Evaluation of diagnostic and therapeutic delay in patients with rheumatoid arthritis and psoriatic arthritis.

OBJECTIVE: A monocentric cross-sectional study recruiting rheumatoid arthritis (RA) and psoriatic arthritis (PsA) patients residing in the Lazio region, Italy, to assess factors related to diagnostic delay and treatment accessibility. METHODS: Clinical/serological data, including the time between symptom onset, diagnosis, and the beginning of treatment, were collected. Residence, referral to a rheumatologic center, physician who made the diagnosis, and previous misdiagnosis were also evaluated. RESULTS: A higher diagnostic delay (p=0.003), and time between symptom onset and the start of I-line therapy (p=0.006) were observed in PsA compared to RA. A delayed start of II-line therapy was observed in RA compared to PsA (p=0.0007). Higher diagnostic delay (p=0.02), and time between symptom onset and the start of conventional synthetic disease-modifying antirheumatic drugs (csDMARDs) (p=0.02) were observed among residents of small-medium cities for both groups. Patients who have been diagnosed by another physician rather than a rheumatologist had a longer diagnostic delay (p=0.034) and a delayed start of I-line therapy (p=0.019). Patients who received a different previous diagnosis experienced greater diagnostic delay (p=0.03 and p=0.003) and time of start of csDMARDs (p=0.05 and p=0.01) compared with those receiving RA or PsA as the first diagnosis. PsA had a delay in starting targeted synthetic disease-modifying anti-rheumatic drugs (p=0.0004) compared to RA. Seronegative RA had delayed diagnosis (p=0.02) and beginning of therapies (p=0.03; p=0.04) compared to seropositive ones. CONCLUSIONS: According to our results, greater diagnostic delay was found in PsA compared to RA, in patients living in small-medium cities, in those who did not receive the diagnosis from a rheumatologist, in those who were previously misdiagnosed, and in seronegative RA.

Subclinical microvascular changes in ANCA-vasculitides: the role of optical coherence tomography angiography and nailfold capillaroscopy in the detection of disease-related damage.

BACKGROUND: Both cardiovascular and complement-mediated disorders might lead to microvascular damages in anti-neutrophil cytoplasm autoantibodies (ANCA)-associated vasculitides (AAV). We aimed at investigating, for the first time, subclinical microvascular abnormalities with non-invasive techniques in AAV patients by analyzing both retinal and nailfold capillary changes. Retinal plexi were investigated using optical coherence tomography angiography (OCT-A), while nailfold capillary changes by video-capillaroscopy (NVC). Potential correlations between microvessels' abnormalities and disease damage were also explored. METHODS: An observational study was conducted on consecutive patients who met the inclusion criteria of defined diagnosis of eosinophilic granulomatosis with polyangiitis (EGPA), granulomatosis with polyangiitis (GPA), and microscopic polyangiitis (MPA), age ≥ 18 ≤ 75 yrs, and no ophthalmological disorders. Disease activity was assessed by Birmingham Vasculitis Activity Score (BVAS), damage by Vasculitis Damage Index (VDI), and poorer prognosis by the Five Factor Score (FFS). Quantitative analysis of vessel density (VD) was performed by OCT-A in both superficial and deep capillary plexi. Figures and detailed analysis from NVC were performed for all subjects in the study. RESULTS: Included AAV patients (n = 23) were compared with 20 age/sex-matched healthy controls (HC). Retinal VD in superficial whole and parafoveal plexi resulted significantly decreased in AAV compared to HC (P = 0.02 and P = 0.01, respectively). Furthermore, deep whole and parafoveal vessel density was strongly reduced in AAV than HC (P ≤ 0.0001 for both). In AAV patients, significant inverse correlations occurred between VDI and OCTA-VD in both superficial (parafoveal, P = 0.03) and deep plexi (whole, P = 0.003, and parafoveal P = 0.02). Non-specific NVC pattern abnormalities occurred in 82% of AAV patients with a similar prevalence (75%) in HC. In AAV, common abnormalities were edema and tortuosity in a comparable distribution with HC. Correlations between NVC changes and OCT-A abnormalities have not been described. CONCLUSION: Subclinical microvascular retinal changes occur in patients with AAV and correlate with the disease-related damage. In this context, the OCT-A can represent a useful tool in the early detection of vascular damage. AAV patients present microvascular abnormalities at NVC, whose clinical relevance requires further studies.

Micronutrients deficiencies in patients with spondylarthritis: the potential immunometabolic crosstalk in disease phenotype.

OBJECTIVE: Micronutrient deficiencies (MNDs) are common among patients with certain chronic inflammatory diseases. They are associated with a pro-inflammatory status and co-morbidities. However, no studies have specifically investigated MNDs in Spondyloarthritis (SpA). This paper aimed at analyzing the occurrence of anemia and deficiencies of ferritin (Fe), vitamin D [25(OH)D], vitamin B12 (B12), and folic acid (FA) in SpA patients. The interplay of MNDs with age, gender, and metabolic abnormalities was also explored. PATIENTS AND METHODS: MNDs were evaluated in 220 SpA outpatients (137 females and 83 age-matched males) with psoriatic arthritis (PsA, n=110) and non-psoriatic SpA (n=110). Metabolic parameters were analyzed. Disease activity was assessed by either Disease Activity in PSoriatic Arthritis (DAPSA) or Ankylosing Spondylitis Disease Activity Score with C-Reactive Protein (ASDAS-CRP) as appropriate, while the functional status was evaluated using Health Assessment Questionnaire modified for SpA (HAQ-S). RESULTS: Anemia occurred in 13.6% of subjects of the study cohort and almost wholly in females (p=0.004). Females showed higher Fe deficiency (p=0.04) and lower Fe levels (p=0.0003) than males. Hemoglobin (Hb) resulted inversely related to age and CRP (p=0.01 and p=0.008) in male group. The 25(OH)D deficiency (≤20 ng/ml) was present in 23.2% of the cohort with a higher prevalence in males than females (p=0.02): moreover, 25(OH)D inversely correlated with disease duration (p=0.02) in males. The B12 deficiency (≤200 pmol/l) was rare (13.2%), while FA ≤4 ng/ml was frequent (22%) and associated with B12 deficiency in 31% of cases. SpA patients in moderate/high disease activity had higher Body Mass Index (BMI) (p=0.04) and HAQ-S (p<0.0001), as well as lower Hb (p=0.02), and Fe (p=0.03) than patients in remission/low disease activity (LDA). In patients with extra-articular manifestations, female sex was prevalent (F:M=2) and B12 levels were lower than in patients without (p=0.005). Interestingly, 25(OH)D was lower (p=0.04) and both BMI and HAQ-S (p=0.036 and p=0.01) were higher in patients without extra-articular involvement than patients with. CONCLUSIONS: Our findings documented a relevant prevalence of MNDs in SpA patients, and its strict interplay with gender and metabolic abnormalities by highlighting the role of MNDs in inflammatory-dependent dysmetabolism in SpA.

Gender equality in Rheumatology.

Not available.

TNFAIP3 Gene Polymorphisms in Three Common Autoimmune Diseases: Systemic Lupus Erythematosus, Rheumatoid Arthritis, and Primary Sjogren Syndrome-Association with Disease Susceptibility and Clinical Phenotypes in Italian Patients.

Autoimmune diseases (AIDs) are complex diseases characterized by persistent or recurrent inflammation, alteration of immune response, and production of specific autoantibodies. It is known that different AIDs share several susceptibility genetic loci. Tumor necrosis factor alpha inducible protein 3 (TNFAIP3) encodes the ubiquitin-modifying enzyme A20, which downregulates inflammation by restricting NF-κB, a transcription factor that regulates expression of various proinflammatory genes. Variants in TNFAIP3 gene have been described as associated with susceptibility to several AIDs. Here, we analyzed two TNFAIP3 polymorphisms in Italian patients with systemic lupus erythematosus (SLE), rheumatoid arthritis (RA), and primary Sjogren's syndrome (pSS), to verify if the genetic variability of TNFAIP3 gene is involved in genetic predisposition to AIDs also in the Italian population. We recruited 313 SLE patients, 256 RA patients, 195 pSS patients, and 236 healthy controls. Genotyping of rs2230926 and rs6920220 in TNFAIP3 gene was performed by an allelic discrimination assay. We carried out a case/control association study and a genotype/phenotype correlation analysis. A higher risk to develop SLE was observed for rs2230926 (P = 0.02, OR = 1.92). No association was observed between this SNP and the susceptibility to pSS or RA. However, the rs2230926 variant allele seems to confer a higher risk to develop lymphoma in pSS patients, while in RA patients, the presence of RF resulted significantly associated with the variant allele. Regarding the rs6920220 SNP, we observed a significant association of the variant allele with SLE (P = 0.03, OR = 1.53), pSS (P = 0.016, OR = 1.69), and RA (P = 0.0001, OR = 2.35) susceptibility. Furthermore, SLE patients carrying the variant allele showed a higher risk to develop pericarditis, pleurisy, and kidney complications. Our results support the importance of the TNFAIP3 gene variant role in the development of different autoimmune diseases in the Italian population and furtherly confirm a sharing of genetic predisposing factors among these three pathologies.

Histopathology of the skin in rheumatic diseases.

Rheumatological systemic autoimmune diseases, such as connective tissue diseases, rheumatoid arthritis or spondyloarthritis, are characterized by the presence of joint involvement associated with extra-articular manifestations. Among them, cutaneous diseases are often the most relevant and representative clinical manifestation, as in psoriatic arthritis, scleroderma or systemic lupus erythematosus. In this context, it is useful for rheumatologists to understand better skin diseases and their histopathological features. Evaluation of skin biopsy specimens can be helpful not only to confirm the diagnosis in both classic and clinically atypical variants, but also to improve further our knowledge of the pathogenetic mechanisms and the close link between skin and articular diseases. In this review, we discuss the clinical features, diagnostic evaluation and the histopathological features of skin manifestation of the most relevant rheumatological autoimmune diseases.

Serum thymosin α 1 levels in patients with chronic inflammatory autoimmune diseases.

Thymosin alpha 1 (Tα1) is a powerful modulator of immunity and inflammation. Despite years of studies, there are a few reports evaluating serum Tα1 in health and disease. We studied a cohort of healthy individuals in comparison with patients affected by chronic inflammatory autoimmune diseases. Sera from 120 blood donors (healthy controls, HC), 120 patients with psoriatic arthritis (PsA), 40 with rheumatoid arthritis (RA) and 40 with systemic lupus erythematosus (SLE), attending the Transfusion Medicine or the Rheumatology Clinic at the Policlinico Tor Vergata, Rome, Italy, were tested for Tα1 content by means of a commercial enzyme-linked immunosorbent assay (ELISA) kit. Data were analysed in relation to demographic and clinical characteristics of patients and controls. A gender difference was found in the HC group, where females had lower serum Tα1 levels than males (P < 0·0001). Patients had lower serum Tα1 levels than HC (P < 0·0001), the lowest were observed in PsA group (P < 0·0001 versus all the other groups). Among all patients, those who at the time of blood collection were taking disease-modifying anti-rheumatic drugs (DMARD) plus steroids had significantly higher Tα1 levels than those taking DMARD alone (P = 0·044) or no treatment (P < 0·0001), but not of those taking steroids alone (P = 0·280). However, whichever type of treatment was taken by the patients, serum Tα1 was still significantly lower than in HC and there was no treatment-related difference in PsA group. Further prospective studies are necessary to confirm and deepen these observations. They might improve our understanding on the regulatory role of Tα1 in health and disease and increase our knowledge of the pathogenesis of chronic inflammatory autoimmune diseases.

Polymorphisms in STAT-4, IL-10, PSORS1C1, PTPN2 and MIR146A genes are associated differently with prognostic factors in Italian patients affected by rheumatoid arthritis.

Rheumatoid arthritis (RA) is a systemic autoimmune disease resulting in chronic inflammation of the synovium and consequent cartilage and bone erosion. RA is associated strongly with the presence of rheumatoid factor (RF), and consists of clinical subsets of anti-citrullinated protein antibody (ACPA)-positive and -negative patients. This study was designed to evaluate whether relevant single nucleotide polymorphisms (SNPs) associated with RA and other autoimmune disorders are related to RF, ACPA and clinical phenotype in a cohort of biologic drugs naive Italian RA patients; 192 RA patients and 278 age-matched healthy controls were included. Clinical and laboratory data were registered. We analysed a total of 12 single nucleotide polymorphisms (SNPs) in signal transducer and activator of transcription-4 (STAT-4), interleukin (IL)-10, psoriasis susceptibility 1 candidate 1 (PSORS1C1), protein tyrosine phosphatase, non-receptor type 2 (PTPN2), endoplasmic reticulum aminopeptidase 1 (ERAP1), tumour necrosis factor receptor-associated 3 interacting protein 2 (TRAF3IP2) and microRNA 146a (MIR146A) genes by allelic discrimination assays. Case-control association studies and genotype/phenotype correlation analyses were performed. A higher risk to develop RA was observed for rs7574865 in the STAT-4 gene, while the rs1800872 in the IL-10 gene showed a protective effect. The presence of RF was associated significantly with rs1800872 variant in IL-10, while rs2910164 in MIR146A was protective. ACPA were associated significantly with rs7574865 in STAT-4. The SNP rs2233945 in the PSORS1C1 gene was protective regarding the presence of bone erosions, while rs2542151 in PTPN2 gene was associated with joint damage. Our results confirm that polymorphisms in STAT-4 and IL-10 genes confer susceptibility to RA. For the first time, we described that SNPs in PSORS1C1, PTPN2 and MIR146A genes were associated differently with a severe disease phenotype in terms of autoantibody status and radiographic damage in an Italian RA population.

Autoantibodies in inflammatory arthritis.

Rheumatoid arthritis (RA) is a systemic chronic inflammatory disease characterized by extensive synovitis resulting in erosions of articular cartilage and marginal bone with joint destruction. The lack of immunological tolerance in RA represents the first step toward the development of autoimmunity. Susceptible individuals, under the influence of environmental factors, such as tobacco smoke, and silica exposure, develop autoimmune phenomena that result in the presence of autoantibodies. HLA and non-HLA haplotypes play a major role in determining the development of specific autoantibodies differentiating anti-citrullinated antibodies (ACPA)-positive and negative RA patients. Rheumatoid factor (RF) and ACPA are the serological markers for RA, and during the preclinical immunological phase, autoantibody titers increase with a progressive spread of ACPA antigens repertoire. The presence of ACPA represents an independent risk factor for developing RA in patients with undifferentiated arthritis or arthralgia. Moreover, anti-CarP antibodies have been identified in patients with RA as well as in individuals before the onset of clinical symptoms of RA. Several autoantibodies mainly targeting post-translational modified proteins have been investigated as possible biomarkers to improve the early diagnosis, prognosis and response to therapy in RA patients. Psoriatic arthritis (PsA) is distinguished from RA by infrequent positivity for RF and ACPA, together with other distinctive clinical features. Actually, specific autoantibodies have not been described. Recently, anti-CarP antibodies have been reported in sera from PsA patients with active disease. Further investigations on autoantibodies showing high specificity and sensibility as well as relevant correlation with disease severity, progression, and response to therapy are awaited in inflammatory arthritides.

Peripheral blood natural killer cells and mild thyroid abnormalities in women with reproductive failure.

Abnormalities in peripheral blood natural killer (NK) cells have been reported in women with primary infertility and recurrent spontaneous abortion (RSA) and several studies have been presented to define cutoff values for abnormal peripheral blood NK cell levels in this context. Elevated levels of NK cells were observed in infertile/RSA women in the presence of thyroid autoimmunity (TAI), while no studies have been carried out, to date, on NK cells in infertile/RSA women with non-autoimmune thyroid diseases. The contribution of this study is two-fold: (1) the evaluation of peripheral blood NK cell levels in a cohort of infertile/RSA women, in order to confirm related data from the literature; and (2) the assessment of NK cell levels in the presence of both TAI and subclinical hypothyroidism (SCH) in order to explore the possibility that the association between NK cells and thyroid function is not only restricted to TAI but also to SCH. In a retrospective study, 259 age-matched women (primary infertility [n = 49], primary RSA [n = 145], and secondary RSA [n = 65]) were evaluated for CD56+CD16+NK cells by flow cytometry. Women were stratified according to thyroid status: TAI, SCH, and without thyroid diseases (ET). Fertile women (n = 45) were used as controls. Infertile/RSA women showed higher mean NK cell levels than controls. The cutoff value determining the abnormal NK cell levels resulted ⩾15% in all the groups of women. Among the infertile/RSA women, SCH resulted the most frequently associated thyroid disorder while no difference resulted in the prevalence of TAI and ET women between patients and controls. A higher prevalence of women with NK cell levels ⩾15% was observed in infertile/RSA women with SCH when compared to TAI/ET women. According to our data, NK cell assessment could be used as a diagnostic tool in women with reproductive failure and we suggest that the possible association between NK cell levels and thyroid function can be described not only in the presence of TAI but also in the presence of non-autoimmune thyroid disorders.

The interplay between inflammation and metabolism in rheumatoid arthritis.

Rheumatoid arthritis (RA) is a chronic autoimmune disease characterized by extensive synovitis resulting in erosions of articular cartilage and marginal bone that lead to joint destruction. The autoimmune process in RA depends on the activation of immune cells, which use intracellular kinases to respond to external stimuli such as cytokines, immune complexes, and antigens. An intricate cytokine network participates in inflammation and in perpetuation of disease by positive feedback loops promoting systemic disorder. The widespread systemic effects mediated by pro-inflammatory cytokines in RA impact on metabolism and in particular in lymphocyte metabolism. Moreover, RA pathobiology seems to share some common pathways with atherosclerosis, including endothelial dysfunction that is related to underlying chronic inflammation. The extent of the metabolic changes and the types of metabolites seen may be good markers of cytokine-mediated inflammatory processes in RA. Altered metabolic fingerprints may be useful in predicting the development of RA in patients with early arthritis as well as in the evaluation of the treatment response. Evidence supports the role of metabolomic analysis as a novel and nontargeted approach for identifying potential biomarkers and for improving the clinical and therapeutical management of patients with chronic inflammatory diseases. Here, we review the metabolic changes occurring in the pathogenesis of RA as well as the implication of the metabolic features in the treatment response.

Distribution of interleukin-10 family cytokines in serum and synovial fluid of patients with inflammatory arthritis reveals different contribution to systemic and joint inflammation.

Evidence exists that interleukin (IL)-10 family cytokines may be involved in the pathogenesis of rheumatoid arthritis (RA). We sought to determine whether or not these cytokines are involved in psoriatic arthritis (PsA). We conducted a prospective study on patients with PsA, RA and osteoarthritis (OA); healthy controls (HC) were also included. We analysed IL-20, IL-24 and IL-19 serum and synovial fluid (SF) levels and change of serum levels following treatment with biological agents. IL-20 serum levels were increased in PsA and RA compared with OA patients and HC and with matched SF levels. IL-24 serum levels in PsA, RA and OA patients were higher than those in HC and also with respect to matched SF in PsA. IL-19 serum levels were higher in HC and OA compared with PsA and RA patients; IL-19 SF levels were higher in PsA and RA compared with OA patients, and in PsA compared with RA patients. PsA and RA patients showed a reduction of IL-19 serum levels after biological treatment. Therefore, IL-19 seems to be involved mainly in the joint inflammation, whereas IL-20 and IL-24 appear to participate mainly in the systemic responses. These findings may further the comprehension of the contribution of these cytokines to the inflammatory response involved in chronic arthritis, as well as to the development of novel therapeutic strategies.

Restoration of peripheral blood natural killer and B cell levels in patients affected by rheumatoid and psoriatic arthritis during etanercept treatment.

Etanercept (ETN) is an anti-tumour necrosis factor (TNF)-α agent used in rheumatoid arthritis (RA) and psoriatic arthritis (PsA). Few studies focused on the effects of anti-TNF-α on peripheral blood cells. We aimed to evaluate peripheral blood cells in RA and PsA patients during ETN treatment and to explore their relationships with disease activity. RA (n = 82) and PsA (n = 32) patients who started ETN were included into the study and evaluated prospectively before the beginning of ETN therapy and after 14, 22, 54 and 102 weeks. Patients were studied in terms of disease activity score on 28 joints (DAS28), clinical response and laboratory findings. Natural killer (NK) cells, B cells and T cells were characterized by immunophenotyping. Both the RA and the PsA patients showed reduced NK and B cell count before ETN treatment compared with controls. A negative correlation was demonstrated between DAS28 and B cell count in RA patients at baseline. Sustained significant increase of NK and B cells up to normal levels was observed in RA and PsA patients along ETN treatment. Increase of NK cell count was associated with a good-moderate clinical response to ETN in both RA and PsA patients. During ETN treatment peripheral blood NK and B cells levels were restored in RA and PsA patients. Correlations between NK and B cells with disease activity were observed, suggesting that those effects could be mediated by ETN treatment.

Complement system in psoriatic arthritis: a useful marker in response prediction and monitoring of anti-TNF treatment.

OBJECTIVES: Treatment with anti-TNF agents is well established in psoriatic arthritis (PsA). Anti-TNF agents are capable of modulating complement activity in vitro but there are no data on the in vivo effect. Anti-TNF have high costs and potential risks, thus, there is an urgent need for accurate predictors of response. We aimed at studying the usefulness of erythrocyte-sedimentation-rate (ESR), C-reactive protein (CRP), and complement for response prediction and monitoring of anti-TNF treatment in PsA patients. METHODS: Fifty-five patients were included consecutively before starting etanercept or adalimumab. ESR, CRP, plasma complement C3, C4, and C3 and B cleavage fragments were evaluated at baseline and after 22 weeks of anti-TNF treatment. Disease activity was measured with DAS28 and response to therapy with EULAR criteria. Complement was evaluated at baseline in 30 healthy subjects as well. RESULTS: At baseline, C3 and C4 levels were significantly higher than in controls (C3 126.9±22 vs. 110±25 mg/dl, p=0.000002; C4 31.2±9.2 vs. 22.7±8.3 mg/dl, p=0.0003). After anti-TNF therapy, C3 and C4 levels were significantly reduced to normalization (p=0.0009 and 0.0005, respectively) and ESR, CRP and DAS28 showed a significant reduction (p=0.002, 0.004 and 0.0001, respectively). Split products of C3 and B were not observed at baseline and after 22 weeks. Higher baseline C3 levels were associated with EULAR non-response (p=0.011). CONCLUSIONS: PsA patients with moderate to severe disease show elevated C3 and C4 levels, reverted by anti-TNF treatment. High C3 may be considered a hallmark of inflammation and C3 revealed the highest predictive value for response to anti-TNF.

Complement system and rheumatoid arthritis: relationships with autoantibodies, serological, clinical features, and anti-TNF treatment.

Autoantibodies (rheumatoid factor, RF; anti-citrullinated-protein antibodies, ACPA) and complement system are involved in rheumatoid arthritis (RA). ACPA and anti-TNF agents are capable of in vitro modulating complement activity. We investigated the relationships between complement, autoantibodies, and anti-TNF treatment in vivo. One-hundred fourteen RA patients (89F/25M), diagnosed according to 1987 ACR criteria, and 30 healthy controls were enrolled. Serological analysis included ESR, CRP, complement C3, C4 and CH50, RF and ACPA (ELISA, cut-off>20 U/ml). Split-products (SP) of C3 and B were studied by immunoelectrophoresis/counterimmunoelectrophoresis. Seventy-six patients started anti-TNF treatment and were studied at baseline and after 22 weeks. Disease activity was measured with DAS28 and response to therapy with EULAR criteria. At baseline, RA patients showed significantly higher levels of C3 and C4 than controls (C3 127.9±26.5 vs 110±25 mg/dl, P=0.0012; C4 29.7±10.2 vs 22.7±8.3mg/dl, P=0.0003). No differences in C3, C4 and CH50 levels were observed between ACPA+ (n=76) and ACPA- (n=38) patients. After 22 weeks of anti-TNF, C3, C4 and RF were significantly reduced (P<0.003, <0.005 and <0.04, respectively) and RF changes showed negative correlation with CH50. SP of C3 and B were observed neither at baseline nor after 22 weeks. DAS28 significantly improved after 22 weeks. Patients showing higher baseline C3 or lower reduction of C3 levels after 22 weeks had a worse EULAR outcome (X2=22.793, P<0.001). RF levels seem to correlate with complement CH50. The presence of high levels of C3 in RA patients may reflect a pro-inflammatory status and represent a negative prognostic factor for anti-TNF therapy.

Dissecting the contribution of innate and antigen-specific pathways to the breach of self-tolerance observed in a murine model of arthritis.

BACKGROUND: The relative roles of innate immunity and antigen-specific T cells in rheumatoid arthritis remain controversial. Previous studies demonstrated that T-helper type 1 cells of irrelevant antigen specificity (ovalbumin) induced a transient arthritis in BALB/c mice, which recapitulates many of the pre-articular and articular features of human disease and is associated with the emergence of autoreactive T and B-cell responses to joint-specific antigens. However, the mechanisms underlying this phenomenon were unclear. OBJECTIVES: The aim of this study was to dissect the relative contribution of innate and heterologous antigen-specific pathways to the breach of self-tolerance and pathology observed in this model and how this may result from modified T and B-cell interactions. METHODS: To address this issue, experimental arthritis was elicited either by a non-specific inflammatory stimulus alone, by activation of T cells of an irrelevant specificity or a combination of both. RESULTS: The non-specific inflammatory response generated by lipopolysaccharide led to articular inflammation and cartilage erosion, but did not break tolerance to joint-specific antigens. In contrast, local activation of T cells of an irrelevant specificity produced a similar pathological picture but, in addition, induced T-cell responses to unrelated joint-specific antigens with associated activation of autoreactive B cells. These effects could be further potentiated by the addition of lipopolysaccharide. CONCLUSION: These data demonstrate that non-specific inflammation alone is insufficient to breach self-tolerance. In contrast, T cells of an irrelevant specificity, when triggered locally in an antigen-specific manner, can breach self-tolerance leading to arthritis and autoantibody production, which can then be amplified in a non-specific manner.

Anti-lysobisphosphatidic acid antibodies in patients with antiphospholipid syndrome and systemic lupus erythematosus.

Lyso(bis)phosphatidic acid (LBPA) is a novel antigenic target in anti-phospholipid syndrome (APS) and antibodies directed against LBPA (aLBPA) have been detected in sera from APS patients. In this study we first evaluated aLBPA in comparison with the most widely used methods (i.e. anticardiolipin [(aCL)-enzyme-linked immunosorbent assay (ELISA)] and antibeta-2-glycoprotein-I antibodies (abeta(2)-GPI-ELISA) utilized to detect antiphospholipid antibodies in patients with primary or secondary APS, systemic lupus erythematosus, chronic HCV infection and healthy subjects. We then assessed the relationship between aLBPA, lupus anticoagulant (LAC) and the main clinical manifestations of APS. Finally, we evaluated the presence of 'pure' (i.e. beta(2)-GPI-independent) aLBPA in patients with APS and controls. The results indicate that aLBPA as well as abeta(2)-GPI display higher specificity but lower sensitivity for APS compared to aCL. Moreover, serum aLBPA correlate closely with aCL and abeta(2)-GPI in APS patients and are strictly associated with LAC positivity. We demonstrate that beta(2)-GPI binds to LBPA with affinity similar to CL, and antibodies able to react with phosholipid-protein complex exist; however, 'pure' aLBPA can also be detected in sera of APS patients. Altogether these data confirm that LBPA may be an antigenic target in APS and that aLBPA are serological markers of APS with similar sensitivity and specificity compared to abeta(2)-GPI. However, the clinical utility of aLBPA detection alone or in combination with aCL and/or abeta(2)-GPI remains to be elucidated in larger and longitudinal studies.

Synthesis of a cytosine nucleoside of 2-amino-2-deoxy-beta-D-xylofuranose.

1-(2-Amino-2-deoxy-beta-D-xylofuranosyl)cytosine (13) was synthesized by three routes: (a) coupling of 2-deoxy-3,5-di-O-p-nitrobenzoyl-2-(trifluoroacetamido)-D-xylofuranosyl chloride (5) with 2,4-dimethoxypyrimidine and subsequent treatment with methanolic ammonia, (b) coupling of 5 with 4-N-acetyl-2-O,4-N-bis(trimethylsilyl)cytosine followed by treatment with methanolic ammonia, and (c) thiation of 1-[3,5-di-O-acetyl-2-deoxy-2-(trifluoroacetamido)-beta-D-xylofuranosyl]uracil (6) by treatment with phosphorus pentasulfide in pyridine followed by amination of the resulting 4-thionucleoside 12 with metanolic ammonia. The best yield was obtained via route (a).