS

For IgG ASCA cut-off values were determined to be 17.0 U and 25.0 U, and for IgA ASCA 9.3 U and 14.0 U. At baseline visit, 73.0% (46/63) of patients displayed serum ASCA positivity. During prednisolone therapy, a decrease in serum IgG and IgA ASCA levels from baseline to wk 2 (p < 0.0001 and p < 0.001, respectively) as well as to wk 9 (p < 0.001 and p = 0.01, respectively) was observed. A trend toward an association of ASCA positivity and steroid responsiveness was calculated (p = 0.07). During mesalamine treatment, no differences in changes of ASCA levels were observed compared to placebo at any time point.

CONCLUSIONS

ASCA are stable markers during steroid and mesalamine treatment, highlighting their reliability for use in diagnosis of CD.

Effects of sulfasalazine treatment on serum immunoglobulin levels in children with juvenile chronic arthritis

This article describes the effects of sulfasalazine (SSZ) treatment on serum immunoglobulin (Ig) levels in 6 children with oligoarticular- or polyarticular onset juvenile chronic arthritis (JCA). None of the children who developed dysimmunoglobulinemia during treatment showed clinical symptoms of this adverse event, in particular none developed severe infections. All patients regained normal immunoglobulin levels after discontinuing SSZ treatment. One patient with a partial IgA deficiency at the start of SSZ treatment showed a slow increase in the IgA level during treatment. During follow-up (4-6 years), one patient spontaneously developed a dysimmunoglobulinemia and one patient developed diabetes mellitus. Based on these case reports and review of the literature we advocate monitoring of serum immunoglobulin levels while on SSZ treatment.

Decreased anti-Saccharomyces cerevisiae antibody titer by mesalazine in patients with Crohn's disease

BACKGROUND

Saccharomyces cerevisiae may contribute to the pathophysiology of Crohn's disease. We determined serum anti-Saccharomyces cerevisiae antibody (ASCA) levels in patients with inflammatory bowel disease.

METHODS AND RESULTS

Immunoglobulin G (IgG) ASCA was measured by using an ELISA in serum samples from 19 patients with ulcerative colitis, 18 patients with Crohn's disease and 7 healthy controls. The ASCA level was significantly higher in patients with ulcerative colitis and patients with Crohn's disease than in controls, and was significantly higher in patients with Crohn's disease compared with patients with ulcerative colitis. Age, gender, disease activity, extent of disease and small bowel involvement each did not affect ASCA levels. The use of elemental or polymeric diet therapy for Crohn's disease and administration of corticosteroids to patients with inflammatory bowel disease also did not affect ASCA levels. The ASCA titer was significantly lower in patients with Crohn's disease taking mesalazine than in those not taking it, although, serum IgG levels did not differ between these two groups, which might imply a suppression of IgG production by mesalazine at the intestinal level.

CONCLUSIONS

The finding of increased serum ASCA titers in patients with inflammatory bowel disease suggests that Saccharomyces cerevisiae may play a role in the pathophysiology of this condition.

Development of lupus-related side-effects in patients with early RA during sulphasalazine treatment-the role of IL-10 and HLA

OBJECTIVE

The development of systemic lupus erythematosus (SLE)-related syndromes during treatment with sulphasalazine has been described and demonstrated to be influenced by genetic factors. The prevalence of this drug-induced condition and the immunological mechanisms involved are less known. The aim of this study was to determine the prevalence of sulphasalazine-induced lupus-like reactions in a well-defined early rheumatoid arthritis (RA) cohort and to analyse the roles of HLA haplotypes, autoantibodies and the B-cell stimulating cytokine interleukin-10 (IL-10) as possible underlying risk factors. Patients and methods. Forty-one consecutive patients with early RA, in whom sulphasalazine was used as the first disease-modifying anti-rheumatic drug in single therapy and was maintained for at least 6 months, were investigated for the occurrence of lupus-related events. Longitudinal analyses of rheumatoid factor (RF), antinuclear antibodies (ANA), anti-double-stranded DNA antibodies and serum IL-10 (ELISA) and the typing of HLA DR and DQ alleles were performed.

RESULTS

Four of the 41 patients developed lupus-like disease. Three of four patients who had lupus-related events vs four of 37 patients without side-effects had an HLA DR 0301 haplotype. The patients developing lupus-related side-effects had increased levels of serum IL-10 and a high frequency of ANA in speckled patterns before the onset of therapy.

CONCLUSION

The development of SLE-like symptoms and SLE-related autoantibody production was observed more commonly than expected, with an increased risk in patients with SLE-related HLA haplotypes, increased serum IL-10 levels and ANA in speckled patterns. The data suggest that immunomodulation associated with sulphasalazine treatment may contribute to the development of lupus-related reactions in genetically predisposed individuals.

Enhanced jejunal production of antibodies to Klebsiella and other Enterobacteria in patients with ankylosing spondylitis and rheumatoid arthritis

OBJECTIVE

To measure gut immunity directly in jejunal fluid in patients with ankylosing spondylitis (AS) and rheumatoid arthritis (RA).

METHODS

Antibodies against three different Enterobacterias were measured in jejunal perfusion fluids (collected by a double balloon perfusion device) of 19 patients with AS, 14 patients with RA, and 22 healthy controls using enzyme linked immunosorbent assay.

RESULTS

The AS patients had significantly increased jejunal fluid concentrations of IgM, IgG, and IgA class antibodies against Klebsiella pneumoniae, and IgM and IgA class antibodies against Escherichia coli and Proteus mirabilis compared with healthy controls. When compared with the patients with RA, the AS patients had higher concentrations of IgA and IgG class antibodies only against K pneumoniae. The RA patients had higher IgM class antibody concentrations against all three studied Enterobacterias, when compared with the healthy controls, suggesting an enhanced mucosal immune response in these patients. A three month treatment with sulphasalazine did not decrease enterobacterial antibody concentrations in the 10 patients with AS.

CONCLUSION

There is strong direct evidence for an abnormal mucosal humoral immune response particularly to K pneumoniae in patients with AS.