GIMAP5 deficiency reveals a mammalian ceramide-driven longevity assurance pathway.

Preserving cells in a functional, non-senescent state is a major goal for extending human healthspans. Model organisms reveal that longevity and senescence are genetically controlled, but how genes control longevity in different mammalian tissues is unknown. Here, we report a new human genetic disease that causes cell senescence, liver and immune dysfunction, and early mortality that results from deficiency of GIMAP5, an evolutionarily conserved GTPase selectively expressed in lymphocytes and endothelial cells. We show that GIMAP5 restricts the pathological accumulation of long-chain ceramides (CERs), thereby regulating longevity. GIMAP5 controls CER abundance by interacting with protein kinase CK2 (CK2), attenuating its ability to activate CER synthases. Inhibition of CK2 and CER synthase rescues GIMAP5-deficient T cells by preventing CER overaccumulation and cell deterioration. Thus, GIMAP5 controls longevity assurance pathways crucial for immune function and healthspan in mammals.

Therapeutic modalities and clinical outcomes in a large cohort with LRBA deficiency and CTLA4 insufficiency.

BACKGROUND: LPS-responsive beige-like anchor (LRBA) deficiency (LRBA-/-) and cytotoxic T-lymphocyte-associated antigen-4 (CTLA4) insufficiency (CTLA4+/-) are mechanistically overlapped diseases presenting with recurrent infections and autoimmunity. The effectiveness of different treatment regimens remains unknown. OBJECTIVE: Our aim was to determine the comparative efficacy and long-term outcome of therapy with immunosuppressants, CTLA4-immunoglobulin (abatacept), and hematopoietic stem cell transplantation (HSCT) in a single-country multicenter cohort of 98 patients with a 5-year median follow-up. METHODS: The 98 patients (63 LRBA-/- and 35 CTLA4+/-) were followed and evaluated at baseline and every 6 months for clinical manifestations and response to the respective therapies. RESULTS: The LRBA-/- patients exhibited a more severe disease course than did the CTLA4+/- patients, requiring more immunosuppressants, abatacept, and HSCT to control their symptoms. Among the 58 patients who received abatacept as either a primary or rescue therapy, sustained complete control was achieved in 46 (79.3%) without severe side effects. In contrast, most patients who received immunosuppressants as primary therapy (n = 61) showed either partial or no disease control (72.1%), necessitating additional immunosuppressants, abatacept, or transplantation. Patients with partial or no response to abatacept (n = 12) had longer disease activity before abatacept therapy, with higher organ involvement and poorer disease outcomes than those with a complete response. HSCT was performed in 14 LRBA-/- patients; 9 patients (64.2%) showed complete remission, and 3 (21.3%) continued to receive immunosuppressants after transplantation. HSCT and abatacept therapy gave rise to similar probabilities of survival. CONCLUSIONS: Abatacept is superior to immunosuppressants in controlling disease manifestations over the long term, especially when started early, and it may provide a safe and effective therapeutic alternative to transplantation.

Adverse COVID-19 outcomes in immune deficiencies: Inequality exists between subclasses.

BACKGROUND: Genetic deficiencies of immune system, referred to as inborn errors of immunity (IEI), serve as a valuable model to study human immune responses. In a multicenter prospective cohort, we evaluated the outcome of SARS-CoV-2 infection among IEI subjects and analyzed genetic and immune characteristics that determine adverse COVID-19 outcomes. METHODS: We studied 34 IEI patients (19M/15F, 12 [min: 0.6-max: 43] years) from six centers. We diagnosed COVID-19 infection by finding a positive SARS-CoV-2 PCR test (n = 25) and/or a lung tomography scoring (CORADS) ≥4 (n = 9). We recorded clinical and laboratory findings prospectively, fitted survival curves, and calculated fatality rates for the entire group and each IEI subclass. RESULTS: Nineteen patients had combined immune deficiency (CID), six with predominantly antibody deficiency (PAD), six immune dysregulation (ID), two innate immune defects, and one in the autoinflammatory class. Overall, 23.5% of cases died, with disproportionate fatality rates among different IEI categories. PAD group had a relatively favorable outcome at any age, but CIDs and IDs were particularly vulnerable. At admission, presence of dyspnea was an independent risk for COVID-related death (OR: 2.630, 95% CI; 1.198-5.776, p < .001). Concerning predictive roles of laboratory markers at admission, deceased subjects compared to survived had significantly higher CRP, procalcitonin, Troponin-T, ferritin, and total-lung-score (p = .020, p = .003, p = .014, p = .013, p = .020; respectively), and lower absolute lymphocyte count, albumin, and trough IgG (p = .012, p = .022, p = .011; respectively). CONCLUSION: Our data disclose a highly vulnerable IEI subgroup particularly disadvantaged for COVID-19 despite their youth. Future studies should address this vulnerability and consider giving priority to these subjects in SARS-Cov-2 therapy trials.

Recurrent angioedema in childhood: hereditary angioedema or histaminergic angioedema?

BACKGROUND: Recurrent angioedema is a rare entity during childhood. This study aimed to clarify differences between hereditary angioedema (HAE) and histaminergic angioedema (HA) in children. METHODS: Fifty-seven children with HAE (male 36.8%, 8.9 years [5.4-12.5]) and 42 children with recurrent HA (male 42.9%, 11.5 years [8.1-16.8]) were analyzed. RESULTS: The median age at symptom onset (6 [3-10]; 7.8 [4.5-13] years), frequency of angioedema episodes within last year (3 [2-5]; 5 [2-10]), and duration of symptoms (48 [24-48]; 24 [12-48] hours) were similar in the HAE and HA group, respectively. Recurrent urticaria was observed in 7.3% (n = 3) of patients in the HAE group and in 45.2% (n = 19) of the HA group (P < .001). While angioedema episodes involving the lips (n = 30; 71.4%; P = .035) and eyelids (n = 28; 66.7%; P = .012) were observed more frequently in the HA group, gastrointestinal involvement/abdominal pain (n = 15; 36.6%) was more common in HAE (P < .001). Itching as a prodromal symptom was detected in 47.6% (n = 20) of HA patients versus 14.6% (n = 6) of those with HAE (P = .002). In the logistic regression analysis for the diagnosis of HAE, a family history of angioedema (OR = 58.289 [95% CI 10.656-318.853], P < 001) and trauma (OR = 35.208 [95% CI [4.368-283.794]], P = .001) as a triggering factor were determined to be independent variables. CONCLUSION: A family history of angioedema, trauma as a triggering factor, and abdominal pain should suggest the diagnosis of HAE and the need for further investigation.

Clinical and immunological outcomes of SARS-CoV-2 infection in patients with inborn errors of immunity receiving different brands and doses of COVID-19 vaccines.

Introduction: Vaccines against severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) provide successful control of the coronavirus-2019 (COVID-19) pandemic. The safety and immunogenicity studies are encouraging in patients with inborn errors of immunity (IEI); however, data about mortality outcomes and severe disease after vaccination still need to be fully addressed. Therefore, we aimed to determine the clinical and immunological outcomes of SARS-CoV-2 infection in patients with IEI who have received vaccination. Materials and Methods: Eighty-eight patients with a broad range of molecular etiologies were studied; 45 experienced SARS-CoV-2 infection. Infection outcomes were analyzed in terms of genetic etiology, background clinical characteristics, and immunization history, including the type and number of doses received and the time elapsed since vaccination. In addition, anti-SARS-CoV-2 antibodies were quantified using electrochemiluminescent immunoassay. Results: Patients were immunized using one of the three regimens: inactivated (Sinovac, Coronavac®), mRNA (BNT162b2, Comirnaty®, Pfizer-Biontech), and a combination. All three regimens induced comparable anti-SARS-CoV-2 IgG levels, with no differences in the adverse events. Among 45 patients with COVID-19, 26 received a full course of vaccination, while 19 were vaccine-naive or received incomplete dosing. No patients died due to COVID-19 infection. The fully immunized group had a lower hospitalization rate (23% vs. 31.5%) and a shorter symptomatic phase than the others. Among the fully vaccinated patients, serum IgM and E levels were significantly lower in hospitalized patients than non-hospitalized patients. Conclusion: COVID-19 vaccines were well-tolerated by the IEI patients, and a full course of immunization was associated with lower hospitalization rates and a shorter duration of COVID-19 symptoms.

Clinical outcomes of hereditary angioedema on multiparous women.

OBJECTIVE: Significant concerns for patients with hereditary angioedema (HAE) include hormonal fluctuations and drug safety during pregnancy. The impact of the disease on childbearing in multiparous women remains to be elucidated. We aimed to investigate the clinical course and impacts of multiparity on HAE patients. STUDY DESIGN: This observational study included 15 multiparous women with HAE; a total of 88 pregnancies were assessed using a questionnaire and the patient's medical records. RESULTS: The median age was 36 (IQR, 33-39). Of 72 resulted in healthy babies without any congenital abnormalities. In sixteen pregnancies, 12 (13.6%) ended with spontaneous abortion; three resulted in stillbirth and one neonatal death. Two-thirds of the patients (n = 10) enounced a worsening in the frequency of angioedema attacks during pregnancy. There was no statistically significant difference compared with the nonpregnant period (p = 0.283). One-fifth of the patients (n = 3) reported alleviation in attacks. While most deliveries were vaginally (n = 57 babies), 19 deliveries in six patients were by cesarean section. None of the patients were aware of the diagnosis of HAE prior to their first pregnancies. After the diagnosis was made, eight patients received 263 vials of plasma-derived C1-inhibitor concentrate during a total of 13 pregnancies. No adverse events were reported. CONCLUSION: We conclude that our results on clinical course and outcomes of HAE in multiparous patients are consistent with the literature. A greater focus on multiparous HAE patients could produce exciting findings.

A Stk4-Foxp3-NF-κB p65 transcriptional complex promotes Treg cell activation and homeostasis.

The molecular programs involved in regulatory T (Treg) cell activation and homeostasis remain incompletely understood. Here, we show that T cell receptor (TCR) signaling in Treg cells induces the nuclear translocation of serine/threonine kinase 4 (Stk4), leading to the formation of an Stk4-NF-κB p65-Foxp3 complex that regulates Foxp3- and p65-dependent transcriptional programs. This complex was stabilized by Stk4-dependent phosphorylation of Foxp3 on serine-418. Stk4 deficiency in Treg cells, either alone or in combination with its homolog Stk3, precipitated a fatal autoimmune lymphoproliferative disease in mice characterized by decreased Treg cell p65 expression and nuclear translocation, impaired NF-κB p65-Foxp3 complex formation, and defective Treg cell activation. In an adoptive immunotherapy model, overexpression of p65 or the phosphomimetic Foxp3S418E in Stk3/4-deficient Treg cells ameliorated their immune regulatory defects. Our studies identify Stk4 as an essential TCR-responsive regulator of p65-Foxp3-dependent transcription that promotes Treg cell-mediated immune tolerance.