T lymphocytes of rheumatoid arthritis patients show augmented reactivity to a fraction of mycobacteria cross-reactive with cartilage

Poncet's Disease (Reactive Arthritis Associated with Tuberculosis)

An 82-year-old man with miliary tuberculosis was admitted to our hospital. Approximately six weeks after starting anti-tuberculosis treatment, he complained of pain in the fingers, wrists, and ankles. A histopathological examination of the synovial biopsy revealed nonspecific chronic inflammation with no granulomas. Culture of the biopsy specimen yielded no acid-fast bacilli. Poncet's disease was diagnosed based on the clinical presentation, with no findings suggestive of other diseases. His joint pain rapidly improved with steroid therapy. Tuberculosis can cause arthritis through immune-mediated mechanisms without direct invasion in an entity known as Poncet's disease.

Haemophilus parasuis (Glaesserella parasuis) as a Potential Driver of Molecular Mimicry and Inflammation in Rheumatoid Arthritis

Background:Haemophilus parasuis (Hps; now Glaesserella parasuis) is an infectious agent that causes severe arthritis in swines and shares sequence similarity with residues 261–273 of collagen type 2 (Coll_261−273), a possible autoantigen in rheumatoid arthritis (RA).

Objectives/methods: We tested the presence of Hps sequencing 16S ribosomal RNA in crevicular fluid, synovial fluids, and tissues in patients with arthritis (RA and other peripheral arthritides) and in healthy controls. Moreover, we examined the cross-recognition of Hps by Coll_261−273-specific T cells in HLA-DRB1^*04^pos RA patients, by T-cell receptor (TCR) beta chain spectratyping and T-cell phenotyping.

Results:Hps DNA was present in 57.4% of the tooth crevicular fluids of RA patients and in 31.6% of controls. Anti-Hps IgM and IgG titers were detectable and correlated with disease duration and the age of the patients. Peripheral blood mononuclear cells (PBMCs) were stimulated with Hps virulence-associated trimeric autotransporter peptide (VtaA10_755−766), homologous to human Coll_261−273 or co-cultured with live Hps. In both conditions, the expanded TCR repertoire overlapped with Coll_261−273 and led to the production of IL-17.

Discussion: We show that the DNA of an infectious agent (Hps), not previously described as pathogen in humans, is present in most patients with RA and that an Hps peptide is able to activate T cells specific for Coll_261−273, likely inducing or maintaining a molecular mimicry mechanism.

Conclusion: The cross-reactivity between VtaA10_755−766 of a non-human infectious agent and human Coll_261−273 suggests an involvement in the pathogenesis of RA. This mechanism appears emphasized in predisposed individuals, such as patients with shared epitope.

Patterns of T and B cell responses to Mycobacterium tuberculosis membrane-associated antigens and their relationship with disease activity in rheumatoid arthritis patients with latent tuberculosis infection

This study was aimed at exploring whether latent tuberculosis infection (LTBI) contributes to the pathogenesis of immune-mediated inflammatory diseases in a TB endemic setting. We screened 198 rheumatoid arthritis (RA) patients with tuberculin skin test (TST) and studied 61 (median DAS28-ESR = 6.3) who were positive. Whole blood T cell proliferative responses to Mycobacterium tuberculosis (Mtb) membrane (MtM) antigens, including the latency-induced protein alpha crystallin (Acr), were determined by flow cytometry using Ki67 expression as the marker for nuclear proliferation. Serum antibody levels were determined by ELISA. Follow-up investigations (at 3–6, 9–12 and 15–18 months after baseline) were performed in 41 patients who were classified empirically as ‘high’ (HR-T/HR-B) or ‘low’ (LR-T/LR-B) responders based on their dynamic T cell or antibody responses. Significant correlations were seen between baseline T cell responses to MtM and Acr, and between IgG, IgA and IgM antibody responses to MtM. However, no correlation was seen between T and B cell responses. At all time points during the follow-up, T cell responses to both antigens (except for MtM at one point) were significantly higher in HR-T (n = 25) than LR-T (n = 16) patients. Levels of IgA and IgM (but not IgG) antibodies to MtM were also significantly higher in HR-B (n = 13) than LR-B (n = 28) at all time points. Importantly, HR-T patients exhibited significantly higher baseline and follow-up DAS28 scores than LR-T. Ten (of 61) patients had a history of TB and developed RA 6 years (median) after contracting TB. Three new TB cases (1 from TST-positive and 2 from TST-negative groups) emerged during the follow-up. Our results suggest that persistently elevated T cell responses to Mtb antigens may contribute to disease activity in RA.

The gut microbiota modulator berberine ameliorates collagen-induced arthritis in rats by facilitating the generation of butyrate and adjusting the intestinal hypoxia and nitrate supply

The commensal microbiota is one of the environmental triggers of rheumatoid arthritis (RA). Recent studies have identified the characteristics of the gut microbiota in patients with RA. However, it is still unclear how the microbiota can be modulated to slow down disease progression. In the present study, berberine, a modulator of gut microbiota with substantial anti-RA effect, was chosen to explore the mechanisms by which the microbiota modulators ameliorate RA. The results showed that oral administration of berberine alleviated collagen-induced arthritis (CIA) in rats in a gut microbiota-dependent manner. Berberine down-regulated the diversity and richness of the gut bacteria, reduced the abundance of Prevotella, and elevated the abundance of butyrate-producing bacteria in CIA rats as determined by the 16S rRNA gene sequence, which might function through limiting the generation of nitrate and stabilizing the physiologic hypoxia in the intestine. Moreover, berberine treatment significantly increased the intestinal butyrate level and promoted the expression and activity of butyryl-CoA:acetate-CoA transferase (BUT). The coadministration of a BUT inhibitor largely diminished the adjustment of intestinal environment and the antiarthritic effect of berberine. In conclusion, modulators of the gut microbiota might serve as therapeutic agents for RA by inducing the butyrate generation through promoting the expression and activity of BUT.-Yue, M., Tao, Y., Fang, Y., Lian, X., Zhang, Q., Xia, Y., Wei, Z., Dai, Y. The gut microbiota modulator berberine ameliorates collagen-induced arthritis in rats by facilitating the generation of butyrate and adjusting the intestinal hypoxia and nitrate supply.

The Enigma of Heat Shock Proteins in Immune Tolerance

The fundamental problem of autoimmune diseases is the failure of the immune system to downregulate its own potentially dangerous cells, which leads to destruction of tissue expressing the relevant autoantigens. Current immunosuppressive therapies offer relief but fail to restore the basic condition of self-tolerance. They do not induce long-term physiological regulation resulting in medication-free disease remissions. Heat shock proteins (HSPs) have shown to possess the capacity of inducing lasting protective immune responses in models of experimental autoimmune diseases. Especially mycobacterial HSP60 and HSP70 were shown to induce disease inhibitory IL-10-producing regulatory T cells in many different models. This in itself may seem enigmatic, since based on earlier studies, HSPs were also coined sometimes as pro-inflammatory damage-associated molecular patterns. First clinical trials with HSPs in rheumatoid arthritis and type I diabetes have also indicated their potential to restore tolerance in autoimmune diseases. Data obtained from the models have suggested three aspects of HSP as being critical for this tolerance promoting potential: 1. evolutionary conservation, 2. most frequent cytosolic/nuclear MHC class II natural ligand source, and 3. upregulation under (inflammatory) stress. The combination of these three aspects, which are each relatively unique for HSP, may provide an explanation for the enigmatic immune tolerance promoting potential of HSP.

Proteins Differentially Expressed in the Pancreas of Hepatic Alcohol Dehydrogenase-Deficient Deer Mice Fed Ethanol For 3 Months

OBJECTIVES

The aim of this study was to identify differentially expressed proteins in the pancreatic tissue of hepatic alcohol dehydrogenase-deficient deer mice fed ethanol to understand metabolic basis and mechanism of alcoholic chronic pancreatitis.

METHODS

Mice were fed liquid diet containing 3.5 g% ethanol daily for 3 months, and differentially expressed pancreatic proteins were identified by protein separation using 2-dimensional gel electrophoresis and identification by mass spectrometry.

RESULTS

Nineteen differentially expressed proteins were identified by applying criteria established for protein identification in proteomics. An increased abundance was found for ribosome-binding protein 1, 60S ribosomal protein L31-like isoform 1, histone 4, calcium, and adenosine triphosphate (ATP) binding proteins and the proteins involved in antiapoptotic processes and endoplasmic reticulum function, stress, and/or homeostasis. Low abundance was found for endoA cytokeratin, 40S ribosomal protein SA, amylase 2b isoform precursor, serum albumin, and ATP synthase subunit β and the proteins involved in cell motility, structure, and conformation.

CONCLUSIONS

Chronic ethanol feeding in alcohol dehydrogenase-deficient deer mice differentially expresses pancreatic functional and structural proteins, which can be used to develop biomarker(s) of alcoholic chronic pancreatitis, particularly amylase 2b precursor, and 60 kDa heat shock protein and those involved in ATP synthesis and blood osmotic pressure.

Recombinant human HSP60 produced in ClearColi™ BL21(DE3) does not activate the NFκB pathway

HSP60, an intracellular molecular chaperone has been largely described as an alarmin or damage-associated molecular pattern when released outside the cell. HSP60 has been reported as a possible ligand of TLR2 or TLR4 inducing NFκB-dependant signaling pathway leading to cytokine secretion. However, recent publications suggested that HSP60 could not act as an activator of TLR4 by itself. The observed effect could be due to the presence of endotoxin in HSP60 preparation especially LPS. In order to clarify the controversy, we produced recombinant human HSP60 in two different strains of Escherichia coli, standard strain for protein overproduction, BL21(DE3), and the new ClearColi BL21(DE3) strain which lacks LPS-activity through TLR4. Undoubtedly, we have shown that recombinant HSP60 by itself was not able to induce NFκB-dependant signaling pathway in a model of THP1 monocyte cell line. Our data suggest that HSP60 needs either pathogen-associated molecules, specific post-translational modification and/or other host factors to activate immune cells via NFκB activation.

Multifactorial comparative proteomic study of cytochrome P450 2E1 function in chronic alcohol administration

With the use of iTRAQ technique, a multifactorial comparative proteomic study can be performed. In this study, to obtain an overview of ethanol, CYP2E1 and gender effects on liver injury and gain more insight into the underlying molecular mechanism, mouse liver proteomes were quantitatively analyzed using iTRAQ under eight conditions including mice of different genders, wild type versus CYP2E1 knockout, and normal versus alcohol diet. A series of statistical and bioinformatic analyses were explored to simplify and clarify multifactorial comparative proteomic data. First, with the Principle Component analysis, six proteins, CYP2E1, FAM25, CA3, BHMT, HIBADH and ECHS1, involved in oxidation reduction, energy and lipid metabolism and amino acid metabolism, were identified as the most differentially expressed gene products across all of the experimental conditions of our chronic alcoholism model. Second, hierarchical clustering analysis showed CYP2E1 knockout played a primary role in the overall differential protein expression compared with ethanol and gender factors. Furthermore, pair-wise multiple comparisons have revealed that the only significant expression difference lied in wild-type and CYP2E1 knockout mice both treated with ethanol. Third, K-mean clustering analysis indicated that the CYP2E1 knockout had the reverse effect on ethanol induced oxidative stress and lipid oxidation. More importantly, IPA analysis of proteomic data inferred that the gene expressions of two upstream regulators, NRF2 and PPARα, regulated by chronic alcohol feeding and CYP2E1 knockout, are involved in ethanol induced oxidative stress and lipid oxidation. The present study provides an effectively comprehensive data analysis strategy to compare multiple biological factors, contributing to biochemical effects of alcohol on the liver. The mass spectrometry proteomics data have been deposited to the ProteomeXchange with data set identifier of PXD000635.

Anti-Proteus activity of some South African medicinal plants: their potential for the prevention of rheumatoid arthritis

A wide variety of herbal remedies are used in traditional African medicine to treat rheumatoid arthritis (RA) and inflammation. Thirty-four extracts from 13 South African plant species with a history of ethnobotanical usage in the treatment of inflammation were investigated for their ability to control two microbial triggers for RA (Proteus mirabilis and Proteus vulgaris). Twenty-nine of the extracts (85.3 %) inhibited the growth of P. mirabilis and 23 of them tested (67.7 %) inhibited the growth of P. vulgaris. Methanol and water extracts of Carpobrotus edulis, Lippia javanica, Pelargonium viridflorum, Ptaeroxylon obliquum, Syzygium cordatum leaf and bark, Terminalia pruinoides, Terminalia sericea, Warburgia salutaris bark and an aqueous extract of W. salutaris leaf were effective Proteus inhibitors, with MIC values <2,000 μg/ml. The most potent extracts were examined by Reverse phase high performance liquid chromatography and UV-Vis spectroscopy for the presence of resveratrol. Only extracts from T. pruinoides and T. sericea contained resveratrol, indicating that it was not responsible for the anti-Proteus properties reported here. All extracts with Proteus inhibitory activity were also either non-toxic, or of low toxicity in the Artemia nauplii bioassay. The low toxicity of these extracts and their inhibitory bioactivity against Proteus spp. indicate their potential for blocking the onset of rheumatoid arthritis.

Clinical features of Poncet's disease. From the description of 198 cases found in the literature

Poncet's disease (PD) is an entity described as a reactive arthritis due to tuberculous infection elsewhere from the joints. PD existence has been questioned; however, more cases have been reported over the years. Due to its rare nature, little is known about the clinical picture of this disease and no prospective studies had been made to address this issue. We performed a systematic review of the written literature on PD in different databases using the key words "Poncet's disease," "tuberculous rheumatism," and "tuberculous reactive arthritis." Out of 78 articles, 198 patients were included in the analysis, plus our patient. Several characteristic patterns were found. Also, a review of the pathogenesis and some hypotheses are made. PD is a well-defined entity, which should be taken as a reactive arthritis for future studies given the increase in TB incidence and prevalence around the world, especially in high-burden countries.

[Acute arthritis secondary to intravesical bacillus Calmette-Guérin for bladder cancer]

INTRODUCTION

We sought to identify the prevalence, presentation, treatment, and prognosis of acute arthritis secondary to intravesical bacilli Calmette-Guérin (BCG) therapy for bladder cancer.

METHODS

We performed a structured, systematic review of the English language literature pertaining to BCG and reactive arthritis among bladder cancer patients. We extracted data pertaining to prevalence, presentation, management, and prognosis.

RESULTS

We extracted 23 individual case reports and 4 review articles. Thirty-nine patients -31 (80%) male and 8 (20%) female- were described in these publications; we also identified 1 patient from our institution. Although prevalence estimates of reactive arthritis range from 0.5 to 1.0% of all bladder cancer patients receiving BCG, the true prevalence remains unclear. Polyarthritis (68%) and fever (58%) were the most common presenting symptoms. Among patients presenting with joint pain, the knees (41%), ankles (26%), and wrists (19%) were most often affected. The most common time of presentation was immediately following the 4th instillation of a 6-week induction course (25%). Initial therapy in 100% of patients was discontinuation of BCG. Other therapies included nonsteroidal anti-inflammatory drugs (NSAIDs) (25%); steroids (8%); anti-tubercular medications (8%); and combined NSAIDs, steroids, and anti-tubercular medications (20%).

CONCLUSIONS

Reactive arthritis is an infrequent but potentially severe complication of intravesical BCG for bladder cancer that typically presents with polyarthritis and fever during induction. The most common treatments include immediate discontinuation of BCG and systemic anti-inflammatory therapy. Further studies are needed to determine prevalence, pathophysiology, and long-term prognosis.

Leprosy and rheumatoid arthritis: consequence or association?

Leprosy or Hansen's disease is a chronic granulomatous infectious disease caused by Mycobacterium leprae with a high prevalence in some developing countries however, it is rarely seen in non-endemic regions. Arthritis has been described in all types of Hansen's disease. Chronic arthritis is known to exist even in paucibacillary forms, resolved or treated disease and in patients without reaction, suggesting a perpetuated inflammatory process. In these cases leprosy can mimic some autoimmune diseases such as rheumatoid arthritis. When a patient with a history of leprosy presents with a symmetric, distal, polyarthritis the diagnosis may not be linear. Possibly it is a rheumatoid-like leprous arthritis with M leprae acting as the trigger element for the chronic process or it is an overlap condition, with a concomitant rheumatoid arthritis? A case report of a patient with a chronic inflammatory arthritis with 10 years of evolution is presented. The differential diagnosis between leprous and rheumatoid arthritis is discussed.

Mycobacterium tuberculosis, autoimmunity, and vitamin D

Mycobacterium tuberculosis (TB) is a major cause of morbidity and mortality worldwide. Current anti-TB chemotherapies, although effective, are associated with side effects and are limited in treating drug-resistant strands. Autoimmune diseases are a leading cause of morbidity and mortality, with a growing mass of evidence implicating infections (e.g., TB) as their triggers. The burden of TB might further increase by reactivation threats hovering over millions harboring latent infection, thus, calling for novel approaches for this dire ailment. In recent years, the non-calcemic physiological actions of vitamin D have drawn a great deal of attention. In this review, we will focus on the role of vitamin D in the innate immune defense against TB on the one hand and conversely on the immunomodulatory effects of vitamin D on autoimmunity. Taken together, the suggested dual role of vitamin D in treating TB infection and possibly preventing associated autoimmunity will constitute the basis of the current review.

[Acute reactive arthritis after intravesical instillation of bacillus Calmette-Guérin. Two case reports and literature review]

INTRODUCTION

Intravesical bacillus Calmette-Guérin (BCG) therapy-associated articular complications are uncommon, occurring in only 0.5 to 1% of the patients.

OBSERVATIONS

We report two patients who were given intravesical BCG therapy for superficial bladder cancer. Both patients developed polyarthritis and fever related to intravesical BCG instillation. The outcome of articular manifestations was favorable after administration of nonsteroidal anti-inflammatory therapy.

CONCLUSION

Intravesical BCG therapy-associated articular complications should not be overlooked, as they may result in high morbidity. Nevertheless, the diagnosis of intravesical BCG therapy-related reactive arthritis should be discussed after excluding infectious arthritis due to Mycobacterium bovis. Therefore, joint fluid microbiological tests (cultures, PCR) are required in the patients receiving intravesical BCG who develop arthritis.

Identification of proteins to predict the molecular basis for the observed gender susceptibility in a rat model of alcoholic steatohepatitis by 2-D gel proteomics

Females are reported to be highly susceptible to alcoholic steatohepatitis (ASH) compared to the males. Although a variety of mechanisms have been proposed to explain this higher sensitivity of females, the precise mechanism is not well understood. The objective of this study was to identify changes in global protein expression in liver tissues of male and female rats with pathologically evident ASH by 2-DE (dimensional electrophoresis). ASH was induced in the SD (Sprague-Dawley) rats by feeding ethanol (EtOH) containing Lieber-DeCarli diet for 6 wk followed by a single injection of lipopolysaccharide (LPS, 10 mg/kg, i.p.). Higher liver injury in females in the ASH group as compared to the males was confirmed by HE stained liver sections. As identified by 2-DE, 22 protein-spots were differentially expressed in the females in the ASH group as compared to the males. Following identification of these proteins by MALDI-MS, they were mainly categorized into metabolism and oxidative stress-related proteins. The expression pattern of a few of these oxidative stress-related proteins like Ferritin Heavy chain (Ferritin-H chain), ER stress protein 60 (ER 60) and Heat-shock protein-60 (HSP 60) were verified by Western blotting. To conclude, the current study has identified a set of proteins that highlights potential novel mechanisms associated with higher liver injury noted in the female rat ASH model.

A measles-derived peptide treats and vaccinates against adjuvant arthritis

Measles vaccine and porcine myelin basic protein were both found to ameliorate or abolish the symptoms of adjuvant arthritis (AA) in Lewis rats whether inoculated at the time of adjuvant administration or after the onset of arthritis. These results are consistent with clinical observations that measles infection can sometimes cause remission of juvenile rheumatoid arthritis. The fact that measles virus proteins and myelin basic protein have significant regions of homology allowed peptides based on these regions to be synthesized. A twenty-amino acid sequence exhibits significant anti-arthritic activity when inoculated into rats with pre-existing AA and it also prevented onset of AA when a single dose was preinoculated three weeks prior to AA induction. These data suggest the possibility of developing novel therapeutic vaccines against some forms of arthritis.

The dynamics of articular leukocyte trafficking and the immune response to self heat-shock protein 65 influence arthritis susceptibility

INTRODUCTION

Adjuvant arthritis (AA) shares several features with human rheumatoid arthritis, and it can be induced in the Lewis (LEW) rat but not the Wistar Kyoto (WKY) rat (both RT.1(l)) by immunization with heat-killed Mycobacterium tuberculosis (Mtb). We set out to unravel the mechanisms underlying the differential susceptibility to AA of these MHC-compatible rat strains.

MATERIALS AND METHODS

We compared the levels of T-cell proliferative and cytokine response to the immunoregulatory self (rat) hsp65 (Rhsp65) after an arthritogenic (Mtb) challenge and the kinetics of migration of adoptively transferred, (111)Indium-labeled, Mtb-primed leukocytes into the hind paw joints of recipient rats.

RESULTS AND DISCUSSION

The WKY rats raised a significantly higher level of T-cell proliferative response coupled with a temporally opposite cytokine profile against the disease-regulating Rhsp65 compared to that of LEW rats. Moreover, the arthritogenic leukocytes accumulated into the joints of WKY rats at significantly lower numbers than that in LEW rats.

CONCLUSIONS

These results offer novel insights into the immune events influencing the pathogenesis of autoimmune arthritis.

Rheumatoid arthritis is linked to Proteus--the evidence

Rheumatoid arthritis (RA) is a chronic inflammatory arthritic and potentially disabling condition, mainly affecting women of middle age and having characteristic clinical features. Various microbial agents were implicated in the causation of RA. Extensive literature based on the results of various genetic, microbiological, molecular, and immunological studies carried out by independent research groups supports the role of Proteus mirabilis bacteria in the etiopathogenesis of RA. New diagnostic markers and criteria and the use of a novel therapeutic protocol in the form of antibiotic and dietary measures are suggested to be used together with current treatments in the management of RA. Prospective longitudinal studies with the use of antimicrobial measures in patients with RA are required to establish the therapeutic benefit of this microbe-disease association.

Strain differences and the role for HSP47 and HSP70 in adjuvant arthritis in rats

Because of high sequence homology between microbial and endogenous heat shock proteins (HSP), immunological cross-reactivity to microbial HSP has been suggested as a possible cause of the development of autoimmune diseases, such as rheumatoid arthritis. The present study aimed to determine a potential role of HSP47, a molecular chaperone involved in the synthesis and assembly of collagen molecules, and microbial HSP71 (mHSP71) in adjuvant arthritis (AA) in two rat strains: Dark Agouti (DA), susceptible to AA induction and Albino Oxford (AO), which is resistant to AA induction. Immunization with complete Freund's adjuvant (CFA) induced an increased expression of HSP47 in joints of DA rats, which exhibited severe clinical signs of AA at the time of disease peak, while this protein was not detectable in joints of AO rats. In contrast, no strain differences in HSP72 (rat analogue of mHSP71) expressions in joints were observed. The increased levels of anti-HSP47 antibodies were detected in sera of DA rats during the AA peak, while the immunization with CFA increased levels of anti-mHSP71 antibodies in sera of AO rats. HSP47 and mHSP71 reduced proliferation of draining inguinal lymph node cells (LNC) in resistant AO rat strain, leading to a hypothesis that both HSP participated in AA control. Finally, mHSP71 potentiated the apoptotic response of LNC in susceptible DA rat strain. In conclusion, our findings indicate involvement of HSP47 in the development of AA in the rat, and point out to the regulatory role for both HSP47 and mHSP71.

BCG immunotherapy – from pathophysiology to clinical practice

Treatment with Bacillus Calmette-Guérin vaccine is mainly in use for superficial bladder cancer, for which it is given intravesically. Overall, this therapy is safe with only minor side effects. Arthritis secondary to such therapy has been rarely reported and usually responds well to NSAID treatment. The mechanisms leading to such a complication, as well as the clinical data, are discussed.

Osteoarticular side effects of BCG therapy

Although osteoarticular side effects of the Bacillus Calmette-Guérin (BCG) are rare compared to the number of administrations, BCG vaccination and cancer therapy are so widely used that the absolute number of cases is not negligible. Osteoarticular infection is an exceedingly rare complication of vaccination with the BCG. Intravesical BCG instillations used to treat superficial bladder cancer may cause arthralgia, reactive arthritis or osteoarticular infections. Intradermal BCG therapy used to treat a number of malignancies can cause osteoarticular infections or bilateral symmetric polyarthritis predominating in the wrists and fingers. In practice, when intravesical BCG instillation is followed by arthritis, hyperthermia is unhelpful for distinguishing septic arthritis from reactive arthritis. Arguments pointing to reactive arthritis include oligo- or polyarticular involvement and onset a few weeks (as opposed to a few months) after the last instillation. Nevertheless, joint fluid examination is in order to rule out septic arthritis. BCG-induced reactive arthritis usually responds well to nonsteroidal anti-inflammatory drugs. Osteoarticular infections related to BCG therapy should be treated by rifampin, isoniazid and ethambutol for 2 months, followed by rifampin and isoniazid for 10 months.

Skewed T-cell receptor BV14 and BV16 expression and shared CDR3 sequence and common sequence motifs in synovial T cells of rheumatoid arthritis

T-lymphocytes play an important role in rheumatoid arthritis (RA). In this study, we evaluated the hypothesis that common T-cell receptor (TCR) structural features may exist among infiltrating T cells of different RA patients, if the TCR repertoire is shaped by interaction with common self or microbial antigens in the context of susceptible HLA genes in RA. Synovial lesion tissue (ST), synovial fluid (SF) and blood specimens from RA patients and controls were analyzed for TCR V gene repertoire by real-time PCR. There was highly skewed BV14 and BV16 usage in synovial T cells of RA as opposed to those of controls, which was accompanied with a trend for correlation between skewed BV16 and DRB1(*)0405. Immunoscope analysis of the V-D-J region of ST-derived T cells demonstrated oligoclonal and polyclonal expansion of BV14(+) and BV16(+) T cells. Detailed characterization using specific BV and BJ primers further revealed common clonotypes combining the same BV14/BV16, BJ and CDR3 length. DNA cloning and sequence analysis of the clonotypes confirmed identical CDR3 sequences and common CDR3 sequence motifs among different RA patients. The findings are important in the understanding of BV gene skewing and CDR3 structural characteristics among synovial infiltrating T cells of RA.

Identification of the heat shock protein 60 epitope involved in receptor binding on macrophages

In the present study, we identified the human heat shock protein 60 (HSP60) epitope responsible for binding to macrophages. Studies using overlapping 15- and 20-mer peptides of the human HSP60 sequence to compete with binding of HSP60 to macrophages indicated that surface binding was accounted for by the region aa481-500. Deletion mutants of HSP60, lacking the N-terminal 137, 243 or 359 amino acids, strongly inhibited HSP60 binding to macrophages. Monoclonal antibodies addressing regions aa1-200, aa335-366 or aa383-447 did not block HSP60 binding. We conclude that a single C-terminal region, aa481-500, accounts for the binding of HSP60 to macrophages.

Immune regulation in adjuvant disease and other arthritis models: relevance to pathogenesis of chronic arthritis

Experimental models of arthritis and their human counterparts fall into three distinct classes: (a) responses of T cells to disseminated microbial antigens (Ags) as such; (b) responses of T cells to cartilage autoAgs; and (c) responses of T cells to major histocompatibility complex (HLA-B27, DRB1) or other membrane components (LFA-1) expressed on bone marrow-derived cells. The primary immune response is driven, in naturally occurring disease, by microbial infection, e.g. with streptococci, enteric gram-negative rods or spirochetes, or is experimentally induced with mycobacterial and other adjuvants. The response to cartilage components, such as collagen type-II and various proteoglycans, may be driven by cross-reactive microbial Ags, heat shock proteins (HSPs) in particular, or the adjuvant effect of intense primary joint inflammation, as in rheumatoid arthritis and the spondyloarthropathies. Adjuvant disease appears to be purely T-cell-mediated, whereas both T cells and antibody play a role in collagen and many other forms of arthritis. Experimental evidence suggests a pathogenetic role for T-cell receptor gammadelta T cells in some lesions. Arthritis may be regulated by microbial and tissue HSPs, when these are administered by a nonimmunizing route or as altered peptide ligands, by anti-idiotypic responses that block the action of effector T cells, and by competing Ags. Immune regulation involving natural killer (NK), NK T and certain subsets of gammadelta and alphabeta T cells, which may affect the occurrence, localization and character of this group of diseases, presents a challenge for further investigation.

Connectivity patterns in tuberculosis and leprosy patients are indistinguishable from that of healthy donors

Connectivity, the self-defined interactions between antigen-recognising molecules in a network system can in part be assessed by measuring the reactivity of a given serum against an ordered set of immunoglobulin (Ig)G F(ab')2 fractions, separated by means of isoelectric focusing so that, the serum reactivity against the whole set of fractions defines a characteristic pattern of connectivity. Deviations from the normal condition (healthy donors) have so far been documented for two autoimmune diseases: systemic lupus erythematosus (SLE) and pemphigus vulgaris, as well as for human immunodeficiency virus (HIV)-1 infection. We tested here if bacterial infections lead to alterations in connectivity. In addition, we wanted to test if two antigenically related bacteria would produce similar or otherwise distinctive connectivity patterns. Connectivity analysis was applied on the sera from tuberculosis and leprosy patients and the sera from healthy donors were used as control. No statistically significant differences between the three groups studied were found. These results have implications for theories that set the origin of autoimmune diseases in microbial infections. To the best of our knowledge, this is the first attempt to analyze the connectivity status in bacterial infections.

Bcg and autoimmunity: another two-edged sword

BCG immunotherapy for bladder carcinoma has been a long-standing treatment modality that has proved itself efficient and safe. Most of the side-effects of this treatment are minor and of short duration. There have been, nevertheless, several reports regarding more severe and long-term complications of BCG therapy-namely inflammatory arthritis, and occasionally systemic autoimmune manifestations. Here, we present four cases of patients who received intravesical instillation with BCG for bladder carcinoma and developed long-standing inflammatory arthritis. One of these patients developed Reiter's syndrome. We also refer to the possible immune mechanisms by which BCG can trigger arthritis, as well as to the link between mycobacterial infection, BCG immunotherapy and autoimmunity.

Detection of Mycobacterium tuberculosis group organisms in human and mouse joint tissue by reverse transcriptase PCR: prevalence in diseased synovial tissue suggests lack of specific association with rheumatoid arthritis

Infection with mycobacterial species, including Mycobacterium tuberculosis, has long been implicated in the etiopathology of rheumatoid arthritis (RA) on the basis of clinical and pathological similarities between tuberculosis and RA. Despite evidence of immune responses to mycobacterial antigens in RA patient synovial fluid, cross-reactivity between these and host joint antigens, and the presence of M. tuberculosis protein antigen in RA synovial fluid, a definite causal association with RA has not been shown. Previous studies from our laboratory using reverse transcriptase PCR (RT-PCR) of bacterial rRNAs have shown RA synovium to be colonized by a diverse range of bacteria, most of commensal origin. However, M. tuberculosis group organism (MTG) RNA sequences were found in one RA patient tissue. Since this was considered of sufficient interest to warrant further investigation, we devised a M. tuberculosis-specific nested RT-PCR test which could be used for detection of MTG in a mixed pool of bacterial crDNAs. This test was used to investigate the distribution of MTG in RA synovial tissue and also non-RA arthritis and healthy control tissues and was also used to examine the tissue distribution of MTG in an acute and chronic model of M. tuberculosis infection in the BALB/c mouse. MTG sequences were found in a high proportion of RA patient synovial tissues but also in non-RA arthritis control tissues at lower frequency. This likely reflects trafficking of persistent M. bovis BCG to inflamed joint tissue, irrespective of cause. MTG were not found in healthy synovial tissue or the tissue of patients with undifferentiated arthritis. In both the acute and chronic models of infection in BALB/c mice, M. tuberculosis was also found to have trafficked to joint tissues, however, no signs of inflammation, arthritis, or pathology associated with M. tuberculosis infection was seen. These combined results would argue against a specific causal role of MTG in RA-like arthritis; however, their role as adjuvant in immune dysfunction in an innately susceptible host cannot be excluded.

Autoantibodies against chaperonin CCT in human sera with rheumatic autoimmune diseases: comparison with antibodies against other Hsp60 family proteins

Chaperonin CCT containing t-complex polypeptide 1 is a cytosolic molecular chaperone that assists in the folding of actin, tubulin, and other proteins and is a member of the 60-kDa heat shock protein (Hsp60) family. We examined antibody titers against human CCT and other Hsp60 family members in the sera of patients with rheumatic autoimmune diseases, including rheumatoid arthritis, systemic lupus erythematodes, Sjögren syndrome, and mixed connective tissue disease. Autoantibody titers against not only human mitochondrial Hsp60 but also CCT were significantly higher in the sera of patients with rheumatic autoimmune diseases than in healthy control sera. Although immunoglobulin G (IgG) titers against Escherichia coli GroEL were high in all the groups of sera tested, no significant differences in anti-GroEL responses were detected between patients and healthy controls. IgG titers against mycobacterial Hsp65 showed a similar pattern to titers of autoantibodies recognizing GroEL. Immunoabsorption experiments demonstrated that most of the autoantibodies recognizing CCT were cross-reactive with mitochondrial Hsp60, E coli GroEL, and mycobacterial Hsp65. Although most of the anti-Hsp60 IgG recognized CCT, anti-GroEL (or antimycobacterial Hsp65) IgG contained antibodies specific for GroEL (or mycobacterial Hsp65) in addition to antibodies cross-reactive with CCT and Hsp60. Results from immunoblot analyses, together with weak (15% to 20%) amino acid sequence identities between CCT and the other Hsp60 family members, suggested that CCT-reactive autoantibodies recognize conformational epitopes that are conserved among CCT and other Hsp60 family members.

Characteristics of polyarthritis in rabbits by hyperimmunization with attenuated Enterococcus faecalis

To produce polyarthritis and rheumatoid factor like substance (RFLS), rabbits were hyperimmunized intravenously with 0.02% thimelosal (TMS)-treated Enterococcus faecalis (E. faecalis) as a persistent bacterial flora. Swelling of knee joints occurred at a rate of 41% (27/66), and of shoulder joints at a rate of 25% (17/66) while that of elbow joints occurred at a rate of 4.5% (3/66). On culturing of knee joint fluids, no colonies appeared while 2/4 fluid specimens from the shoulder joints gave positive colonies for 78 days after the first immunization; thereafter, no colonies appeared. On histological examination, in early stages, acute inflammatory reactions with degenerative changes of synovial tissue was observed. In later stages, chronic inflammatory changes, proliferation of synovial cells with pannus formation, destruction of articular cartilage and subchondral bone were observed. RFLS titer showed bi-phasic peaks at 11 days and 41 days after the first immunization. A high incidence of polyarthritis, particularly knee joints, occurred. Thus, hyperimmunization with attenuated E. faecalis as a normal intestinal flora may provide an animal model of chronic polyarthritis.

In vitro expansion of T-cell-receptor Valpha2.3(+) CD4(+) T lymphocytes in HLA-DR17(3), DQ2(+) individuals upon stimulation with Mycobacterium tuberculosis

The T-cell receptor (TCR) Valpha/beta gene product expression upon in vitro stimulation with mycobacteria was investigated to assess whether T-cell proliferation was associated with any specific TCR V gene usage. T-cell-enriched populations from peripheral blood of Mycobacterium bovis BCG-vaccinated healthy blood donors were stimulated in vitro with live or killed M. tuberculosis or with a soluble extract thereof. TCR Valpha/beta repertoire analysis of reactive CD4(+) and CD8(+) T cells revealed a selective HLA-DR17(3), DQ2-restricted expansion of Valpha2.3(+) CD4(+) T cells upon stimulation with live M. tuberculosis or its soluble extract. Third-complementarity-determining-region (CDR3) length analysis of the expanded Valpha2.3(+) T cells indicated an oligoclonal pattern with short CDR3 lengths in six of seven HLA-DR17(3), DQ2(+) individuals tested. In addition, Valpha/Vbeta repertoire analysis of T lymphocytes from a DR17(3), DQ2(+) donor before and after BCG vaccination revealed that positivity of skin test reactivity was associated with expansion of Valpha2.3(+) CD4(+) T lymphocytes with preferential use of a short CDR3 peak length after in vitro stimulation. Separation of M. tuberculosis soluble extract by fast protein liquid chromatography (FPLC) purification indicated that fractions corresponding to molecular masses of 60 to 70 and 15 to 25 kDa were particularly effective in eliciting Valpha2.3(+) CD4(+) T-cell expansion.

Gammadelta receptor bearing T cells in scleroderma: enhanced interaction with vascular endothelial cells in vitro

In view of the documented perivascular mononuclear cell infiltration in the involved organs in scleroderma (SSc) and the reported accumulation of gammadelta-T cells in SSc skin and lung, we evaluated gammadelta-T cell interaction with endothelial cells (EC) in vitro. gammadelta- and alphabeta-T cells were isolated from BPMN of SSc patients with early diffuse disease and of matched control subjects by an immunomagnetic method after stimulation with mycobacterium lysate and interleukin-2 for 2 weeks. Lymphocyte adhesion, proliferation, and cytotoxicity to EC were investigated. SSc gammadelta-T cells adhered to cultured EC and proliferated at higher rates than control cells. Furthermore, significant EC cytotoxicity by SSc gammadelta was seen. The cytotoxicity was blocked by addition of anti-gammadelta-TCR antibody and by anti-granzyme A antibody but not by anti-MHC class I and II antibodies. Expression of granzyme A mRNA was seen in five/five SSc gammadelta-T cells and in one/five control cells. alphabeta-T cells from both SSc and control subjects were significantly less interactive with EC than gammadelta-T cells. The data demonstrate EC recognition by SSc gammadelta-T cells and propose gammadelta-T cells as a possible effector cell type in the immune pathogenesis of SSc.

Anti-heat shock protein 70 kDa and 90 kDa antibodies in serum of patients with rheumatoid arthritis

OBJECTIVES

Stress proteins (HSPs) are highly conserved immunodominant antigens found in various species. The purpose of this study was to assess the prevalence and prognostic significance of antibodies to HSC 70 kDa and HSP 90 kDa in three groups of patients with longstanding rheumatoid arthritis (RA) defined based on the severity of articular erosions.

METHODS

73 patients with longstanding (> 6 years) RA whose HLA-DR genotype was known were divided in three groups according to Larsen's score and compared with 47 recent onset (<1 year) RA patients and with control groups composed of patients with other inflammatory diseases (n=137) or of normal controls (n=48). IgGs and IgMs to HSC 70 kDa and HSP 90 kDa were determined using an ELISA with purified bovine HSC 70kDa or HSP 90 kDa.

RESULTS

Concentrations of IgGs and IgMs to HSC 70 were significantly increased in 41.1% and 42.5% of longstanding RA patients, respectively. Corresponding figures for IgGs and IgMs to HSP 90 were 39.7% and 56%. IgMs to HSC 70 and HSP 90 were less frequent in recent onset RA (19% and 13% respectively). Among the groups with other inflammatory diseases, only the MCTD group exhibited high frequencies of IgGs to HSC 70 (80%) and HSP 90 (85%). DRB1*0401 positive RA patients (n=23) were not more likely to have increased concentrations of antibodies to HSC 70 kDa or HSP 90 kDa than other RA patients (DR4 positive but DRB1*0401 negative, or DR1 positive, n=31; or negative for both DR4 and DR1, n=14). IgGs to HSP 90 kDa were significantly more frequent (p<0.05) in longstanding RA patients whose Larsen's score was 4 or more (57%) than in those whose Larsen's score was 2 or 3 (39.4%) or less than 2 (16%). No associations were found between Larsen's score and IgGs or IgMs to HSC 70 kDa or IgMs to HSP 90 kDa. A significant correlation was demonstrated between IgGs to HSP 90 kDa and two other serological markers for RA, rheumatoid factor, and anti-Sa antibody; there were no correlations with antikeratin antibody, antiperinuclear factor, or anti-RA 33.

CONCLUSION

IgGs to HSP 90 kDa are most common in longstanding RA patients with articular erosions, suggesting that they may be related to the articular prognosis in RA

Human 60-kDa Heat-Shock Protein: A Danger Signal to the Innate Immune System

Mammalian 60-kDa heat-shock protein (hsp60) is a key target of T cell and Ab responses in chronic inflammation or atherosclerosis. We show in this study that human hsp60 is also an Ag recognized by cells of the innate immune system, such as macrophages. Both mouse and human macrophages respond to contact with exogenous human hsp60 with rapid release of TNF-α; mouse macrophages in addition produce nitric oxide. The proinflammatory macrophage response is hsp60 dose dependent and similar in kinetics and extent to LPS stimulation. Human hsp60 was found to synergize with IFN-γ in its proinflammatory activity. Finally, human hsp60 induces gene expression of the Th1-promoting cytokines IL-12 and IL-15. These findings identify autologous hsp60 as a danger signal for the innate immune system, with important implications for a role of local hsp60 expression/release in chronic Th1-dependent tissue inflammation.

Successful Induction of Adjuvant Arthritis in Mice by Treatment with a Monoclonal Antibody Against IL-4

Adjuvant arthritis (AA) is an experimental model of autoimmune disease in rats induced by immunization with Mycobacterium tuberculosis (MT). Induction of AA in other species, including mice, has been shown to be difficult. In the present study, we found that AA could be induced in mice if the animals were treated with a mAb (11B11 mAb) against IL-4. Histologically, the joints exhibited synovial edema with infiltration of many neutrophils in the early phase of inflammation. In its late phase, there were proliferation of synovium, cell infiltrate in which mononuclear cells predominated, and destruction of cartilage and subchondral bone. The joint inflammation was passively transferred to normal syngeneic recipient mice with lymphoid cells but not with sera from mice immunized with MT followed by treatment with the anti-IL-4 Ab. Delayed-type hypersensitivity (DTH) and proliferative responses of lymphoid cells to purified protein derivative were markedly augmented in 11B11 mAb-treated mice. Furthermore, the induction of arthritis was associated with a marked decrease in IL-4 secretion but a significant increase in IFN-γ and IL-2 production. Thus, the neutralization of IL-4 by an anti-IL-4 Ab appears to be required for the induction of AA in mice.

HSP-derived peptides inducing uveitis and IgG and IgA antibodies

Heat shock protein (HSP) 65 kD-derived peptides, which specifically stimulate T cells from patients with Behçet's disease (BD), are capable of inducing uveitis in rats. Mycobacterial HSP 65 kD and BD-specific peptides were injected into Lewis rats and the development of uveitis was monitored clinically and histologically, and IgG and IgA antibodies were measured using an enzyme-linked immunosorbent assay (ELISA). Rats immunized with HSP peptides that developed uveitis showed significantly higher serum IgG antibody levels to peptide 311-326 (P < 0.05) and the corresponding homologous human peptide 336-351 (P < 0.01) than rats without uveitis. Significant increases in serum IgA antibodies in rats with uveitis were also observed in those immunized with peptides 111-125, 311-326 and 336-351 (P < 0.05). Rats injected with HSP 65 kD showed a rise in IgG antibody levels to peptides 111-125, 154-172 and 311-326 and to a lesser extent, a rise in IgA antibody level to peptide 311-326. HSP showed almost complete inhibition of binding of IgG antibodies to HSP 65 kD, but peptides 111-125, 154-172, 311-326 and 336-351 showed inhibition to a lesser extent in a competitive assay. These results suggest that increases in IgG and IgA antibody levels to specific peptides within HSP, develop in rats with uveitis. The T and B cell epitopes responsible for the development of ocular disease in rats immunized with HSP-derived peptides, appear to be similar or identical to those found in patients with the ocular type of BD.

Poor expression of T cell-derived cytokines and activation and proliferation markers in early rheumatoid synovial tissue

We compared the state of activation and proliferation of T cells in synovial tissue (ST) from rheumatoid arthritis (RA) patients in early and late stages of the disease to find out whether T-cell-driven immune responses vary during the course of the disease. ST was obtained from 12 patients with early RA (< 1 year) and 12 patients with longstanding RA (> 5 years). T cells and interferon-gamma (IFN-gamma)-positive cells were detected in ST using immunohistologic methods. To determine the percentage of T cells expressing the interleukin-2 receptor, IFN-gamma, or the proliferation associated antigen Ki-67, immunofluorescence double-staining techniques were used. The scores for the number of T cells and for the expression of IFN-gamma as well as the percentages of T cells expressing CD25, IFN-gamma, or Ki-67 in rheumatoid synovium were not dependent on disease duration. These results do not support the assumption that the responsiveness of T cells in ST of RA patients differs between early and late stages of the disease. The data indicate that at present no arguments exist that the effect of T-cell-directed interventions on synovial inflammation might vary in different stages of the disease.

TCRB clonotypes are present in CD4+ T cell populations prepared directly from rheumatoid synovium

The identification of clonal T cells at sites of inflammation is hampered by the large number of polyclonal T cells that nonspecifically accumulate. In this report, we combine the use of T cell sorting with spectratyping of the third complementarity determining region (CDR3) and direct sequence analysis to rapidly screen for and identify clonal expansions of T cells from synovial tissue specimens from patients with rheumatoid arthritis (RA). Initially, we used a polymerase chain reaction specific for the variable region gene of the T cell receptor beta chain (TCRBV) to compare the TCRBV repertoire expressed by CD4+ T cells from the peripheral blood and synovium of five patients with long-standing RA. Each patient had several TCRBV genes that were amplified to a greater degree from synovium. Extensive sequence analysis (n > 170) showed that each patient contained junctional sequences that occurred more than once, implying the presence of T cell clones within the starting CD4+ T cell population. To assess a more straightforward approach to identifying clones, six additional patients were recruited and CD4+, TCRBV2+ synovial T cells were positively selected and analyzed by CDR3 spectratyping. Bands deviating from a normal distribution were excised from the gel and sequenced directly. Clones were detected in half of the patients. These data are consistent with the possibility of an antigen-driven T cell response in RA that remains present in the setting of advanced disease.

Diversification of T cell responses to carboxy-terminal determinants within the 65-kD heat-shock protein is involved in regulation of autoimmune arthritis

The T cell response to the 65-kD mycobacterial heat-shock protein (Bhsp65) has been implicated in the pathogenesis of autoimmune arthritis. Adjuvant arthritis (AA) induced in the Lewis rat (RT-1(l)) by injection of Mycobacterium tuberculosis serves as an experimental model for human rheumatoid arthritis (RA). However, the immunological basis of regulation of acute AA, or of susceptibility/resistance to AA is not known. We have defined the specificity of the proliferative T cell responses to Bhsp65 during the course of AA in the Lewis rat. During the early phase of the disease (6-9 d after onset of AA), Lewis rats raised T cell responses to many determinants within Bhsp65, spread throughout the molecule. Importantly, in the late phase of the disease (8-10 wk after onset of AA), there was evidence for diversification of the T cell responses toward Bhsp65 carboxy-terminal determinants (BCTD) (namely, 417-431, 441-455, 465-479, 513-527, and 521-535). Moreover, arthritic rats in the late phase of AA also raised vigorous T cell responses to those carboxy-terminal determinants within self(rat) hsp65 (Rhsp65) that correspond in position to the above BCTD. These results suggest that the observed diversification is possibly triggered in vivo by induction of self(Rhsp65)-reactive T cells. Interestingly, another strain of rat, the Wistar Kyoto (WKY/NHsd) rat (RT-1(l)), with the same major histocompatibility complex class II molecules as the Lewis rat, was found to be resistant to AA. In WKY rats, vigorous responses to the BCTD, to which the Lewis rat responded only in the late phase of AA, were observed very early, 10 d after injection of M. tuberculosis, Strikingly, pretreatment with the peptides comprising the set of BCTD, but not its amino-terminal determinants, provided significant protection to naive Lewis rats from subsequent induction of AA. Thus, T cell responses to the BCTD are involved in regulating inflammatory arthritis in the Lewis rat and in conferring resistance to AA in the WKY rat. These results have important implications in understanding the pathogenesis of RA and in devising new immunotherapeutic strategies for this disease.

Possible mechanisms of chronic leprosy-related arthritis

Microbial agents induce arthritis through mechanisms such as direct infiltration of tissue and by inducing autoimmune phenomena. The mechanisms involved in this last type of arthritis have been investigated. In experimental models of adjuvant and reactive arthritis, the involvement of T cells in some cases mycobacteria in the development of arthritis have been confirmed. Cross-reactivity between the 65 kD mycobacterial protein and cartilage proteoglycans has been postulated as a possible mechanism. In this study, chronic peripheral arthritis was observed in patients with Hansen's disease, in patients with resolved Hansen's and in those with paucibacillary forms. This arthritis was not related to reactional states (erythema nodosum leprosum and reversal reaction), in contrast to several reports in the literature. The mechanisms by which microbes could induce chronic arthritis are discussed herein.

Analysis of the synovial cell infiltrate in early rheumatoid synovial tissue in relation to local disease activity

OBJECTIVE

To define variations in the cellular infiltrate and in the expression of monokines in synovial tissue (ST) from rheumatoid arthritis (RA) patients with different durations of disease and different levels of disease activity.

METHODS

The immunohistologic features of synovial biopsy specimens from 31 patients with early RA (< 1 year) and 35 patients with longstanding RA (> 5 years) were compared. The possible associations between these features and local disease activity, as measured by the score for pain in the biopsied knee joint were also evaluated.

RESULTS

The immunohistologic features were not dependent on disease duration. We found a positive correlation between the scores for knee pain and the semiquantitative scores for the number of macrophages, as well as the expression of interleukin-6 and tumor necrosis factor alpha, whereas the correlation with the scores for CD4+ T cells was negative. Multivariate analysis showed that these correlations were highly statistically significant (P < 0.003).

CONCLUSION

The results do not support the view that inflammatory mechanisms in the synovial tissues of RA patients differ between early and late stages of the disease. The findings presented here are consistent with the concept that early RA is the result of a synovitis process of longer duration and that macrophage-derived cytokines play an important role in maintaining the clinical signs of inflammation.

T cell response to Epstein-Barr virus transactivators in chronic rheumatoid arthritis

Rheumatoid arthritis is a multistep disorder associated with autoimmune features of yet unknown etiology. Implication of viruses such as Epstein-Barr virus (EBV) in rheumatoid arthritis pathogenesis has been suspected on the basis of several indirect observations, but thus far, a direct link between EBV and rheumatoid arthritis has not been provided. Here we show that a large fraction of T cells infiltrating affected joints from a patient with chronic rheumatoid arthritis recognizes two EBV transactivators (BZLF1 and BMLF1) in a major histocompatibility complex-restricted fashion. Responses to these EBV antigens by synovial lymphocytes from several other chronic rheumatoid arthritis patients were readily detectable. Thus these results suggest a direct contribution of EBV to chronic rheumatoid arthritis pathogenesis. They also demonstrate for the first time the occurrence of T cell responses against EBV transactivating factors, which might be central in the control of virus reactivation.

Autoreactivity to human heat-shock protein 60 predicts disease remission in oligoarticular juvenile rheumatoid arthritis

OBJECTIVE

To determine whether T lymphocyte reactivity to endogenous human hsp60 plays a regulatory role in the course of oligoarticular juvenile rheumatoid arthritis (JRA).

METHODS

A prospective, longitudinal study of T cell reactivity to HSP in 15 patients with newly diagnosed HLA-B27 negative oligoarticular JRA was performed. Results were compared with those in a group of 20 patients with newly diagnosed polyarticular or systemic JRA or with acute arthritis caused by other systemic diseases or viral infections, as well as with those in a group of 9 healthy control subjects.

RESULTS

In 86% of the patients with oligoarticular JRA (13 of 15), significant T lymphocyte proliferative responses to hsp60 were found in peripheral blood mononuclear cells and/or synovial fluid mononuclear cells within 3 months after the onset of arthritis. Only 5% of the patients in the rheumatologic disease control group (1 of 20) showed such positivity. All patients with oligoarticular JRA and positive responses to human hsp60 developed a remission of their disease within 12 weeks. During this period of remission, blood samples were taken from 8 patients and showed significantly lower and even negative responses to hsp60, compared with active disease, when all 8 patients had good responses.

CONCLUSION

The results show that significant proliferative responses to human hsp60 can be found early in the course of oligoarticular JRA. Furthermore, these responses correlate with disease activity in such a manner that T cell reactivity to human hsp60 seems to be associated with disease remission.

Anti-Hsp65 antibodies recognize M proteins of group A streptococci

Group A streptococcal M protein and the mycobacterial heat shock protein, hsp65, are strong bacterial immunogens that have been linked to arthritis and autoimmunity. Recent evidence has shown that streptococcal arthritis and adjuvant arthritis may be related to epitopes shared between group A streptococci and hsp65. We investigated the possibility that immunological similarities were shared between streptococcal M protein and hsp65. Antibodies against the 65-kDa heat shock protein of Mycobacterium tuberculosis were tested for reactivity with group A streptococci and purified recombinant M proteins (rM5 and rM6). Rabbit polyclonal anti-hsp65 serum was highly reactive with M type 5 Streptococcus pyogenes and rM5 and rM6 proteins in an enzyme-linked immunosorbent assay (ELISA). A mouse anti-hsp65 monoclonal antibody (MAb), IIC8, reacted with streptococcal M types 5, 6, 19, 24, and 49 in an ELISA but showed no reactivity with an isogenic streptococcal mutant which did not express M protein. Anti-hsp65 MAb IIC8 recognized rM5 and rM6 proteins in the ELISA, and MAbs IIC8 and IIH9 reacted strongly with rM6 protein in Western immunoblots. The binding of M protein by anti-hsp65 MAbs was shown to be inhibited by both hsp65 and M protein. These data show that anti-hsp65 antibodies recognize streptococcal M proteins.

Rheumatoid factor, anti-heat shock protein (65 kDa) antibodies and anti-nuclear antibodies in equine joint diseases

To consider the hypothesis that autoimmune mechanisms may contribute to the pathology of equine joint diseases, 3 autoimmune responses were assayed in sera and synovial fluids. IgM-rheumatoid factor and antibodies to heat shock protein 65 kDa were determined by ELISA; anti-nuclear antibodies were assayed by indirect immunofluorescence to whole cell nuclear components. All parameters showed only modest increases, if any and not in a pattern related to disease, although some statistically significant increases were detected. Group analysis showed significantly elevated synovial fluid IgM-rheumatoid factor (IgM-RF) in horses with OA (P < 0.01), traumatised joints (P < 0.01) and articular fractured bones (P < 0.001). There was no significantly increased IgM-RF in the sera of horses with joint disorders compared to control horses. Significantly raised anti-heat shock protein molecular weight 65 kDa (HSP65) antibodies were only found in the synovial fluids of the horses with traumatised joints (P < 0.001). No correlations were found between the synovial fluid and sera levels of IgM-RF or anti-HSP65 antibodies. Synovial fluid anti-HSP65 antibody and IgM-RF levels positively correlated in the OCD (P < 0.001), fracture (P < 0.01) and synovitis (P < 0.05) groups. As antibodies to HSP65 correlated with IgG concentrations in synovial fluids, it is not possible to draw conclusions on HSP roles in joint disease pathogenesis. No serum anti-nuclear antibodies (ANA) were detected by immunofluorescence using rat liver and a human epithelial cell line (HEp-2) as substrates.(ABSTRACT TRUNCATED AT 250 WORDS)