Anti-Interleukin-23 Autoantibodies in Adult-Onset Immunodeficiency.

BACKGROUND: Autoantibodies against interleukin-12 (anti-interleukin-12) are often identified in patients with thymoma, but opportunistic infections develop in only some of these patients. Interleukin-12 (with subunits p40 and p35) shares a common subunit with interleukin-23 (subunits p40 and p19). In a patient with disseminated Burkholderia gladioli infection, the identification of both anti-interleukin-23 and anti-interleukin-12 prompted further investigation. METHODS: Among the patients (most of whom had thymoma) who were known to have anti-interleukin-12, we screened for autoantibodies against interleukin-23 (anti-interleukin-23). To validate the potential role of anti-interleukin-23 with respect to opportunistic infection, we tested a second cohort of patients with thymoma as well as patients without either thymoma or known anti-interleukin-12 who had unusual infections. RESULTS: Among 30 patients with anti-interleukin-12 who had severe mycobacterial, bacterial, or fungal infections, 15 (50%) also had autoantibodies that neutralized interleukin-23. The potency of such neutralization was correlated with the severity of these infections. The neutralizing activity of anti-interleukin-12 alone was not associated with infection. In the validation cohort of 91 patients with thymoma, the presence of anti-interleukin-23 was associated with infection status in 74 patients (81%). Overall, neutralizing anti-interleukin-23 was detected in 30 of 116 patients (26%) with thymoma and in 30 of 36 patients (83%) with disseminated, cerebral, or pulmonary infections. Anti-interleukin-23 was present in 6 of 32 patients (19%) with severe intracellular infections and in 2 of 16 patients (12%) with unusual intracranial infections, including Cladophialophora bantiana and Mycobacterium avium complex. CONCLUSIONS: Among patients with a variety of mycobacterial, bacterial, or fungal infections, the presence of neutralizing anti-interleukin-23 was associated with severe, persistent opportunistic infections. (Funded by the National Institute of Allergy and Infectious Diseases and others.).

Who's your data? Primary immune deficiency differential diagnosis prediction via machine learning and data mining of the USIDNET registry.

PURPOSE: There are currently more than 480 primary immune deficiency (PID) diseases and about 7000 rare diseases that together afflict around 1 in every 17 humans. Computational aids based on data mining and machine learning might facilitate the diagnostic task by extracting rules from large datasets and making predictions when faced with new problem cases. In a proof-of-concept data mining study, we aimed to predict PID diagnoses using a supervised machine learning algorithm based on classification tree boosting. METHODS: Through a data query at the USIDNET registry we obtained a database of 2396 patients with common diagnoses of PID, including their clinical and laboratory features. We kept 286 features and all 12 diagnoses to include in the model. We used the XGBoost package with parallel tree boosting for the supervised classification model, and SHAP for variable importance interpretation, on Python v3.7. The patient database was split into training and testing subsets, and after boosting through gradient descent, the predictive model provides measures of diagnostic prediction accuracy and individual feature importance. After a baseline performance test, we used the Class Weighting Hyperparameter, or scale_pos_weight to correct for imbalanced classification. RESULTS: The twelve PID diagnoses were CVID (1098 patients), DiGeorge syndrome, Chronic granulomatous disease, Congenital agammaglobulinemia, PID not otherwise classified, Specific antibody deficiency, Complement deficiency, Hyper-IgM, Leukocyte adhesion deficiency, ectodermal dysplasia with immune deficiency, Severe combined immune deficiency, and Wiskott-Aldrich syndrome. For CVID, the model found an accuracy on the train sample of 0.80, with an area under the ROC curve (AUC) of 0.80, and a Gini coefficient of 0.60. In the test subset, accuracy was 0.76, AUC 0.75, and Gini 0.51. The positive feature value to predict CVID was highest for upper respiratory infections, asthma, autoimmunity and hypogammaglobulinemia. Features with the highest negative predictive value were high IgE, growth delay, abscess, lymphopenia, and congenital heart disease. For the rest of the diagnoses, accuracy stayed between 0.75 and 0.99, AUC 0.46-0.87, Gini 0.07-0.75, and LogLoss 0.09-8.55. DISCUSSION: Clinicians should remember to consider the negative predictive features together with the positives. We are calling this a proof-of-concept study to continue with our explorations. A good performance is encouraging, and feature importance might aid feature selection for future endeavors. In the meantime, we can learn from the rules derived by the model and build a user-friendly decision tree to generate differential diagnoses.

[Early detection of WHIM symdrome. A case report]. / Identificación temprana de síndrome de WHIM. Informe de un caso.

BACKGROUND: WHIM syndrome corresponds to an inborn error of innate and intrinsic immunity, characterized by: warts (Warts), Hypogammaglobulinemia, Infections and Myelocathexis, for its acronym in English. CASE REPORT: 4-year-old male, with severe neutropenia and B-cell lymphopenia from birth, without severe infections or warts; the panel genetic sequencing study of primary immunodeficiencies with the CXCR4 c.1000C>T (p.Arg334*) variant, which is associated with WHIM syndrome. CONCLUSIONS: The diagnosis of severe neutropenia from birth should include the search for inborn errors of immunity, through genetic sequencing studies, especially in asymptomatic or oligosymptomatic patients.

ANTECEDENTES: El síndrome WHIM corresponde a un error innato de la inmunidad innata e intrínseca, caracterizada por verrugas (Warts), hipogammaglobulinemia, infecciones y mielocatexis, por sus siglas en inglés. REPORTE DE CASO: Paciente masculino de 4 años, con neutropenia severa y linfopenia de células B desde el nacimiento, sin infecciones severas ni verrugas. El estudio de secuenciación genética informó la variante CXCR4 c.1000C>T (p.Arg334*), relacionada con el síndrome de WHIM. CONCLUSIÓN: El diagnóstico de neutropenia severa desde el nacimiento debe incluir la búsqueda de errores innatos de la inmunidad, mediante estudios de secuenciación genética, especialmente en pacientes asintomáticos u oligosintomáticos.

Efficacy and Safety of Interferon-Gamma in Chronic Granulomatous Disease: a Systematic Review and Meta-analysis.

BACKGROUND: Chronic granulomatous disease (CGD) is a primary immunodeficiency with increased susceptibility to several bacteria, fungi, and mycobacteria, caused by defective or null superoxide production by the NADPH oxidase enzymatic complex. Accepted treatment consists mainly of antimicrobial prophylaxis. The role of human recombinant subcutaneous interferon-gamma (IFNγ) is less clear since the available evidence on its efficacy derives mainly from a single clinical trial that has been challenged. OBJECTIVE: We aimed to assess the efficacy and safety of IFNγ as an added treatment for CGD when compared to antimicrobial prophylaxis alone. METHODS: A literature search was conducted using MeSH terms "Chronic granulomatous disease" AND ("interferon gamma" OR "interferon-gamma"), as well as antibiotics, placebo, no therapy, clinical trial, and trial, on MEDLINE, EMBASE, LILACS, WHOs, CENTRAL, KOREAMED, The Cochrane Library, clinicaltrials.gov, and abstracts from meetings, from 1976 to July 2022. We included clinical trials (CT) and prospective follow-up studies and registered the number of serious infections (requiring hospitalization and IV antibiotics) and deaths, adverse events, and autoimmune complications, in patients treated for CGD with antimicrobial prophylaxis plus IFN-γ, versus antimicrobial prophylaxis alone. We assessed the quality of the studies using risk of bias and STROBE. We performed a meta-analysis by calculating both Peto's odds ratio (OR) and risk reduction (RR) through the Mantel-Haenszel method with a fixed-effect model, using Review Manager 5.4, and we reported the number needed to treat (NNT). RESULTS: We identified 54 matches from databases and 4 from other sources. We excluded 12 duplicates, 7 titles, and 9 abstracts for relevance, after which we had 30 eligible studies. Twenty-four were then excluded after reading the full text. Six papers were included: one randomized CT and 5 follow-up studies. In total, 324 patients with Chronic granulomatous disease were followed for 319 months under treatment with antibiotic prophylaxis plus interferon-gamma or placebo (or antibiotic prophylaxis alone), reported between the years 1991 and 2016. Three of the studies included a control group, allowing for the aggregate analysis of efficacy (prevention of serious infections). The aggregate OR was 0.49, with a 95% confidence interval of 0.19 to 1.23. The risk ratio for serious infection was 0.56 (95%CI 0.35-0.90) under IFN-γ. The meta-analysis thus favors interferon-gamma for a risk reduction of serious infection. DISCUSSION: The results from this meta-analysis support the use of IFN-γ in the treatment of patients with CGD. However, we found insufficient clinical evidence and believe more clinical trials are needed to better assess the efficacy and long-term safety of IFN-γ.

Activating de novo monoallelic variants causing inborn errors of immunity in two unrelated children born of HIV-seroconcordant couples.

INTRODUCTION: Around 20% of all inborn errors of immunity (IEI) are autosomal dominant or monoallelic, either by haploinsufficiency, negative dominance, or gain of function (GOF). GOF phenotypes usually include autoinflammation, autoimmunity, lymphoproliferation, allergies, and some infections. CASE SERIES: We describe the cases of two unrelated patients born of HIV-seroconcordant parents. Both patients are HIV-negative but carry de novo GOF missense variants that resulted in inflammatory lymphoproliferative IEI diseases: signal transducer and activator of transcription 3 (STAT3)-GOF and phosphatidylinositol 3-kinase, catalytic delta (PIK3CD)-GOF. Both variants were found through whole-exome sequencing and confirmed by Sanger.An 11-year-old male with recurrent sinopulmonary infections, dysmorphism, growth delay, bronchiectasis, and mild mental retardation, as well as lymphopenia, thrombocytopenia, and high immunoglobulin M. Both his parents were known to be HIV-positive under anti-retroviral treatment. HIV infection was repeatedly ruled out in the patient, whom through whole-exome sequencing was found to have a heterozygous missense variant in exon 24 of PIK3CD, a hotspot transition, and the most reported variant in PIK3CD-GOF patients.A 6-year-old male with autoimmune hemolytic anemia, lymphoproliferation, short stature, and intractable diarrhea. Both his parents were found to be HIV-positive. HIV was repeatedly ruled out in the patient by ELISA and viral load. He was found to have a heterozygous missense/splice variant in exon 22 of STAT3, a hotspot transition, and the most reported variant in STAT3-GOF patients. DISCUSSION: The AID/APOBEC3 A-H family of proteins are cytidine deaminases that induce G>A hypermutation in both the invading viral DNA and the host genome, which results in stop codons inside the endogenized retroviral sequence. Both variants found in our patients are G to A transitions. Retroviral infection might thus have resulted in host genome instability, and our patients' rare congenital diseases are the unfortunate consequence of somatic hypermutation in one of their parents' gametes.

Not enough by half: NFAT5 haploinsufficiency in two patients with Epstein-Barr virus susceptibility.

Introduction: The transcription factor Nuclear factor of activated T cells 5 (NFAT5), pivotal in immune regulation and function, can be induced by osmotic stress and tonicity-independent signals. Objective: We aimed to investigate and characterize two unrelated patients with Epstein-Barr virus susceptibility and no known genetic etiology. Methods: After informed consent, we reviewed the electronic charts, extracted genomic DNA, performed whole-exome sequencing, filtered, and prioritized their variants, and confirmed through Sanger sequencing, family segregation analysis, and some functional assays, including lymphoproliferation, cytotoxicity, and characterization of natural killer cells. Results: We describe two cases of pediatric Mexican patients with rare heterozygous missense variants in NFAT5 and EBV susceptibility, a school-age girl with chronic-active infection of the liver and bowel, and a teenage boy who died of hemophagocytic lymphohistiocytosis. Discussion: NFAT5 is an important regulator of the immune response. NFAT5 haploinsufficiency has been described as an immunodeficiency syndrome affecting both innate and adaptive immunity. EBV susceptibility might be another manifestation in the spectrum of this disease.

Immunodeficiency, autoimmunity, and increased risk of B cell malignancy in humans with TRAF3 mutations.

Tumor necrosis factor receptor-associated factor 3 (TRAF3) is a central regulator of immunity. TRAF3 is often somatically mutated in B cell malignancies, but its role in human immunity is not defined. Here, in five unrelated families, we describe an immune dysregulation syndrome of recurrent bacterial infections, autoimmunity, systemic inflammation, B cell lymphoproliferation, and hypergammaglobulinemia. Affected individuals each had monoallelic mutations in TRAF3 that reduced TRAF3 expression. Immunophenotyping showed that patients' B cells were dysregulated, exhibiting increased nuclear factor-κB 2 activation, elevated mitochondrial respiration, and heightened inflammatory responses. Patients had mild CD4+ T cell lymphopenia, with a reduced proportion of naïve T cells but increased regulatory T cells and circulating T follicular helper cells. Guided by this clinical phenotype, targeted analyses demonstrated that common genetic variants, which also reduce TRAF3 expression, are associated with an increased risk of B cell malignancies, systemic lupus erythematosus, higher immunoglobulin levels, and bacterial infections in the wider population. Reduced TRAF3 conveys disease risks by driving B cell hyperactivity via intrinsic activation of multiple intracellular proinflammatory pathways and increased mitochondrial respiration, with a likely contribution from dysregulated T cell help. Thus, we define monogenic TRAF3 haploinsufficiency syndrome and demonstrate how common TRAF3 variants affect a range of human diseases.

Stem-cell transplantation for children with primary immune deficiencies: A retrospective study of 19 patients from one centre in Mexico.

INTRODUCTION: For many patients with primary immune deficiency (PID), stem-cell transplantation (SCT) may be life-saving. OBJECTIVE: To review our experience of 11 years transplanting children with PID in Mexico. METHODS: Chart review of patients who underwent SCT from 2008 to 2018, to describe their diagnoses, time to transplant, conditioning regime, survival rate and outcomes. All patients received post-transplant cyclophosphamide as graft-versus-host-disease (GVHD) prophylaxis. RESULTS: 19 patients with combined, phagocytic or syndromic PID from 5 states. Twelve of them were male (58%) and 14 survive (79%). Mean age at HSCT was 41.9 months; mean time from diagnosis was 31.2 months. Seven grafts were umbilical cord and 12 haploidentical. The conditioning regime was myeloablative, with five primary graft failures. Two patients had partial and 10 full chimerism. Five patients died within 2 months after transplant. Immune reconstitution was complete in 11 of 19 patients. We found a prevalence of 21% GVHD. DISCUSSION: We describe 19 patients from Mexico with 8 PID diagnoses who underwent allogenic HSCT over a period of 11 years. Survival rate and other outcomes compare well with industrialized countries. We recommend the use of post-transplant cyclophosphamide to prevent GVHD in scenarios of resource scarcity and a lack of HLA-identical donors.

Severe congenital neutropenia due to G6PC3 deficiency: Case series of five patients and literature review.

BACKGROUND AND OBJECTIVES: Glucose-6-phosphate catalytic subunit 3 (G6PC3) deficiency is characterized by severe congenital neutropenia with recurrent pyogenic infections, a prominent superficial venous pattern and cardiovascular and urogenital malformations caused by an alteration of glucose homeostasis, with increased endoplasmic reticulum stress and cell apoptosis. METHODS: We reviewed our patients with G6PC3 deficiency diagnosed along the last decade in Mexico; we also searched the PubMed/Medline database for the terms ('G6PC3 deficiency' OR 'Dursun syndrome' OR 'Severe congenital neutropenia type 4'), and selected articles published in English from 2009 to 2020. RESULTS: We found 89 patients reported from at least 14 countries in 4 continents. We describe five new cases from Mexico. Of the 94 patients, 56% are male, 48% from Middle East countries and none of them had adverse reactions to live vaccines; all presented with at least 1 severe infection prior to age 2. Seventy-five per cent had syndromic features, mainly atrial septal defect in 55% and prominent superficial veins in 62%. CONCLUSIONS: With a total of 94 patients reported in the past decade, we delineate the most frequent laboratory and genetic features, their treatment and outcomes, and to expand the knowledge of syndromic and non-syndromic phenotypes in these patients.

Case Report: DOCK8 Deficiency Without Hyper-IgE in a Child With a Large Deletion.

Autosomal recessive (AR) DOCK8 deficiency is a well-known actinopathy, a combined primary immune deficiency with impaired actin polymerization that results in altered cell mobility and immune synapse. DOCK8-deficient patients present early in life with eczema, viral cutaneous infections, chronic mucocutaneous candidiasis, bacterial pneumonia, and abscesses, together with eosinophilia, thrombocytosis, lymphopenia, and variable dysgammaglobulinemia that usually includes Hyper-IgE. In fact, before its genetic etiology was known, patients were described as having a form of Hyper-IgE syndrome, a name now deprecated in favor of genetic defects. We describe a school-age male patient with a clinical picture suggestive of DOCK8 deficiency, except for high serum IgE or a family history: early onset, failure to thrive, eczema, warts, condyloma, bronchiolitis, pneumonia, recurrent otitis media, bronchiectasis, candidiasis, leukocytosis, eosinophilia, high IgA, low IgG, and low CD4+ T cells. We were able to confirm the diagnosis through protein expression and whole-exome sequencing. We review the clinical, laboratory, and genetic features of 200 DOCK8-deficient patients; at least 4 other patients have had no elevated IgE, and about 40% do not have Hyper-IgE (above 1,000 IU/mL). Despite this, the constellation of signs, symptoms, and findings allow the suspicion of DOCK8 deficiency and other actinopathies.

COVID-19 in the Context of Inborn Errors of Immunity: a Case Series of 31 Patients from Mexico.

INTRODUCTION: Patients with inborn errors of immunity (IEI) have a compromised or inappropriate immune response. Although they might be considered a high-risk group for severe SARS-CoV-2 infection, the reported impact of COVID-19 in these patients has been reassuring, while the differential susceptibility of distinct types of IEI remains unclear. OBJECTIVE: We aimed to describe the findings and outcomes of our known patients with IEI who were diagnosed with COVID-19. METHODS: In a retrospective study from March 2020 to February 2021, four centers in Mexico collected clinical, laboratory, and genetic data from pediatric and adult patients with known diagnoses of IEI who presented with COVID-19, based on compatible symptoms and positive SARS-CoV-2 testing or known household exposure. RESULTS: We report 31 patients with known IEI from Mexico who presented with SARS-CoV-2 infection. Seventy-four percent were male, 52% were pediatric, and 81% survived. Their ages ranged from 5 months to 56 years, with a median of 17 years. Sixty-five percent had predominant antibody deficiencies, 48% were hospitalized, and 26% required ICU. Pediatric patients had a higher hospital admission rate than adults. Inpatient mortality was 40%, and ICU mortality rate was 63%. Forty-eight percent developed pneumonia, while 36% had evidence of hyperinflammation (4 adults and 7 children). Predominant laboratory features were lymphopenia and thrombocytopenia, seen in 70 and 44% of patients, respectively. The serum D-dimer median value was 2.6 (0.5-20.6) µg/mL, and the median highest ferritin value was 1015 (32-10,303) ng/mL. Intravenous immunoglobulin was used in 80% of patients. Other treatments included macrolides (39%) and corticosteroids (29%). Six patients died from secondary infection or uncontrolled systemic inflammation. DISCUSSION: Although impaired immunity due to IEI may be a predisposing factor for severe COVID-19, most of our patients with IEI who acquired the SARS-CoV-2 infection developed a well-tolerated infection and survived, as have more than 80% of worldwide reported patients to date. An impaired immune or inflammatory response may be a predisposing factor for some and a protective factor for others. A systematic review of the literature could help identify those patients at risk of severe disease and complications. Healthcare-associated infections should be aggressively prevented.

Diagnostic and therapeutic caveats in Griscelli syndrome.

Griscelli syndrome (GS) is a rare autosomal recessive disease with characteristic pigment distribution, and there are currently 3 types according to the underlying genetic defect and clinical features. We present the case of a girl born from consanguineous parents who presented with predominant neurologic symptoms, silvery hair and granulomatous skin lesions. Cerebral magnetic resonance revealed diffuse white matter lesions, and central nervous system (CNS) lymphocytic infiltration was suspected. The patient underwent haematopoietic stem cell transplantation with graft failure and autologous reconstitution. She developed elevated liver enzyme with a cholestatic pattern. Multiple liver biopsies revealed centrilobular cholestasis and unspecific portal inflammation that improved with immunomodulatory treatment. She was revealed to have an impaired cytotoxicity in NK cells and a decreased expression of RAB27A. However, no variants were found in the gene. All types of GS present with pigment dilution and irregular pigment clumps that can be seen through light microscopy in hair and skin biopsy. Dermic granulomas and immunodeficiency with infectious and HLH predisposition have been described in GS type 2 (GS2). Neurologic alterations might be seen in GS type 1 (GS1) and GS type 2 (GS2), due to different mechanisms. GS1 presents with neurologic impairment secondary to myosin Va role in neuronal development and synapsis. Meanwhile, GS2 can present with neurologic impairment secondary to SNC HLH. Clinical features and cytotoxicity might aid in differentiating GS1 and GS2, especially since treatment differs.

Genetic, Immunological, and Clinical Features of the First Mexican Cohort of Patients with Chronic Granulomatous Disease.

PURPOSE: Chronic granulomatous disease (CGD) is a primary immunodeficiency characterized by an inability of phagocytes to produce reactive oxygen species, impairing their killing of various bacteria and fungi. We summarize here the 93 cases of CGD diagnosed in Mexico from 2011 to 2019. METHODS: Thirteen Mexican hospitals participated in this study. We describe the genetic, immunological, and clinical features of the 93 CGD patients from 78 unrelated kindreds. RESULTS: Eighty-two of the patients (88%) were male. All patients developed bacterial infections and 30% suffered from some kind of fungal infection. Fifty-four BCG-vaccinated patients (58%) presented infectious complications of BCG vaccine. Tuberculosis occurred in 29%. Granulomas were found in 56% of the patients. Autoimmune and inflammatory diseases were present in 15% of patients. A biological diagnosis of CGD was made in 89/93 patients, on the basis of NBT assay (n = 6), DHR (n = 27), and NBT plus DHR (n = 56). The deficiency was complete in all patients. The median age of biological diagnosis was 17 months (range, 0-186 months). A genetic diagnosis was made in 83/93 patients (when material was available), corresponding to CYBB (n = 64), NCF1 (n = 7), NCF2 (n = 7), and CYBA (n = 5) mutations. CONCLUSIONS: The clinical manifestations in these Mexican CGD patients were similar to those in patients elsewhere. This cohort is the largest in Latin America. Mycobacterial infections are an important cause of morbidity in Mexico, as in other countries in which tuberculosis is endemic and infants are vaccinated with BCG. X-linked CGD accounted for most of the cases in Mexico, as in other Latin American countries. However, a significant number of CYBA and NCF2 mutations were identified, expanding the spectrum of known causal mutations.

Antimicrobial peptides: general overview and clinical implications in human health and disease.

Antimicrobial peptides (AMPs) are evolutionarily conserved molecules involved in the defense mechanisms of a wide range of organisms. Produced in bacteria, insects, plants and vertebrates, AMPs protect against a broad array of infectious agents. In mammals these peptides protect against bacteria, viruses, fungi, and certain parasites. Recently, novel biologic effects of AMPs have been documented such as endotoxin neutralization, chemotactic and immunomodulating activities, induction of angiogenesis and wound repair. Thus these ancestral molecules are crucial components of the innate immune system and attractive candidates for novel therapeutic approaches. This review focuses on cathelicin and defensins, the most documented human AMPs, and discusses their antimicrobial activity and pleiotropic immunomodulating effects on inflammatory and infectious diseases.