Clinical Immunology

iPLA 2 Activation Mediates Granular Exocytosis and Corrects Microbicidal Defects in ROS-Deficient and CGD Human Neutrophils Abstract Purpose The ubiquitous calcium–independent phospholipase A2 enzyme (iPLA2) is inhibited by calmodulin binding and known to be responsible for phospholipid remodeling housekeeping functions including granule exocytosis–associated membrane fusion in normal human neutrophils. We evaluate in human neutrophils the iPLA2 secretagogue effects using normal neutrophils, where reactive oxygen species (ROS) generation has been blocked by diphenyleneiodonium, as well as in neutrophils from chronic granulomatous disease (CGD) patients. Methods Neutrophils were pretreated with W7, a calmodulin inhibitor known to activate iPLA2 and exocytosis of granules, and vesicles as well as intra- and extra-microbicidal activity against Staphylococcus aureus and Aspergillus fumigatus were evaluated. Results W7 increases exocytosis of primary, secondary, and tertiary granules and vesicles and improves neutrophil microbicidal activity against S. aureus and A. fumigatus. Conclusions In neutrophils, calmodulin-mediated iPLA2 inhibition controls granule and vesicle exocytosis in the phagosome and in the extracellular microenvironment. Relieving iPLA2 inhibition results in increased exocytosis of primary, secondary, and tertiary granules and secretory vesicles with correction of defective intracellular and extracellular microbicidal activity. In CGD patients presenting ROS defective production, this increase in the non-oxidative killing pathway partially corrects their microbicidal defects.

Different Phenotypic Presentations of X-Linked Lymphoproliferative Disease in Siblings with Identical Mutations

Efficacy and Adverse Events During Janus Kinase Inhibitor Treatment of SAVI Syndrome Abstract Objectives Mutations affecting the TMEM173 gene cause STING-associated vasculopathy with onset in infancy (SAVI). No standard immunosuppressive treatment approach is able to control disease progression in patients with SAVI. We studied the efficacy and safety of targeting type I IFN signaling with the Janus kinase inhibitor, ruxolitinib. Methods We used DNA sequencing to identify mutations in TMEM173 in patients with peripheral blood type I IFN signature. The JAK1/2 inhibitor ruxolitinib was administered on an off-label basis. Results We identified three patients with SAVI presenting with skin involvement and progressive severe interstitial lung disease. Indirect echocardiographic signs of pulmonary hypertension were present in one case. Following treatment with ruxolitinib, we observed improvements of respiratory function including increased forced vital capacity in two patients, with discontinuation of oxygen therapy and resolution of echocardiographic abnormalities in one case. Efficacy was persistent in one patient and only transitory in the other two patients. Clinical control of skin complications was obtained, and one patient discontinued steroid treatment. One patient, who presented with kidney involvement, showed resolution of hematuria. One patient experienced increased recurrence of severe viral respiratory infections. Monitoring of peripheral blood type I interferon signature during ruxolitinib treatment did not show a stable decrease. Conclusions We conclude that targeting type I IFN receptor signaling may represent a promising therapeutic option for a subset of patients with SAVI syndrome and severe lung involvement. However, the occurrence of viral respiratory infection might represent an important cautionary note for the application of such form of treatment.

Clinical and Laboratory Features of 184 Italian Pediatric Patients Affected with Selective IgA Deficiency (SIgAD): a Longitudinal Single-Center Study Abstract Purpose Selective IgA deficiency (SIgAD) is the most common humoral primary immunodeficiency. Long-term follow-up data in large cohort of pediatric patients are scarce. Methods We report on a single-center cohort of 184 pediatric patients affected with selective IgA deficiency and describe the characteristics at diagnosis and during follow-up. Results Respiratory infections were the most common clinical finding leading to the initial diagnosis (62%). Positive family history for antibody deficiencies (selective IgA deficiency, common variable immunodeficiency) led to SIgAD diagnosis in 16% of cases. During follow-up, while the incidence of respiratory infections was not particularly high, gastrointestinal symptoms were reported in 27% of patients. Allergic manifestations were found in 23% at diagnosis and an additional 16% of patients during follow-up, leading to a prevalence of atopy of 39% among SIgAD patients. Autoimmune manifestations, excluding celiac disease, were found in 9% of affected patients during follow-up. Celiac disease was found in a high prevalence (14%). Increase of serum IgA levels to partial deficiency (9%) and normal serum levels for age (4%) was observed during follow-up. A small percentage of patients (2%) progressed to common variable immunodeficiency (CVID). Conclusions In conclusion, this is the first study to describe a large single-center pediatric cohort of patients affected with SIgAD, revealing that overall most patients do well with regard to infections. Many develop CD, at a rate much higher than the general population. A few normalize their IgA levels. A few progress to CVID. Thus, careful follow-up is suggested to diagnose and treat potential complications earlier for avoiding potential morbidities.

Autoinflammation Masquerading as Autoimmunity in an Adult with Heterozygous p.E250K PSTPIP1 Mutation

Successful Lung Transplantation in a Patient with Chronic Granulomatous Disease

Enterovirus-Associated HLH: Addition of Anakinra to IVIG and Corticosteroids

Defining Primary Selective IgM Deficiency

Variable Responses to Tocilizumab in Four Patients with Schnitzler Syndrome

Role of Allogeneic Hematopoietic Stem Cell Transplant for Chronic Granulomatous Disease (CGD): a Report of the United States Immunodeficiency Network Abstract Purpose Chronic granulomatous disease (CGD) is a primary immunodeficiency for which allogeneic hematopoietic stem cell transplant (HSCT) offers potential cure. Direct comparison of HSCT to non-HSCT management in the North American population was performed to identify clinical factors associated with overall survival (OS) and transplant-related survival (TRS). Methods Retrospective review of CGD subjects enrolled in the United States Immunodeficiency Network. Survival was estimated by the Kaplan-Meier method and modeled by proportional hazards regression. Results We identified 507 patients (66% CYBB mutants) diagnosed in 1953–2016. Fifty underwent allogeneic HSCT. Median follow-up was 9.1 years after diagnosis (0–45.8 years). OS was negatively associated with CYBBmutation (HR = 6.25; p = 0.034) and not associated with HSCT (88% v. 85% ± HCT) (HR = 1.26; p = 0.65). Transplant at ≤ 14 years old was associated with improved TRS (93% v. 82% at T + 60 months) (HR = − 4.51; p = 0.035). Patients transplanted before 15 years old had fewer severe infections pre-HSCT (mean 0.95 v. 2.13; p = 0.047). No mortality was reported in patients receiving stem cells from matched siblings. Infection incidence declined post-HSCT in subjects with greater than or equal to four infections pre-HSCT (p = 0.0010). Compared to non-HSCT patients ≥ 15 years old, post-transplant survivors had higher mean performance score (93.2 v. 85.9; p = 0.0039) and lower frequency of disability (11% v. 52%; p = 0.014). Conclusion Allogeneic HSCT was associated with reduced infection incidence and improved functional performance, but not with a change in overall survival. Transplant-related survival was elevated in patients undergoing HSCT before 15 years old. Consider HSCT prior to late adolescence in patients with severely diminished reactive oxygen intermediate synthesis, particularly if a matched sibling is available.

Alexandros Sfakianakis
Anapafseos 5 . Agios Nikolaos
Crete.Greece.72100
2841026182

6948891480

alsfakia@gmail.com