SCID and Other Inborn Errors of Immunity with Low TRECs - the Brazilian Experience.

Severe combined immunodeficiency, SCID, is a pediatric emergency that represents the most critical group of inborn errors of immunity (IEI). Affected infants present with early onset life-threatening infections due to absent or non-functional T cells. Without early diagnosis and curative treatment, most die in early infancy. As most affected infants appear healthy at birth, newborn screening (NBS) is essential to identify and treat patients before the onset of symptoms. Here, we report 47 Brazilian patients investigated between 2009 and 2020 for SCID due to either a positive family history and/or clinical impression and low TRECs. Based on clinical presentation, laboratory finding, and genetic information, 24 patients were diagnosed as typical SCID, 14 as leaky SCID, and 6 as Omenn syndrome; 2 patients had non-SCID IEI, and 1 remained undefined. Disease onset median age was 2 months, but at the time of diagnosis and treatment, median ages were 6.5 and 11.5 months, respectively, revealing considerable delay which affected negatively treatment success. While overall survival was 51.1%, only 66.7% (30/45) lived long enough to undergo hematopoietic stem-cell transplantation, which was successful in 70% of cases. Forty-three of 47 (91.5%) patients underwent genetic testing, with a 65.1% success rate. Even though our patients did not come from the NBS programs, the diagnosis of SCID improved in Brazil during the pilot programs, likely due to improved medical education. However, we estimate that at least 80% of SCID cases are still missed. NBS-SCID started to be universally implemented in the city of São Paulo in May 2021, and it is our hope that other cities will follow, leading to early diagnosis and higher survival of SCID patients in Brazil.

Tuberculosis and impaired IL-23-dependent IFN-γ immunity in humans homozygous for a common TYK2 missense variant.

Inherited IL-12Rß1 and TYK2 deficiencies impair both IL-12- and IL-23-dependent IFN-γ immunity and are rare monogenic causes of tuberculosis, each found in less than 1/600,000 individuals. We show that homozygosity for the common TYK2 P1104A allele, which is found in about 1/600 Europeans and between 1/1000 and 1/10,000 individuals in regions other than East Asia, is more frequent in a cohort of patients with tuberculosis from endemic areas than in ethnicity-adjusted controls (P = 8.37 × 10-8; odds ratio, 89.31; 95% CI, 14.7 to 1725). Moreover, the frequency of P1104A in Europeans has decreased, from about 9% to 4.2%, over the past 4000 years, consistent with purging of this variant by endemic tuberculosis. Surprisingly, we also show that TYK2 P1104A impairs cellular responses to IL-23, but not to IFN-α, IL-10, or even IL-12, which, like IL-23, induces IFN-γ via activation of TYK2 and JAK2. Moreover, TYK2 P1104A is properly docked on cytokine receptors and can be phosphorylated by the proximal JAK, but lacks catalytic activity. Last, we show that the catalytic activity of TYK2 is essential for IL-23, but not IL-12, responses in cells expressing wild-type JAK2. In contrast, the catalytic activity of JAK2 is redundant for both IL-12 and IL-23 responses, because the catalytically inactive P1057A JAK2, which is also docked and phosphorylated, rescues signaling in cells expressing wild-type TYK2. In conclusion, homozygosity for the catalytically inactive P1104A missense variant of TYK2 selectively disrupts the induction of IFN-γ by IL-23 and is a common monogenic etiology of tuberculosis.

The heterogeneity of autoimmune polyendocrine syndrome type 1: Clinical features, new mutations and cytokine autoantibodies in a Brazilian cohort from tertiary care centers.

Autoimmune polyendocrine syndrome type 1 (APS1) is characterized by multiorgan autoimmunity. We aim at characterizing a multi-center Brazilian cohort of APS1 patients by clinical evaluation, searching mutation in the AIRE gene, measuring serum autoantibodies, and investigating correlations between findings. We recruited patients based on the clinical criteria and tested them for AIRE mutations, antibodies against interferon type I and interleukins 17A, 17F and 22. We identified 12 unrelated families (13 patients) with typical signs of APS1 in the proband, and the screening of relatives recognized an asymptomatic child. Candidiasis was present in all cases, and 19 other manifestations were observed. All patients carried one of 10 different mutations in AIRE, being 3 new ones, and were positive for anti-interferon type I serum antibody. Anti-interleukin-17A levels inversely correlated with the number of manifestations in each patient. This negative correlation may suggest a protective effect of anti-interleukin-17A with a potential therapeutic application.

CD40 ligand deficiency causes functional defects of peripheral neutrophils that are improved by exogenous IFN-γ.

BACKGROUND: Patients with X-linked hyper-IgM syndrome caused by CD40 ligand (CD40L) deficiency often present with episodic, cyclic, or chronic neutropenia, suggesting abnormal neutrophil development in the absence of CD40L-CD40 interaction. However, even when not neutropenic and despite immunoglobulin replacement therapy, CD40L-deficient patients are susceptible to life-threatening infections caused by opportunistic pathogens, suggesting impaired phagocyte function and the need for novel therapeutic approaches. OBJECTIVES: We sought to analyze whether peripheral neutrophils from CD40L-deficient patients display functional defects and to explore the in vitro effects of recombinant human IFN-γ (rhIFN-γ) on neutrophil function. METHODS: We investigated the microbicidal activity, respiratory burst, and transcriptome profile of neutrophils from CD40L-deficient patients. In addition, we evaluated whether the lack of CD40L in mice also affects neutrophil function. RESULTS: Neutrophils from CD40L-deficient patients exhibited defective respiratory burst and microbicidal activity, which were improved in vitro by rhIFN-γ but not soluble CD40L. Moreover, neutrophils from patients showed reduced CD16 protein expression and a dysregulated transcriptome suggestive of impaired differentiation. Similar to CD40L-deficient patients, CD40L knockout mice were found to have impaired neutrophil responses. In parallel, we demonstrated that soluble CD40L induces the promyelocytic cell line HL-60 to proliferate and mature by regulating the expression of genes of the same Gene Ontology categories (eg, cell differentiation) when compared with those dysregulated in peripheral blood neutrophils from CD40L-deficient patients. CONCLUSION: Our data suggest a nonredundant role of CD40L-CD40 interaction in neutrophil development and function that could be improved in vitro by rhIFN-γ, indicating a potential novel therapeutic application for this cytokine.

II Brazilian Consensus on the use of human immunoglobulin in patients with primary immunodeficiencies.

In the last few years, new primary immunodeficiencies and genetic defects have been described. Recently, immunoglobulin products with improved compositions and for subcutaneous use have become available in Brazil. In order to guide physicians on the use of human immunoglobulin to treat primary immunodeficiencies, based on a narrative literature review and their professional experience, the members of the Primary Immunodeficiency Group of the Brazilian Society of Allergy and Immunology prepared an updated document of the 1st Brazilian Consensus, published in 2010. The document presents new knowledge about the indications and efficacy of immunoglobulin therapy in primary immunodeficiencies, relevant production-related aspects, mode of use (routes of administration, pharmacokinetics, doses and intervals), adverse events (major, prevention, treatment and reporting), patient monitoring, presentations available and how to have access to this therapeutic resource in Brazil.

RESUMO: Nos últimos anos, novas imunodeficiências primárias e defeitos genéticos têm sido descritos. Recentemente, produtos de imunoglobulina, com aprimoramento em sua composição e para uso por via subcutânea, tornaram-se disponíveis em nosso meio. Com o objetivo de orientar o médico no uso da imunoglobulina humana para o tratamento das imunodeficiências primárias, os membros do Grupo de Assessoria em Imunodeficiências da Associação Brasileira de Alergia e Imunologia produziram um documento que teve por base uma revisão narrativa da literatura e sua experiência profissional, atualizando o I Consenso Brasileiro publicado em 2010. Apresentam-se novos conhecimentos sobre indicações e eficácia do tratamento com imunoglobulina nas imunodeficiências primárias, aspectos relevantes sobre a produção, forma de utilização (vias de administração, farmacocinética, doses e intervalos), efeitos adversos (principais efeitos, prevenção, tratamento e notificação), monitorização do paciente, apresentações disponíveis e forma de obtenção deste recurso terapêutico em nosso meio.

II Brazilian Consensus on the use of human immunoglobulin in patients with primary immunodeficiencies / II Consenso Brasileiro sobre o uso de imunoglobulina humana em pacientes com imunodeficiências primárias

ABSTRACT In the last few years, new primary immunodeficiencies and genetic defects have been described. Recently, immunoglobulin products with improved compositions and for subcutaneous use have become available in Brazil. In order to guide physicians on the use of human immunoglobulin to treat primary immunodeficiencies, based on a narrative literature review and their professional experience, the members of the Primary Immunodeficiency Group of the Brazilian Society of Allergy and Immunology prepared an updated document of the 1st Brazilian Consensus, published in 2010. The document presents new knowledge about the indications and efficacy of immunoglobulin therapy in primary immunodeficiencies, relevant production-related aspects, mode of use (routes of administration, pharmacokinetics, doses and intervals), adverse events (major, prevention, treatment and reporting), patient monitoring, presentations available and how to have access to this therapeutic resource in Brazil.

RESUMO Nos últimos anos, novas imunodeficiências primárias e defeitos genéticos têm sido descritos. Recentemente, produtos de imunoglobulina, com aprimoramento em sua composição e para uso por via subcutânea, tornaram-se disponíveis em nosso meio. Com o objetivo de orientar o médico no uso da imunoglobulina humana para o tratamento das imunodeficiências primárias, os membros do Grupo de Assessoria em Imunodeficiências da Associação Brasileira de Alergia e Imunologia produziram um documento que teve por base uma revisão narrativa da literatura e sua experiência profissional, atualizando o I Consenso Brasileiro publicado em 2010. Apresentam-se novos conhecimentos sobre indicações e eficácia do tratamento com imunoglobulina nas imunodeficiências primárias, aspectos relevantes sobre a produção, forma de utilização (vias de administração, farmacocinética, doses e intervalos), efeitos adversos (principais efeitos, prevenção, tratamento e notificação), monitorização do paciente, apresentações disponíveis e forma de obtenção deste recurso terapêutico em nosso meio.

Human CD40 ligand deficiency dysregulates the macrophage transcriptome causing functional defects that are improved by exogenous IFN-γ.

BACKGROUND: CD40 ligand (CD40L) deficiency predisposes to opportunistic infections, including those caused by fungi and intracellular bacteria. Studies of CD40L-deficient patients reveal the critical role of CD40L-CD40 interaction for the function of T, B, and dendritic cells. However, the consequences of CD40L deficiency on macrophage function remain to be investigated. OBJECTIVES: We sought to determine the effect of CD40L absence on monocyte-derived macrophage responses. METHODS: After observing the improvement of refractory disseminated mycobacterial infection in a CD40L-deficient patient by recombinant human IFN-γ (rhIFN-γ) adjuvant therapy, we investigated macrophage functions from CD40L-deficient patients. We analyzed the killing activity, oxidative burst, cytokine production, and in vitro effects of rhIFN-γ and soluble CD40 ligand (sCD40L) treatment on macrophages. In addition, the effect of CD40L absence on the macrophage transcriptome before and after rhIFN-γ treatment was studied. RESULTS: Macrophages from CD40L-deficient patients exhibited defective fungicidal activity and reduced oxidative burst, both of which improved in the presence of rhIFN-γ but not sCD40L. In contrast, rhIFN-γ and sCD40L ameliorate impaired production of inflammatory cytokines. Furthermore, rhIFN-γ reversed defective control of Mycobacterium tuberculosis proliferation by patients' macrophages. The absence of CD40L dysregulated the macrophage transcriptome, which was improved by rhIFN-γ. Additionally, rhIFN-γ increased expression levels of pattern recognition receptors, such as Toll-like receptors 1 and 2, dectin 1, and dendritic cell-specific intercellular adhesion molecule 3-grabbing nonintegrin in macrophages from both control subjects and patients. CONCLUSION: Absence of CD40L impairs macrophage development and function. In addition, the improvement of macrophage immune responses by IFN-γ suggests this cytokine as a potential therapeutic option for patients with CD40L deficiency.

CLINICAL MANAGEMENT OF LOCALIZED BCG ADVERSE EVENTS IN CHILDREN.

BCG adverse events (BCG-AE) are rare conditions with no well-established treatment. This study aims to describe clinical characteristics and outcome of localized BCG-AE. Children with BCG-AEs who were treated at the Reference Center for Special Immunobiologicals of the Federal University of São Paulo from 2009 to 2011 were included. Patients were followed monthly until 3 months after healing. One hundred and twenty-seven patients with localized BCG-AE were followed: 67 (52.7%) had suppurative lymphadenitis; 30 (23.6%) injection-site abscess; five (3.9%) had enlarged lymph node > 3 cm; four (3.1%) had ulcer > 1 cm; and one (0.8%) had a local bacterial infection. Five patients (3.9%) had more than one BCG-AE simultaneously. Fifteen patients (11.8%) had atypical manifestations: seven wart-like lesions; five BCG reactivations; two other dermatologic lesions and one with vasomotor phenomenon. Isoniazid was used in 96 patients with typical BCG-AE (85.7%) until lesion resolution which took place 3.1 months later (in median); the healing rate was 90.6%. Patients with atypical manifestations had an individual approach. Regarding the outcome, 105/112 patients with typical AE and 13/15 patients with atypical AE had resolution of BCG-AE. Localized BCG-AE caused by BCG Moreau RJ had positive outcome when treated with a short course of isoniazid. Atypical BCG-AE are not infrequent.

Neonatal screening for severe combined immunodeficiency in Brazil / Triagem neonatal para imunodeficiência combinada grave no Brasil

Abstract Objective To apply, in Brazil, the T-cell receptor excision circles (TRECs) quantification technique using real-time polymerase chain reaction in newborn screening for severe combined immunodeficiency and assess the feasibility of implementing it on a large scale in Brazil. Methods 8715 newborn blood samples were collected on filter paper and, after DNA elution, TRECs were quantified by real-time polymerase chain reaction. The cutoff value to determine whether a sample was abnormal was determined by ROC curve analysis, using SSPS. Results The concentration of TRECs in 8,682 samples ranged from 2 to 2,181 TRECs/µL of blood, with mean and median of 324 and 259 TRECs/µL, respectively. Forty-nine (0.56%) samples were below the cutoff (30 TRECs/µL) and were reanalyzed. Four (0.05%) samples had abnormal results (between 16 and 29 TRECs/µL). Samples from patients previously identified as having severe combined immunodeficiency or DiGeorge syndrome were used to validate the assay and all of them showed TRECs below the cutoff. Preterm infants had lower levels of TRECs than full-term neonates. The ROC curve showed a cutoff of 26 TRECs/µL, with 100% sensitivity for detecting severe combined immunodeficiency. Using this value, retest and referral rates were 0.43% (37 samples) and 0.03% (3 samples), respectively. Conclusion The technique is reliable and can be applied on a large scale after the training of technical teams throughout Brazil.

Resumo Objetivo Aplicar no Brasil a técnica de quantificação de T-cell Receptor Excision Circles (TRECs) por PCR em tempo real para triagem neonatal de imunodeficiência combinada grave (SCID) e avaliar se é possível fazê-la em grande escala em nosso país. Métodos Foram coletadas em papel filtro 8.715 amostras de sangue de recém-nascidos e, após eluição do DNA, os TRECs foram quantificados por PCR em tempo real. O valor de corte para determinar se uma amostra é anormal foi determinado pela análise de curva ROC com o programa SSPS. Resultados A concentração de TRECs em 8.682 amostras analisadas variou entre 2 e 2.181 TRECs/µL de sangue, com média e mediana de 324 e 259 TRECs/µL, respectivamente. Das amostras, 49 (0,56%) ficaram abaixo do valor de corte (30 TRECs/µL) e foram requantificadas. Quatro (0,05%) mantiveram resultados anormais (entre 16 e 29 TRECs/µL). Amostras de pacientes com diagnóstico clínico prévio de SCID e síndrome de DiGeorge foram usadas para validar o ensaio e todas apresentaram concentração de TRECs abaixo do valor de corte. Recém-nascidos prematuros apresentaram menores níveis de TRECs comparados com os nascidos a termo. Com o uso da curva ROC em nossos dados, chegamos ao valor de corte de 26 TRECs/µL, com sensibilidade de 100% para detecção de SCID. Com o uso desse valor, as taxas de repetição e encaminhamento ficaram em 0,43% (37 amostras) e 0,03% (3 amostras), respectivamente. Conclusão A técnica é factível e pode ser implantada em grande escala, após treinamento técnico das equipes envolvidas.

Interferon-gamma reduces the proliferation of M. tuberculosis within macrophages from a patient with a novel hypomorphic NEMO mutation.

X-linked ectodermal dysplasia with immunodeficiency (XL-EDA-ID) is caused by mutations in the nuclear factor-kappa B essential modulator (NEMO) gene. Here, we report the clinical and genetic features of a XL-EDA-ID patient who developed bacillus Calmette-Guérin infection. Patient lymphocytes failed to degrade IκB-α, and sequencing of NEMO identified the novel mutation c.1238A>C/p.H413P. Furthermore, patient monocyte-derived macrophages ingested Mycobacterium tuberculosis normally, but failed to control the intracellular proliferation of bacilli, a defect which was improved in the presence of interferon-gamma (IFN-γ). This work expands the genetic spectrum of XL-EDA-ID and demonstrates improvement in macrophage function in a NEMO-deficient patient by IFN-γ.

Neonatal screening for severe combined immunodeficiency in Brazil.

OBJECTIVE: To apply, in Brazil, the T-cell receptor excision circles (TRECs) quantification technique using real-time polymerase chain reaction in newborn screening for severe combined immunodeficiency and assess the feasibility of implementing it on a large scale in Brazil. METHODS: 8715 newborn blood samples were collected on filter paper and, after DNA elution, TRECs were quantified by real-time polymerase chain reaction. The cutoff value to determine whether a sample was abnormal was determined by ROC curve analysis, using SSPS. RESULTS: The concentration of TRECs in 8,682 samples ranged from 2 to 2,181TRECs/µL of blood, with mean and median of 324 and 259TRECs/µL, respectively. Forty-nine (0.56%) samples were below the cutoff (30TRECs/µL) and were reanalyzed. Four (0.05%) samples had abnormal results (between 16 and 29TRECs/µL). Samples from patients previously identified as having severe combined immunodeficiency or DiGeorge syndrome were used to validate the assay and all of them showed TRECs below the cutoff. Preterm infants had lower levels of TRECs than full-term neonates. The ROC curve showed a cutoff of 26TRECs/µL, with 100% sensitivity for detecting severe combined immunodeficiency. Using this value, retest and referral rates were 0.43% (37 samples) and 0.03% (3 samples), respectively. CONCLUSION: The technique is reliable and can be applied on a large scale after the training of technical teams throughout Brazil.

Health-Related Quality of Life and Health Resource Utilization in Patients with Primary Immunodeficiency Disease Prior to and Following 12 Months of Immunoglobulin G Treatment.

PURPOSE: Health-related quality of life (HRQOL) has not been examined in patients with predominant antibody deficiency both pre- and post-immunoglobulin G (IgG) treatment initiation. HRQOL and health resource utilization (HRU) were assessed in newly diagnosed patients with primary immunodeficiency disease (PIDD) pre- and 12 months post-IgG treatment initiation. METHODS: Adults (age ≥18 years) completed the 36-item Short Form Health Survey, version 2; pediatric patients (PP)/caregivers completed the Pediatric Quality of Life Inventory (PedsQL). Scores were compared with normative data from the US general population (GP) and patients with other chronic conditions (OCC). RESULTS: Seventeen adult patients (APs), 8 PPs, and 8 caregivers completed baseline assessments. APs had significantly lower baseline mean physical component summary scores versus GP (37.4 vs 50.5, p < 0.01) adults with chronic back pain (44.1, p < 0.05) or cancer (44.4, p < 0.05) and lower mental component summary scores versus GP (41.6 vs 49.2, p < 0.05). PPs had lower PedsQL total (63.1 vs 82.7), physical summary (64.5 vs 84.5), and psychosocial summary (62.5 vs 81.7) scores versus GP. Post-IgG treatment, 14 APs, 6 PPs, and 8 caregivers completed assessments. Hospital admissions (0.2 versus 1.8, p < 0.01), serious infections (3.3 versus 10.9, p < 0.01) and antibiotic prescriptions (3.0 versus 7.1; p < 0.01) decreased significantly overall. While APs reported significant improvement in role-physical (p = 0.01), general health (p < 0.01), and social functioning (p = 0.02) and caregivers in vitality (p < 0.01), PPs did not. CONCLUSIONS: Pre-IgG treatment, patients with PIDD experienced diminished HRQOL versus GP and patients with OCC; post-treatment, HRU decreased and certain HRQOL aspects improved for APs and caregivers.

PROTECTIVE LEVELS OF VARICELLA-ZOSTER ANTIBODY DID NOT EFFECTIVELY PREVENT CHICKENPOX IN AN X-LINKED AGAMMAGLOBULINEMIA PATIENT.

We describe the case of an eight-year-old boy with X-linked agammaglobulinemia who developed mild varicella despite regular intravenous immunoglobulin (IVIG) therapy. He maintained protective antibody levels against varicella and the previous batches of IVIG that he received had adequate varicella-specific IgG levels. The case illustrates that IVIG may not prevent VZV infection.

Neutrophil oxidative burst activates ATM to regulate cytokine production and apoptosis.

Neutrophils play an essential role in the initial stages of inflammation by balancing pro- and antiinflammatory signals. Among these signals are the production of proinflammatory cytokines and the timely initiation of antiinflammatory cell death via constitutive apoptosis. Here we identify ataxia-telangiectasia mutated (ATM) kinase as a modulator of these neutrophil functions. Ataxia-telangiectasia (AT) is a pleiotropic multisystem disorder caused by mutations in the gene-encoding ATM, a master regulator of the DNA damage response. In addition to progressive neurodegeneration and high rates of cancer, AT patients have numerous symptoms that can be linked to chronic inflammation. We report that neutrophils isolated from patients with AT overproduce proinflammatory cytokines and have a prolonged lifespan compared with healthy controls. This effect is partly mediated by increases in activation of p38 MAP kinase. Furthermore, we show that the oxidative burst, catalyzed by nicotinamide adenine dinucleotide phosphate oxidase, can activate ATM in neutrophils. Finally, activation of ATM and DNA damage signaling suppress cytokine production and can abrogate the overproduction of IL-8 in ROS-deficient cells. This reveals a novel mechanism for the regulation of cytokine production and apoptosis, establishing DNA damage as a downstream mediator of immune regulation by reactive oxygen species. We propose that deficiencies in the DNA damage response, like deficiencies in the oxidative burst seen in chronic granulomatous disease, could lead to pathologic inflammation.

PROTECTIVE LEVELS OF VARICELLA-ZOSTER ANTIBODY DID NOT EFFECTIVELY PREVENT CHICKENPOX IN AN X-LINKED AGAMMAGLOBULINEMIA PATIENT / Nível sérico adequado de anticorpo contra o vírus da varicela-zoster não foi suficiente para prevenir a infecção em criança com agamaglobulinemia ligada ao X

SUMMARY We describe the case of an eight-year-old boy with X-linked agammaglobulinemia who developed mild varicella despite regular intravenous immunoglobulin (IVIG) therapy. He maintained protective antibody levels against varicella and the previous batches of IVIG that he received had adequate varicella-specific IgG levels. The case illustrates that IVIG may not prevent VZV infection.

RESUMO Relatamos o caso de uma criança com agamaglobulinemia ligada ao X, sexo masculino, oito anos de idade, que desenvolveu quadro de varicela leve, apesar do tratamento regular com imunoglobulina intravenosa (IVIG). O paciente mantinha níveis adequados de imunoglobulina (IgG) contra varicela, assim como, os últimos lotes de IVIG por ele recebido também apresentavam níveis adequados do anticorpo específico. O caso ilustra que o tratamento regular com IVIG não é suficiente para prevenir a infecção pelo vírus da varicela-zoster.