Antiphospholipid antibodies and COVID-19 thrombotic vasculopathy: one swallow does not make a summer

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8-Chloro-Cyclic AMP and Protein Kinase A I-Selective Cyclic AMP Analogs Inhibit Cancer Cell Growth through Different Mechanisms

Cyclic AMP (cAMP) inhibits the proliferation of several tumor cells. We previously reported an antiproliferative effect of PKA I-selective cAMP analogs (8-PIP-cAMP and 8-HA-cAMP) on two human cancer cell lines of different origin. 8-Cl-cAMP, another cAMP analog with known antiproliferative properties, has been investigated as a potential anticancer drug. Here, we compared the antiproliferative effect of 8-Cl-cAMP and the PKA I-selective cAMP analogs in three human cancer cell lines (ARO, NPA and WRO). 8-Cl-cAMP and the PKA I-selective cAMP analogs had similarly potent antiproliferative effects on the BRAF-positive ARO and NPA cells, but not on the BRAF-negative WRO cells, in which only 8-Cl-cAMP consistently inhibited cell growth. While treatment with the PKA I-selective cAMP analogs was associated with growth arrest, 8-Cl-cAMP induced apoptosis. To further investigate the actions of 8-Cl-cAMP and the PKA I-selective cAMP analogs, we analyzed their effects on signaling pathways involved in cell proliferation and apoptosis. Interestingly, the PKA I-selective cAMP analogs, but not 8-Cl-cAMP, inhibited ERK phosphorylation, whereas 8-Cl-cAMP alone induced a progressive phosphorylation of the p38 mitogen-activated protein kinase (MAPK), via activation of AMPK by its metabolite 8-Cl-adenosine. Importantly, the pro-apoptotic effect of 8-Cl-cAMP could be largely prevented by pharmacological inhibition of the p38 MAPK. Altogether, these data suggest that 8-Cl-cAMP and the PKA I-selective cAMP analogs, though of comparable antiproliferative potency, act through different mechanisms. PKA I-selective cAMP analogs induce growth arrest in cells carrying the BRAF oncogene, whereas 8-Cl-cAMP induce apoptosis, apparently through activation of the p38 MAPK pathway

Pathogenic Role of Complement in Antiphospholipid Syndrome and Therapeutic Implications

Antiphospholipid syndrome (APS) is an acquired autoimmune disease characterized by thromboembolic events, pregnancy morbidity, and the presence of antiphospholipid (aPL) antibodies. There is sound evidence that aPL act as pathogenic autoantibodies being responsible for vascular clots and miscarriages. However, the exact mechanisms involved in the clinical manifestations of the syndrome are still a matter of investigation. In particular, while vascular thrombosis is apparently not associated with inflammation, the pathogenesis of miscarriages can be explained only in part by the aPL-mediated hypercoagulable state and additional non-thrombotic effects, including placental inflammation, have been described. Despite this difference, evidence obtained from animal models and studies in APS patients support the conclusion that complement activation is a common denominator in both vascular and obstetric APS. Tissue-bound aPL rather than circulating aPL-beta2 glycoprotein I immune complexes seem to be responsible for the activation of the classical and the alternative complement pathways. The critical role of complement is supported by the finding that complement-deficient animals are protected from the pathogenic effect of passively infused aPL and similar results have been obtained blocking complement activation. Moreover, elevated levels of complement activation products in the absence of abnormalities in regulatory molecules have been found in the plasma of APS patients, strongly suggesting that the activation of complement cascade is the result of aPL binding to the target antigen rather than of a defective regulation. Placental complement deposits represent a further marker of complement activation both in animals and in patients, and there is also some suggestive evidence that complement activation products are deposited in the affected vessels. The aim of this review is to analyze the state of the art of complement involvement in the pathogenesis of APS in order to provide insights into the role of this system as predictive biomarker for the clinical manifestations and as therapeutic target

New insight into antiphospholipid syndrome: antibodies to \u3b22glycoprotein I-domain 5 fail to induce thrombi in rats

Clinical studies have reported different diagnostic/predictive values of antibodies to domain 1 or 4/5 of \u3b22glycoproteinI in terms of risk of thrombosis and pregnancy complications in patients with antiphospholipid syndrome. To obtain direct evidence for the pathogenic role of anti-domain 1 or anti-domain 4/5 antibodies, we analysed the in vivo pro-coagulant effect of two groups of 5 serum IgG each reacting selectively with domain 1 or domain 5 in LPS-treated rats. Antibody-induced thrombus formation in mesenteric vessels was followed by intravital microscopy and vascular deposition of \u3b22glycoproteinI, human IgG and C3 was analyzed by immunofluorescence. Five serum IgG with undetectable anti-\u3b22glycoproteinI antibodies served as controls. All the anti-domain 1 positive IgG exhibited potent pro-coagulant activity while the anti-domain 5 positive and the negative control IgG failed to promote blood clot and vessels occlusion. A stronger granular deposit of IgG/C3 was found on the mesenteric endothelium of rats treated with anti-domain 1 antibodies, as opposed to a mild linear IgG staining and absence of C3 observed in rats receiving anti-domain 5 antibodies. Purified anti-domain 5 IgG, unlike anti-domain 1 IgG, did not recognize cardiolipin-bound \u3b22glycoprotein I while able to interact with fluid-phase \u3b22glycoproteinI. These findings may explain the failure of anti-domain 5 antibodies to exhibit in vivo thrombogenic effect and the interaction of these antibodies with circulating \u3b22glycoproteinI suggest their potential competitive role with the pro-coagulant activity of anti-domain 1 antibodies. These data aim at better defining really at risk patients for more appropriate treatments to avoid recurrences and disability

1079-102 Correlation between norepinephrine and epinephrine myocardial spillover and tumor necrosis factor-alpha in conventional versus off-pump coronary artery bypass surgery

Background: Complete revascularization obtained by coronary artery bypass surgery does not prevent long term left ventricular remodeling and heart failure development. Periprocedural events linked to different surgical techniques, such as cardiopulmonary bypass with cardioplegic arrest (CABG) versus off-pump procedures may trigger an irreversible microvascular dysfunction or myocytes necrosis and apoptosis. Methods: To test this hypothesis we measured norepinephrine and epinephrine coronary sinus and aortic spillover before and after surgery, simultaneously with Tumor Necrosis Factor-alpha (TNF-alpha) measurements in 30 patients randomized to CABG (n=15), or off-pump (n=15) coronary surgery. Plasma catecholamines were assessed by high performance liquid chromatography and TNF-alpha by ELISA. Results: Norepinephrine and epinephrine spillover was similar in the two groups before surgery, being 1.38\ub10.62 and 1.08\ub10.45, respectively. After surgery norepinephrine spillover was 1.43\ub10.56, 0.72\ub10.49 in CABG and off-pump, respectively (P<0.05 CABG versus off-pump, means \ub1SD ). Epinephrine spillover was 1.27\ub10.16 and 0.65\ub10.15 respectively (P<0.05, CABG versus off-pump). TNF-alpha significantly increased only in CABG patients being 22.17\ub16.79 and 35.4\ub15.98, pg/mL, before and after surgery (P<0.05), respectively. After surgery norepinephrine spillover correlated with TNF-alpha levels (P=0.01, R=0.553). Conclusions: Patients undergoing off-pump interventions showed significantly lower catecholamines spillover as compared to CABG, suggesting that the off-pump technique may result less invasive, not only for a lower local and whole body inflammatory response but also for a lower sympathetic drive. For the first time in humans we have detected an increase in epinephrine-spillover after cardiac surgery. Further studies are necessary to evaluate if the short-term advantages observed after off-pump coronary surgery translate into a long-term attenuation of left ventricular remodeling and in the prevention of heart failure progression

Pathogenic role of complement in antiphospholipid syndrome and therapeutic implications

Antiphospholipid syndrome (APS) is an acquired autoimmune disease characterized by thromboembolic events, pregnancy morbidity, and the presence of antiphospholipid (aPL) antibodies. There is sound evidence that aPL act as pathogenic autoantibodies being responsible for vascular clots and miscarriages. However, the exact mechanisms involved in the clinical manifestations of the syndrome are still a matter of investigation. In particular, while vascular thrombosis is apparently not associated with inflammation, the pathogenesis of miscarriages can be explained only in part by the aPL-mediated hypercoagulable state and additional non-thrombotic effects, including placental inflammation, have been described. Despite this difference, evidence obtained from animal models and studies in APS patients support the conclusion that complement activation is a common denominator in both vascular and obstetric APS. Tissue-bound aPL rather than circulating aPL-beta2 glycoprotein I immune complexes seem to be responsible for the activation of the classical and the alternative complement pathways. The critical role of complement is supported by the finding that complement-deficient animals are protected from the pathogenic effect of passively infused aPL and similar results have been obtained blocking complement activation. Moreover, elevated levels of complement activation products in the absence of abnormalities in regulatory molecules have been found in the plasma of APS patients, strongly suggesting that the activation of complement cascade is the result of aPL binding to the target antigen rather than of a defective regulation. Placental complement deposits represent a further marker of complement activation both in animals and in patients, and there is also some suggestive evidence that complement activation products are deposited in the affected vessels. The aim of this review is to analyze the state of the art of complement involvement in the pathogenesis of APS in order to provide insights into the role of this system as predictive biomarker for the clinical manifestations and as therapeutic target

A new molecular classification to drive precision treatment strategies in primary Sjögren’s syndrome

There is currently no approved treatment for primary Sjögren's syndrome, a disease that primarily affects adult women. The difficulty in developing effective therapies is -in part- because of the heterogeneity in the clinical manifestation and pathophysiology of the disease. Finding common molecular signatures among patient subgroups could improve our understanding of disease etiology, and facilitate the development of targeted therapeutics. Here, we report, in a cross-sectional cohort, a molecular classification scheme for Sjögren's syndrome patients based on the multi-omic profiling of whole blood samples from a European cohort of over 300 patients, and a similar number of age and gender-matched healthy volunteers. Using transcriptomic, genomic, epigenetic, cytokine expression and flow cytometry data, combined with clinical parameters, we identify four groups of patients with distinct patterns of immune dysregulation. The biomarkers we identify can be used by machine learning classifiers to sort future patients into subgroups, allowing the re-evaluation of response to treatments in clinical trials

Integrative Analysis Reveals a Molecular Stratification of Systemic Autoimmune Diseases

Objective Clinical heterogeneity, a hallmark of systemic autoimmune diseases, impedes early diagnosis and effective treatment, issues that may be addressed if patients could be classified into groups defined by molecular pattern. This study was undertaken to identify molecular clusters for reclassifying systemic autoimmune diseases independently of clinical diagnosis. Methods Unsupervised clustering of integrated whole blood transcriptome and methylome cross-sectional data on 955 patients with 7 systemic autoimmune diseases and 267 healthy controls was undertaken. In addition, an inception cohort was prospectively followed up for 6 or 14 months to validate the results and analyze whether or not cluster assignment changed over time. Results Four clusters were identified and validated. Three were pathologic, representing “inflammatory,” “lymphoid,” and “interferon” patterns. Each included all diagnoses and was defined by genetic, clinical, serologic, and cellular features. A fourth cluster with no specific molecular pattern was associated with low disease activity and included healthy controls. A longitudinal and independent inception cohort showed a relapse–remission pattern, where patients remained in their pathologic cluster, moving only to the healthy one, thus showing that the molecular clusters remained stable over time and that single pathogenic molecular signatures characterized each individual patient. Conclusion Patients with systemic autoimmune diseases can be jointly stratified into 3 stable disease clusters with specific molecular patterns differentiating different molecular disease mechanisms. These results have important implications for future clinical trials and the study of nonresponse to therapy, marking a paradigm shift in our view of systemic autoimmune diseases

Serum profiling identifies CCL8, CXCL13, and IL-1RA as markers of active disease in patients with systemic lupus erythematosus

IntroductionSystemic lupus erythematosus (SLE) is a clinically heterogeneous disease that presents a challenge for clinicians. To identify potential biomarkers for diagnosis and disease activity in SLE, we investigated a selected yet broad panel of cytokines and autoantibodies in patients with SLE, healthy controls (HC), and patients with other autoimmune diseases (AIDs).MethodsSerum samples from 422 SLE patients, 546 HC, and 1223 other AIDs were analysed within the frame of the European PRECISESADS project (NTC02890121). Cytokine levels were determined using Luminex panels, and autoantibodies using different immunoassays.ResultsOf the 83 cytokines analysed, 29 differed significantly between patients with SLE and HC. Specifically, CCL8, CXCL13, and IL-1RA levels were elevated in patients with active, but not inactive, SLE versus HC, as well as in patients with SLE versus other AIDs. The levels of these cytokines also correlated with SLE Disease Activity Index 2000 (SLEDAI-2K) scores, among five other cytokines. Overall, the occurrence of autoantibodies was similar across SLEDAI-2K organ domains, and the correlations between autoantibodies and activity in different organ domains were weak.DiscussionOur findings suggest that, upon validation, CCL8, CXCL13, and IL-1RA could serve as promising serum biomarkers of activity in SLE