Pulmonary arterial hypertension: guidelines and unmet clinical needs.

The term pulmonary arterial hypertension (PAH) identifies a heterogeneous group of diseases characterized by a progressive increase in pulmonary arterial resistance (PVR), which causes a significant burden in terms of quality of life, right heart failure and premature death. The pathogenesis of PAH is not completely clear: the remodeling of the small pulmonary vessels is crucial, causing an increase in the resistance of the pulmonary circle. Its diagnosis is based on cardiac catheterization of the right heart. According to the present hemodynamic definition of pulmonary hypertension (PH) proposed by the Guidelines of the European Society of Cardiology/European Respiratory Society (ESC-ERS), the mean pulmonary arterial pressure (mPAP) values are ≥25 mmHg. In case of PAH, apart from an mPAP value ≥25 mmHg, patients must have a >3 Wood units increase in PVR and normal pressure values of the left heart. PH is a pathophysiological condition observed in more than 40 different diseases, while PAH is a primary disease of the pulmonary bloodstream potentially treatable with specific drugs. PAH is a severe complication of systemic sclerosis (SSc) affecting about 10% of the patients. Due to the devastating nature of SSc-PAH, there is a clear need to systematically adopt appropriate screening programs. In fact, despite awareness of the negative impact of SSc-PAH on quality of life and survival, as well as on the severity of lung function, at the moment standardized and shared guidelines and/or screening programs for the diagnosis and the subsequent early treatment of PAH in SSc are not available. The aim of the present paper is to highlight the lights and shadows of SSc-PAH, unraveling the unmet clinical needs on this topic with a proposal of clinical-diagnostic and therapeutic guidelines.

Secondary hypogammaglobulinemia in Waldmann's disease treated with subcutaneous immunoglobulins.

Primary intestinal lymphangiectasia (PIL) is rare disorder characterized by congenital malformation or obstruction of intestinal lymphatic drainage; it is responsible for protein losing enteropathy leading to lymphopenia, hypoalbuminemia and hypogammaglobulinemia. A low-fat diet associated with medium-chain triglyceride supplementation is the cornerstone of PIL management. The administration of intravenous immunoglobulins does not always lead to satisfactory plasma levels and therefore the replacement therapy with immunoglobulins is controversial. We describe here the case of a patient with PIL and severe hypogammaglobulinemia treated with immunoglobulins. The striking aspect of this case is the clinical and serological benefit obtained with the subcutaneous compared to the intravenous immunoglobulins administration.

Infections and autoimmunity: role of human cytomegalovirus in autoimmune endothelial cell damage.

Molecular mimicry between infectious agents and normal human host cell proteins represents one of the possible mechanisms responsible for autoimmunity. Among infectious agents, human cytomegalovirus (HCMV) is an ideal candidate for involvement in autoimmune disorders because of its lifelong persistence through periods of reactivation and latency and because of the extensive manipulation of innate and adaptive immunity. HCMV has been implicated in the pathogenesis of vascular damage in systemic sclerosis (SSc) and atherosclerosis. Based on our data, which demonstrate a cause-and-effect relationship between HCMV and endothelial cell aggression in SSc and atherosclerosis, we propose that immune responses to particular HCMV proteins may result in autoaggression through a mechanism of molecular mimicry of normally expressed endothelial cell surface molecules.

Safety of rituximab in the routine treatment of rheumatoid arthritis in Italy in patients refractory to anti-TNFa drugs: results from the observational retrospective-prospective RUBINO study.

The paper reports the results from the observational retrospective-prospective RUBINO study conducted in Italy to assess the safety of rituximab in the treatment of rheumatoid arthritis (RA) in routine clinical practice. The percentage of patients who manifested at least one grade 3 or 4 adverse event (AE) assessed by the Common Terminology Criteria for Adverse Events version 3.0 (CTCAE v.3) during the observation period (primary objective) was evaluated. The percentage of patients manifesting a severe AE (SAE), clinical response to rituximab treatment, clinical remission according to disease activity score for 28 joints (DAS28) criteria, markers of disease and quality of life were also assessed. Fifty-three Italian rheumatology centers took part in the study. Patients with a diagnosis of RA and inadequate response to anti-tumor necrosis factor b (anti-TNFa) drugs were enrolled. Participating patients had previously received at least one cycle of rituximab, and treatment was still ongoing at the time of recruitment. Out of 205 patients enrolled, 60% manifested no form of AE, 14.2% had at least one grade 3 or 4 AE, and 11.2% patients reported an SAE. The overall percentage of patients manifesting AEs (40%) was lower compared to the DANCER (81% and 85%), REFLEX (85%) and RESET (85% and 69%) studies, but higher than that observed in the CERERRA registry (from 10.2% to 13.9%). This difference may be due to the shorter observation period applied in the CERERRA registry (only 12 months) compared to the RUBINO study (up to 3 years). All parameters of RA activity (erythrocyte sedimentation rate, C-reactive protein, health assessment questionnaire score, DAS28) improved significantly during the study.

Gene expression profiling in dermatitis herpetiformis skin lesions.

Dermatitis herpetiformis (DH) is an autoimmune blistering skin disease associated with gluten-sensitive enteropathy (CD). In order to investigate the pathogenesis of skin lesions at molecular level, we analysed the gene expression profiles in skin biopsies from 6 CD patients with DH and 6 healthy controls using Affymetrix HG-U133A 2.0 arrays. 486 genes were differentially expressed in DH skin compared to normal skin: 225 were upregulated and 261 were downregulated. Consistently with the autoimmune origin of DH, functional classification of the differentially expressed genes (DEGs) indicates a B- and T-cell immune response (LAG3, TRAF5, DPP4, and NT5E). In addition, gene modulation provides evidence for a local inflammatory response (IL8, PTGFR, FSTL1, IFI16, BDKRD2, and NAMPT) with concomitant leukocyte recruitment (CCL5, ENPP2), endothelial cell activation, and neutrophil extravasation (SELL, SELE). DEGs also indicate overproduction of matrix proteases (MMP9, ADAM9, and ADAM19) and proteolytic enzymes (CTSG, ELA2, CPA3, TPSB2, and CMA1) that may contribute to epidermal splitting and blister formation. Finally, we observed modulation of genes involved in cell growth inhibition (CGREF1, PA2G4, and PPP2R1B), increased apoptosis (FAS, TNFSF10, and BASP1), and reduced adhesion at the dermal epidermal junction (PLEC1, ITGB4, and LAMA5). In conclusion, our results identify genes that are involved in the pathogenesis of DH skin lesions.

Antiflagellin antibodies recognize the autoantigens Toll-Like Receptor 5 and Pals 1-associated tight junction protein and induce monocytes activation and increased intestinal permeability in Crohn's disease.

BACKGROUND AND OBJECTIVES: Bacterial flagellin is considered an important antigen in Crohn's disease (CD) as it activates innate immunity through Toll-Like Receptor 5 (TLR5) engagement and induces an elevated adaptive immune response. Little is known about the presence of an autoimmune process in CD. We aimed to identify pathogenically relevant autoantigen targets in CD. METHODS: We screened a random peptide library with pooled sera of patients with active CD. Transepithelial flux of [3H] mannitol in T84 human intestinal epithelial cell line was used to study the epithelial barrier function. Monocyte activation was evaluated by surface expression of activation markers and by production of pro-inflammatory cytokines. Gene modulation of T84 cells exposed to antipeptide antibodies was analysed by gene array. RESULTS: We identified a peptide that shares homology with Salmonella typhimurium flagellin and with self-antigens such as TLR5 and cell junction protein, Pals 1-associated tight junction protein. The affinity-purified antipeptide antibodies recognized the self-antigens and induced increased intestinal epithelial cell permeability. Moreover, the antibodies induced monocyte activation upon binding TLR5. Finally, in cultured intestinal cells (T84) the purified antibodies induced the modulation of clusters of proinflammatory genes similar to the one induced by the engagement of TLR5 by its natural ligand flagellin. CONCLUSIONS: Antibodies directed against an immunodominant peptide of flagellin recognize self-antigens and are functionally active suggesting the presence of an autoimmune process that can both facilitate loss of tolerance to intestinal microflora by increasing cell permeability and amplify the innate immunity involvement through a novel mechanism of TLR5 activation.

Schnitzler's syndrome treated successfully with intravenous pulse cyclophosphamide.

Schnitzler's syndrome is a rare clinical condition characterized by chronic urticaria, intermittent fever, bone pain, arthralgia or arthritis, and monoclonal immunoglobulin M (IgM) gammopathy. Here we describe the case of a 48-year-old Italian female with a long history of arthralgia, leucocytosis, spiking fever, and chronic urticaria with severe pruritus. The IgM-kappa monoclonal component in the serum and bone densification on conventional X-ray with hyperfixation on bone technetium scanning at the distal part of the femurs and at the proximal part of the tibias were detected 4 years after the onset of the symptoms. After many ineffective treatments, the use of pulse cyclophosphamide (CPX) resulted in complete remission of the disease that is still lasting after a 2-year follow-up.

Efficacy of intravenous immunoglobulin in chronic idiopathic pericarditis: report of four cases.

Human intravenous immunoglobulins (hIVIgs) are used in two broad categories of diseases: immunodeficiency and autoimmunity. Among the immune-mediated diseases hIVIgs are of benefit in idiopathic thrombocytopenic purpura, autoimmune hemolytic anemia, and dermatomyositis. Chronic idiopathic pericarditis (CIP) is a chronic disease of unknown origin characterized by recurrent episodes of pericardial inflammation. The cause of the recurrence is unknown, although in some cases it may be traced to a viral infection and to the presence of antimyocardial antibodies. Since a viral infection can induce an autoimmune process through a mechanism of molecular mimicry, and since the optimal therapy for prevention of the recurrences has not been established, we reasoned that treatment with hIVIgs could be beneficial in our patients unresponsive to previous immunosuppressive therapies. We describe four patients affected by CIP treated with monthly high-dose hIVIgs (0.4 g/kg daily for 5 consecutive days) for five times followed by administration every 2 months. Three of the four patients could permanently discontinue steroid therapy and are still in remission after years of follow-up. Our experience suggests that hIVIgs therapy may be a useful and safe treatment for CIP in steroid-dependent patients.

In chronic idiopathic urticaria autoantibodies against Fc epsilonRII/CD23 induce histamine release via eosinophil activation.

BACKGROUND: Chronic idiopathic urticaria is a common skin disorder characterized by recurrent, transitory, itchy weals for more than 6 weeks. An autoimmune origin has been suggested based on the findings of auto-antibodies (Abs) directed against either the alpha subunit of the high-affinity IgE receptor or the IgE molecule in nearly half of the patients. OBJECTIVE: To identify other autoantigen targets in patients with chronic idiopathic urticaria. METHODS: We used pooled IgG derived from 133 patients with chronic idiopathic urticaria to screen a random peptide library to identify disease-relevant autoantigen peptides. Among the identified peptides, one was recognized by the vast majority of patients' sera. Abs against this peptide were affinity purified from the patients' sera and assayed for their ability to induce histamine release from basophils. RESULTS: We identified a peptide that showed similarity with the low-affinity IgE receptor (Fc epsilonRII/CD23) expressed on lymphomonocytes and eosinophils. Anti-peptide IgG Abs purified from the patients' sera bound cell surface CD23 and were able to induce histamine release from basophils. This effect appeared to be mediated by the release of major basic protein from eosinophils upon engagement of CD23. The same effects were obtained with the sera from mice immunized with the CD23 peptide. CONCLUSION: Our results indicate that patients with chronic idiopathic urticaria have Abs against CD23 and that eosinophils, which infiltrate the skin of these patients, play a crucial role in maintaining the disease through the release of major basic protein upon engagement of the low-affinity IgE receptor by such auto-Abs.

A1298C methylenetetrahydrofolate reductase mutation and coronary artery disease: relationships with C677T polymorphism and homocysteine/folate metabolism.

5, 10-Methylenetetrahydrofolate reductase (MTHFR) is a crucial enzyme in homocysteine/methionine metabolism. The most-studied C677T polymorphism in the MTHFR gene results in a thermolabile variant with reduced activity, and is associated with increased levels of total plasma homocysteine, a risk factor for coronary artery disease. A new mutation in the MTHFR gene (A1298C) has also been reported to lower enzyme activity. Whether A1298C is a risk factor for coronary artery disease, separately or in combination with C677T, and/or relative to total plasma homocysteine and folate status, is unclear to date. We evaluated this hypothesis in 470 angiographically characterized subjects, 302 with coronary artery disease, and 168 with normal coronary arteries. The frequency of the 1298C allele was 0.33 and that of combined heterozygosity 0.315. No difference was found in the frequency of the genotypes or when analyzed for combined heterozygosity between patients with coronary artery disease and normals. Independent of folate status, the 1298C allele was not associated with increased total plasma homocysteine. No additional effect of A1298C on total plasma homocysteine was observed in 148 combined heterozygotes compared with 98 heterozygotes for the C677T alone. These findings do not support a major role for the A1298C mutation in homocysteine metabolism and emphasize the hypothesis that MTHFR genotypes may interfere with coronary artery disease risk only when an unbalanced nutritional status leads to raised total plasma homocysteine levels.

Clinical, biochemical and molecular findings in a series of families with hereditary hyperferritinaemia-cataract syndrome.

Hereditary hyperferritinaemia-cataract syndrome (HHCS) is an autosomal dominant disease caused by mutations in the iron responsive element (IRE) of the l-ferritin gene. Despite the elucidation of the genetic basis, the overall clinical spectrum of HHCS has been less well studied as, to date, only individual case reports have been described. Therefore, we studied a total of 62 patients in 14 unrelated families, with nine different mutations. No relevant symptoms other than visual impairment were found to be associated with the syndrome. A marked phenotypic variability was observed, particularly with regard to ocular involvement (i.e. age range at which cataract was diagnosed in 16 subjects with the C39T: 6-40 years). Similarly, serum ferritin levels varied substantially also within subjects sharing the same mutation (i.e. range for the A40G: 700-2412 microg/l). We followed an HHCS newborn in whom well-defined lens opacities were not detectable either at birth or at 1 year. The lens ferritin content was analysed in two subjects who underwent cataract surgery at different ages, with different cataract morphology. Values were similar and about 1500-fold higher than in controls. These observations suggest that: (i) in HHCS the cataract is not necessarily congenital; (ii) in addition to the IRE genotype, other genetic or environmental factors may modulate the phenotype, especially the severity of the cataract.