Plasma from patients undergoing allogeneic hematopoietic stem cell transplantation promotes NETOSIS in vitro and correlates with inflammatory parameters and clinical severity.

Introduction: NETosis, the mechanism by which neutrophils release extracellular traps (NETs), is closely related to inflammation. During the allogeneic hematopoietic stem cell transplantation (allo-HSCT), different stimuli can induce NETs formation. Inflammation and endothelial injury have been associated with acute graft-versus-host disease (aGVHD) and complications after allo-HSCT. We focus on the study of NETosis and its relation with cytokines, hematological and biochemical parameters and clinical outcomes before, during and after allo-HSCT. Methods: We evaluate the capacity of plasma samples from allo-HSCT patients to induce NETosis, in a cell culture model. Plasma samples from patients undergoing allo-HSCT had a stronger higher NETs induction capacity (NETsIC) than plasma from healthy donors throughout the transplantation process. An optimal cut-off value by ROC analysis was established to discriminate between patients whose plasma triggered NETosis (NETs+IC group) and those who did not (NETs-IC group). Results: Prior to conditioning treatment, the capacity of plasma samples to trigger NETosis was significantly correlated with the Endothelial Activation and Stress Index (EASIX) score. At day 5 after transplant, patients with a positive NETsIC had higher interleukin (IL)-6 and C-reactive protein (CRP) levels and also a higher Modified EASIX score (M-EASIX) than patients with a negative NETsIC. EASIX and M-EASIX scores seek to determine inflammation and endothelium damage, therefore it could indicate a heightened immune response and inflammation in the group of patients with a positive NETsIC. Cytokine levels, specifically IL-8 and IL-6, significantly increased after allo-HSCT with peak levels reached on day 10 after graft infusion. Only, IL-10 and IL-6 levels were significantly higher in patients with a positive NETsIC. In our small cohort, higher IL-6 and IL-8 levels were related to early severe complications (before day 15 after transplant). Discussion: Although early complications were not related to NETosis by itself, NETosis could predict overall non-specific but clinically significant complications during the full patient admission. In summary, NETosis can be directly induced by plasma from allo-HSCT patients and NETsIC was associated with clinical indicators of disease severity, cytokines levels and inflammatory markers.

Hyperinflammatory Immune Response in COVID-19: Host Genetic Factors in Pyrin Inflammasome and Immunity to Virus in a Spanish Population from Majorca Island.

The hyperinflammatory response caused by SARS-CoV-2 infection contributes to its severity, and many critically ill patients show features of cytokine storm (CS) syndrome. We investigated, by next-generation sequencing, 24 causative genes of primary immunodeficiencies whose defect predisposes to CS. We studied two cohorts with extreme phenotypes of SARS-CoV-2 infection: critical/severe hyperinflammatory patients (H-P) and asymptomatic patients (AM-risk-P) with a high risk (older age) to severe COVID-19. To explore inborn errors of the immunity, we investigated the presence of pathogenic or rare variants, and to identify COVID-19 severity-associated markers, we compared the allele frequencies of common genetic polymorphisms between our two cohorts. We found: 1 H-P carries the likely pathogenic variant c.887-2 A>C in the IRF7 gene and 5 H-P carries variants in the MEFV gene, whose role in the pathogenicity of the familial Mediterranean fever (FMF) disease is controversial. The common polymorphism analysis showed three potential risk biomarkers for developing the hyperinflammatory response: the homozygous haplotype rs1231123A/A-rs1231122A/A in MEFV gene, the IFNAR2 p.Phe8Ser variant, and the CARMIL2 p.Val181Met variant. The combined analysis showed an increased risk of developing severe COVID-19 in patients that had at least one of our genetic risk markers (odds ratio (OR) = 6.2 (95% CI) (2.430-16.20)).

Clinical manifestations and approach to the management of patients with common variable immunodeficiency and liver disease.

Purpose: The clinical spectrum of common variable immunodeficiency (CVID) includes predisposition to infections, autoimmune/inflammatory complications and malignancy. Liver disease is developed by a proportion of patients with CVID, but limited evidence is available about its prevalence, pathogenesis and prognostic outcome. This lack of evidence leads to the absence of guidelines in clinical practice. In this study, we aimed at defining the characteristics, course and management of this CVID complication in Spain. Methods: Spanish reference centers were invited to complete a cross-sectional survey. Thirty-eight patients with CVID-related liver disease from different hospitals were evaluated by a retrospective clinical course review. Results: In this cohort, abnormal liver function and thrombocytopenia were found in most of the patients (95% and 79% respectively), in keeping with the higher incidence of abnormal liver imaging and splenomegaly. The most common histological findings included nodular regenerative hyperplasia (NRH) and lymphocytic infiltration, which have been associated with portal hypertension (PHTN) leading to a poorer prognosis. Autoimmune/inflammatory complications occurred in 82% of the CVID patients that developed liver disease and 52% of the patients treated with immunomodulators showed a reduction in the liver function tests' abnormalities during treatment. Among the experts that conducted the survey, there was 80% or more consensus that the workup of CVID-related liver disease requires liver profile, abdominal ultrasound and transient elastography. The majority agreed that liver biopsy should be essential for diagnosis. There was 94% consensus that endoscopic studies should be performed in the presence of PHTN. However, there was 89% consensus that there is insufficient evidence on the management of these patients. Conclusion: Liver disease varies in severity and may contribute substantially to morbidity and mortality in patients with CVID. Hence the importance of close follow-up and screening of this CVID complication to prompt early targeted intervention. Further research is needed to evaluate the pathophysiology of liver disease in patients with CVID to identify personalized treatment options. This study emphasizes the urgent need to develop international guidelines for the diagnosis and management of this CVID complication.