Angela Ceribelli

MicroRNAs in systemic rheumatic diseases

MicroRNAs (miRNAs) are endogenous, non-coding, single-stranded RNAs about 21 nucleotides in length. miRNAs have been shown to regulate gene expression and thus influence a wide range of physiological and pathological processes. Moreover, they are detected in a variety of sources, including tissues, serum, and other body fluids, such as saliva. The role of miRNAs is evident in various malignant and nonmalignant diseases, and there is accumulating evidence also for an important role of miRNAs in systemic rheumatic diseases. Abnormal expression of miRNAs has been reported in autoimmune diseases, mainly in systemic lupus erythematosus and rheumatoid arthritis. miRNAs can be aberrantly expressed even in the different stages of disease progression, allowing miRNAs to be important biomarkers, to help understand the pathogenesis of the disease, and to monitor disease activity and effects of treatment. Different groups have demonstrated a link between miRNA expression and disease activity, as in the case of renal flares in lupus patients. Moreover, miRNAs are emerging as potential targets for new therapeutic strategies of autoimmune disorders. Taken together, recent data demonstrate that miRNAs can influence mechanisms involved in the pathogenesis, relapse, and specific organ involvement of autoimmune diseases. The ultimate goal is the identification of a miRNA target or targets that could be manipulated through specific therapies, aiming at activation or inhibition of specific miRNAs responsible for the development of disease.

Anti-MJ/NXP-2 autoantibody specificity in a cohort of adult Italian patients with polymyositis/dermatomyositis

IntroductionAutoantibodies in patients with polymyositis/dermatomyositis (PM/DM) are associated with unique subsets, clinical course and outcome. Anti-MJ antibodies, which recognize the nuclear protein NXP-2/MORC3, are reported in ~25% of juvenile DM. Prevalence and clinical significance of anti-MJ antibodies in adult Italian PM/DM patients were studied.MethodsSera from 58 consecutive adult Italian PM/DM patients were analyzed by immunoprecipitation of 35S-labeled K562 cells extract, ELISA (anti-MJ, Jo-1), Western blot and indirect immunofluorescence. Clinical associations were analyzed using information from medical charts.ResultsAnti-MJ antibodies were the most prevalent specificity (17%) found mainly in DM (30%, 8 cases) vs 8% of PM (2 cases, P = 0.02). Comparing 10 anti-MJ (+) vs 48 anti-MJ (-) cases, DM was more common (P = 0.03), and age at onset was younger in anti-MJ (+) (P = 0.0006). In anti-MJ (+), heliotrope rash (P = 0.01) and calcinosis (P = 0.09) were more frequent. None of them had heart or lung involvement, or malignancy. Myopathy in anti-MJ (+) patients responded well to therapy and none of them had elevated CPK at last visit (0% vs 25% in anti-MJ (-)). Only 60% of anti-MJ (+) showed immunofluorescent nuclear dots staining, despite PML localization of NXP-2/MORC3.ConclusionsAnti-MJ antibodies are the most frequent specificity in our cohort of adult Italian PM/DM. Anti-MJ (+) were associated with young onset DM, calcinosis, no internal organ involvement and good response of myopathy to therapy. Anti-MJ reported in juvenile DM is also found in adult PM/DM, and could be a new useful biomarker.

MicroRNAs in rheumatoid arthritis

Rheumatoid arthritis (RA) is a chronic and severe autoimmune disease that affects joint tissues, bone, and cartilage. However, the pathogenesis of RA is still unclear. Autoantibodies such as rheumatoid factor and anti‐cyclic citrullinated peptide are useful tools for early diagnosis, monitoring disease activity, and predicting prognosis. Recently, many groups have focused their attention on the role of microRNAs in the pathogenesis of RA, as well as a potential biomarker to monitor RA. In fact, the expression of some microRNAs, such as miR‐146a, is upregulated in different cell types and tissues in RA patients. MicroRNAs in RA could also be considered as possible future targets for new therapeutic approaches.

Malignancies in Italian patients with systemic sclerosis positive for anti-RNA polymerase III antibodies.

Objective. To evaluate the frequency of malignancies in Italian patients with systemic sclerosis (SSc) and anti-RNA polymerase III (RNAP III), antitopoisomerase I (topo I), or anticentromere antibodies (ACA); and to characterize the temporal relationship between the 2 diseases, in order to confirm data suggesting a close temporal relationship between the onset of SSc and malignancy in American patients with anti-RNAP III antibodies. Methods. From a cohort of 466 consecutive SSc patients, 360 Italians with isolated positivity for anti-RNAP III (n = 16), anti-topo I (n = 101), or ACA (n = 243) were identified. Malignancy cases were divided according to their relationship with SSc onset into 3 categories: preceding, synchronous with, or metachronous to the onset of SSc (diagnosed more than 6 months before; 6 months before to 12 months after; and more than 12 months after onset of SSc, respectively). Results. Malignancies were more frequent in the anti-RNAP III group (7/16 patients), than in the anti-topo I (11/101) and ACA groups (21/243) (p < 0.001). This difference was accounted for by the number of patients with cancer synchronous to the onset of SSc (3/16 in the anti-RNAP III group vs 0/101 in the anti-topo I and 1/243 in the ACA group; p < 0.001), whereas neither the number of malignancies preceding nor those metachronous to the onset of SSc was significantly different between the groups. Conclusion. In a cohort of Italian patients with SSc we observed a significant association between malignancies synchronous to SSc onset and positivity for anti-RNAP III antibodies, similar to that described in American patients with SSc.

MicroRNA-146a in autoimmunity and innate immune responses

MicroRNA (miRNA) are approximately 22 nucleotide single-stranded RNA that regulate the stability of target messenger RNA by selective binding to specific sites at the 3′-untranslated regions (UTR). This triggers repression in translation and mRNA degradation. It has been estimated that approximately 60% of all mRNA are under the control of miRNA. Among the known hundreds of miRNA, some are considered master regulators controlling either a single or multiple cellular pathways. Some miRNA are known to affect development and cell differentiation, while others are implicated in immunity and autoimmune diseases. A very interesting example is miR-146a, which has been reported to be downregulated in systemic lupus erythematosus and upregulated in rheumatoid arthritis (RA). Several groups have recently focused their attention on miRNA in the pathogenesis of RA. Interestingly, the expression of miR-146a is upregulated in different cell types and tissues in RA patients. miRNA in RA could also be considered as possible future targets for new therapeutic approaches. This discussion will focus on the current understanding in the function of miR-146a in endotoxin tolerance and cross-tolerance, and how it may contribute to modulate the overproduction of known pathogenic cytokines, such as tumour necrosis factor α.

MicroRNAs and autoimmunity.

The role of microRNAs (miRNAs) in the regulation of many physiological and pathological processes has been intensely studied in recent years. Some miRNAs, such as miR-146a and miR-182, play a dominant role in the regulation of the innate and adaptive immune responses, respectively. Many miRNAs are reportedly deregulated in autoimmune diseases, but miR-146a in particular seems to be consistently altered. The overexpression or underexpression of miRNAs can influence specific targets and pathways, leading to autoimmune disease phenotypes, and this is supported also by some in vivo studies. Targeting miRNAs could represent a valid future therapeutic option for autoimmune diseases.

Treatment with etanercept in six patients with chronic hepatitis C infection and systemic autoimmune diseases

OBJECTIVE To describe the clinical and immunologic features of 6 patients with rheumatic disease and Hepatitis C Virus (HCV) chronic infection, treated with anti-TNF alpha drugs. PATIENTS AND METHODS Six patients, with repeated positive serology for HCV infection, were affected by Rheumatoid arthritis (RA) (4 cases), Psoriatic Arthritis (PsA) and Polymyositis in one case each. They started anti-TNFalpha treatment (Etanercept), due to a previous failure of combination of different immunosuppressants (Methotrexate, Sulfasalazine, Cyclosporine, Hydroxychloroquine). RESULTS Patients (3 female and 3 males) showed a mean age at disease onset of 50.6 years (SD 14.5) and a mean disease duration of 12.5 years (SD: 8.8). Etanercept (dosage of 50 mg weekly) was continued for a median period of 14 months. Patients affected by RA and PsA achieved a good clinical response, with a significant reduction of DAS28 during treatment (p: 0.0001). No patient received any specific therapy for HCV infection. Elevated HCV-RNA titres were recorded in 5 cases at start of Etanercept. No significant increase was observed during anti-TNF alpha treatment. No cases of hepatic failure were recorded. CONCLUSION Anti-TNF alpha therapy showed to be effective, safe and well tolerated in the setting of HCV infection.

Treatment of lupus skin involvement with quinacrine and hydroxychloroquine

To evaluate the efficacy of hydroxychloroquine (HCQ) and quinacrine (Qn) association, at two different dosages, in treatment of lupus skin lesions not responding to HCQ alone. Thirty-four patients, affected by cutaneous and systemic lupus erythematosus, were retrospectively analysed. They were treated by HCQ (5 mg/Kg/qd) and Qn with two regimens: 100 mg/qd (29 cases) and 50 mg/qd (5 cases). Discoid lupus erythematosus (19 cases), acute malar rash (6 cases), chilblain lupus (4 cases) showed a significant improvement with combination therapy (P = 0.009, P = 0.019, and P = 0.04, respectively). Ten patients with subacute cutaneous lupus showed a partial response, whereas lupus profundus didn’t improve. The same overall response rate was recorded comparing two Qn regimens, but subjects taking 100 mg/qd improved more rapidly than the others (P = 0.001). Ten patients developed side effects, mainly represented by skin yellowish discolouration. Depression and severe headache with nausea, which were globally recorded in two cases, led to drug withdrawal. One additional case of hepatitis was recorded in a patient with preexisting Hepatitis C virus (HCV) infection. Combination of HCQ and Qn is rapidly effective at 100 mg/qd and well tolerated in the treatment of lupus skin lesions unresponsive to HCQ alone.

Prevalence and clinical associations of anti-Ku antibodies in systemic autoimmune diseases

We retrospectively analysed the prevalence and clinical features associated to anti-Ku antibodies in patients affected by different autoimmune diseases. Anti-Ku antibodies are detected in 147 sera out of 7239 anti-ENA positive sera (2%). They are found in 2% of patients with systemic sclerosis (SSc) (8 out of 379), 1.8% of systemic lupus erythematosus (SLE) (7 out of 372) and 1.8% of undifferentiated connective tissue disease (UCTD) (9 out of 496) and more rarely in Sjögren Syndrome and rheumatoid arthritis. Most of anti-Ku positive patients were affected by UCTD and overlap syndromes, including polymyositis, SSc and SLE. Interstitial lung disease, myositis, articular symptoms, Raynaud’s phenomenon and sicca represents the main clinical features detected in our cohort. The rate and severity of pulmonary disease is similar to those found in other SSc patients. Isolated anti-Ku were detected in about 47% of sera. No clinical differences were observed between these patients and subjects with multiple anti-nuclear specificities. However, anti-Ku are usually detected in association with other serological markers in SLE and Sjögren Syndrome, while they occurred isolated in SSc and polymyositis.

Gender and ethnicity differences in the prevalence of scleroderma-related autoantibodies

Autoantibodies to topoisomerase I (topo I), RNA polymerase III (RNAPIII), centromere, U3RNP/fibrillarin, Th, PM-Scl, and U1RNP found in scleroderma (SSc) are associated with unique clinical subsets. The effects of race and gender on autoantibody prevalence and clinical manifestations were examined. Autoantibodies in sera from 105 SSc (include 75 Caucasian, 24 African-American, 6 others; 89 females and 16 males) were analyzed by immunofluorescence and immunoprecipitation. Clinical information was from database. SSc-related autoantibodies seldom coexist except for anti-topo I and anti-U1RNP. Anti-topo I (35% vs 15%), anti-U3RNP (30% vs 3%, p = 0.0005), and anti-U1RNP (30% vs 13%) were more common in African-Americans vs Caucasians. Anti-centromere (17%) and anti-PM-Scl (only in 8% of female) were found only in Caucasians. In race/gender combination, all three African-American males had anti-topo I (p = 0.04). Anti-U3RNP (35% vs 3%, p = 0.0005) and anti-U1RNP were common in African-American females. In African-American, all nucleolar dominant staining sera had anti-U3RNP; nuclear pattern was topo I (50%), U1RNP (19%), and RNAPIII (13%). In Caucasian, nucleolar was anti-Th (43%) and PM-Scl (29%); nuclear pattern was RNAPIII (29%), topo I (24%), and U1RNP (18%). Anti-topo I, anti-RNAPIII, and anti-U3RNP were associated with diffuse SSc while anti-centromere, anti-Th, and anti-U1 with limited disease. Proximal scleroderma was less common in African-American with anti-topo I (38% vs 91% in Caucasian, p = 0.04). The production of SSc-related autoantibodies is gender and race dependent, and this can be highly relevant in understanding their clinical significance.