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Editorial: Screening for Primary Immunodeficiency Disorders (PIDDs) in Neonates.

January 12, 2021 By Manish Butte

Editorial: Screening for Primary Immunodeficiency Disorders (PIDDs) in Neonates.

Front Immunol. 2020;11:633266

Authors: Hossny E, Condino-Neto A, Hammarström L, Walter JE

PMID: 33424872 [PubMed – in process]

HCoV- and SARS-CoV-2 Cross-Reactive T Cells in CVID Patients.

January 12, 2021 By Manish Butte

HCoV- and SARS-CoV-2 Cross-Reactive T Cells in CVID Patients.

Front Immunol. 2020;11:607918

Authors: Steiner S, Sotzny F, Bauer S, Na IK, Schmueck-Henneresse M, Corman VM, Schwarz T, Drosten C, Wendering DJ, Behrends U, Volk HD, Scheibenbogen C, Hanitsch LG

Abstract
The inability of patients with CVID to mount specific antibody responses to pathogens has raised concerns on the risk and severity of SARS-CoV-2 infection, but there might be a role for protective T cells in these patients. SARS-CoV-2 reactive T cells have been reported for SARS-CoV-2 unexposed healthy individuals. Until now, there is no data on T cell immunity to SARS-CoV-2 infection in CVID. This study aimed to evaluate reactive T cells to human endemic corona viruses (HCoV) and to study pre-existing SARS-CoV-2 reactive T cells in unexposed CVID patients. We evaluated SARS-CoV-2- and HCoV-229E and -OC43 reactive T cells in response to seven peptide pools, including spike and nucleocapsid (NCAP) proteins, in 11 unexposed CVID, 12 unexposed and 11 post COVID-19 healthy controls (HC). We further characterized reactive T cells by IFNγ, TNFα and IL-2 profiles. SARS-CoV-2 spike-reactive CD4+ T cells were detected in 7 of 11 unexposed CVID patients, albeit with fewer multifunctional (IFNγ/TNFα/IL-2) cells than unexposed HC. CVID patients had no SARS-CoV-2 NCAP reactive CD4+ T cells and less reactive CD8+ cells compared to unexposed HC. We observed a correlation between T cell reactivity against spike of SARS-CoV-2 and HCoVs in unexposed, but not post COVID-19 HC, suggesting cross-reactivity. T cell responses in post COVID-19 HC could be distinguished from unexposed HC by higher frequencies of triple-positive NCAP reactive CD4+ T cells. Taken together, SARS-CoV-2 reactive T cells are detectable in unexposed CVID patients albeit with lower recognition frequencies and polyfunctional potential. Frequencies of triple-functional reactive CD4+ cells might provide a marker to distinguish HCoV cross-reactive from SARS-CoV-2 specific T cell responses. Our data provides evidence, that anti-viral T cell immunity is not relevantly impaired in most CVID patients.

PMID: 33424856 [PubMed – in process]

A direct RT-qPCR approach to test large numbers of individuals for SARS-CoV-2.

January 12, 2021 By Manish Butte

A direct RT-qPCR approach to test large numbers of individuals for SARS-CoV-2.

PLoS One. 2020;15(12):e0244824

Authors: Maricic T, Nickel O, Aximu-Petri A, Essel E, Gansauge M, Kanis P, Macak D, Richter J, Riesenberg S, Bokelmann L, Zeberg H, Meyer M, Borte S, Pääbo S

Abstract
SARS-CoV-2 causes substantial morbidity and mortality in elderly and immunocompromised individuals, particularly in retirement homes, where transmission from asymptomatic staff and visitors may introduce the infection. Here we present a cheap and fast screening method based on direct RT-qPCR to detect SARS-CoV-2 in single or pooled gargle lavages (“mouthwashes”). This method detects individuals with large viral loads (Ct≤29) and we use it to test all staff at a nursing home daily over a period of three weeks in order to reduce the risk that the infection penetrates the facility. This or similar approaches can be implemented to protect hospitals, nursing homes and other institutions in this and future viral epidemics.

PMID: 33382830 [PubMed – indexed for MEDLINE]

Inherited GATA2 Deficiency Is Dominant by Haploinsufficiency and Displays Incomplete Clinical Penetrance.

January 9, 2021 By Manish Butte

Inherited GATA2 Deficiency Is Dominant by Haploinsufficiency and Displays Incomplete Clinical Penetrance.

J Clin Immunol. 2021 Jan 08;:

Authors: Oleaga-Quintas C, de Oliveira-Júnior EB, Rosain J, Rapaport F, Deswarte C, Guérin A, Sajjath SM, Zhou YJ, Marot S, Lozano C, Branco L, Fernández-Hidalgo N, Lew DB, Brunel AS, Thomas C, Launay E, Arias AA, Cuffel A, Monjo VC, Neehus AL, Marques L, Roynard M, Moncada-Vélez M, Gerçeker B, Colobran R, Vigué MG, Lopez-Herrera G, Berron-Ruiz L, Méndez NHS, O’Farrill Romanillos P, Le Voyer T, Puel A, Bellanné-Chantelot C, Ramirez KA, Lorenzo-Diaz L, Alejo NR, de Diego RP, Condino-Neto A, Mellouli F, Rodriguez-Gallego C, Witte T, Restrepo JF, Jobim M, Boisson-Dupuis S, Jeziorski E, Fieschi C, Vogt G, Donadieu J, Pasquet M, Vasconcelos J, Ardeniz FO, Martínez-Gallo M, Campos RA, Jobim LF, Martínez-Barricarte R, Liu K, Cobat A, Abel L, Casanova JL, Bustamante J

Abstract
PURPOSE: Germline heterozygous mutations of GATA2 underlie a variety of hematological and clinical phenotypes. The genetic, immunological, and clinical features of GATA2-deficient patients with mycobacterial diseases in the familial context remain largely unknown.
METHODS: We enrolled 15 GATA2 index cases referred for mycobacterial disease. We describe their genetic and clinical features including their relatives.
RESULTS: We identified 12 heterozygous GATA2 mutations, two of which had not been reported. Eight of these mutations were loss-of-function, and four were hypomorphic. None was dominant-negative in vitro, and the GATA2 locus was found to be subject to purifying selection, strongly suggesting a mechanism of haploinsufficiency. Three relatives of index cases had mycobacterial disease and were also heterozygous, resulting in 18 patients in total. Mycobacterial infection was the first clinical manifestation in 11 patients, at a mean age of 22.5 years (range: 12 to 42 years). Most patients also suffered from other infections, monocytopenia, or myelodysplasia. Strikingly, the clinical penetrance was incomplete (32.9% by age 40 years), as 16 heterozygous relatives aged between 6 and 78 years, including 4 older than 60 years, were completely asymptomatic.
CONCLUSION: Clinical penetrance for mycobacterial disease was found to be similar to other GATA2 deficiency-related manifestations. These observations suggest that other mechanisms contribute to the phenotypic expression of GATA2 deficiency. A diagnosis of autosomal dominant GATA2 deficiency should be considered in patients with mycobacterial infections and/or other GATA2 deficiency-related phenotypes at any age in life. Moreover, all direct relatives should be genotyped at the GATA2 locus.

PMID: 33417088 [PubMed – as supplied by publisher]

TREC Screening for WHIM Syndrome.

January 9, 2021 By Manish Butte

TREC Screening for WHIM Syndrome.

J Clin Immunol. 2021 Jan 07;:

Authors: Evans MO, Petersen MM, Khojah A, Jyonouchi SC, Edwardson GS, Khan YW, Connelly JA, Morris D, Majumdar S, McDermott DH, Walter JE, Murphy PM

Abstract
PURPOSE: T cell receptor excision circle (TREC) quantification is a recent addition to newborn screening (NBS) programs and is intended to identify infants with severe combined immunodeficiencies (SCID). However, other primary immunodeficiency diseases (PID) have also been identified as the result of TREC screening. We recently reported a newborn with a low TREC level on day 1 of life who was diagnosed with WHIM (warts, hypogammaglobulinemia, infections, myelokathexis) syndrome, a non-SCID primary immunodeficiency caused by mutations in the chemokine receptor CXCR4.
METHODS: We have now retrospectively reviewed the birth and clinical histories of all known WHIM infants born after the implementation of NBS for SCID.
RESULTS: We identified six infants with confirmed WHIM syndrome who also had TREC quantification on NBS. Three of the six WHIM infants had low TREC levels on NBS. All six patients were lymphopenic but only one infant had a T cell count below 1,500 cells/μL. The most common clinical manifestation was viral bronchiolitis requiring hospitalization. One infant died of complications related to Tetralogy of Fallot, a known WHIM phenotype.
CONCLUSION: The results suggest that WHIM syndrome should be considered in the differential diagnosis of newborns with low NBS TREC levels.
TRIAL REGISTRATION: Not applicable.

PMID: 33415666 [PubMed – as supplied by publisher]

[Advances in the Pathogenesis of Hereditary Angioedema].

January 9, 2021 By Manish Butte

[Advances in the Pathogenesis of Hereditary Angioedema].

Zhongguo Yi Xue Ke Xue Yuan Xue Bao. 2020 Oct;42(5):686-690

Authors: Cao Y, Liu S, Zhi Y

Abstract
Hereditary angioedema(HAE)is a rare,hereditary disease characterized by recurrent subcutaneous and submucosal edema.Known genes associated with the pathogenesis of HAE include C1 esterase inhibitor gene,FⅫ gene,plasminogen gene,and angiopoietin 1 gene.Based on the known gene mutations,this review analyzes the effects of these mutations on the functions of protein products to figure out the possible pathogenic mechanism,so as to provide references for further investigations on the pathogenesis of HAE and seeking new prevention and treatment approaches.

PMID: 33131525 [PubMed – indexed for MEDLINE]

Clinical and Immunological Features of 96 Moroccan Children with SCID Phenotype: Two Decades’ Experience.

January 8, 2021 By Manish Butte

Clinical and Immunological Features of 96 Moroccan Children with SCID Phenotype: Two Decades’ Experience.

J Clin Immunol. 2021 Jan 07;:

Authors: Benhsaien I, Ailal F, El Bakkouri J, Jeddane L, Ouair H, Admou B, Bouskraoui M, Hbibi M, Hida M, Amenzoui N, Jouhadi Z, El Hafidi N, Rada N, Benajiba N, Abilkassem R, Badou A, Bousfiha AA

Abstract
Severe combined immunodeficiency (SCID) is a heterogeneous group of primary immunodeficiency diseases (PIDs) characterized by a lack of autologous T lymphocytes. This severe PID is rare, but has a higher prevalence in populations with high rates of consanguinity. The epidemiological, clinical, and immunological features of SCIDs in Moroccan patients have never been reported. The aim of this study was to provide a clinical and immunological description of SCID in Morocco and to assess changes in the care of SCID patients over time. This cross-sectional retrospective study included 96 Moroccan patients referred to the national PID reference center at Casablanca Children’s Hospital for SCID over two decades, from 1998 to 2019. The case definition for this study was age < 2 years, with a clinical phenotype suggestive of SCID, and lymphopenia, with very low numbers of autologous T cells, according to the IUIS Inborn Errors of Immunity classification. Our sample included 50 male patients, and 66% of the patients were born to consanguineous parents. The median age at onset and diagnosis were 3.3 and 6.5 months, respectively. The clinical manifestations commonly observed in these patients were recurrent respiratory tract infection (82%), chronic diarrhea (69%), oral candidiasis (61%), and failure to thrive (65%). The distribution of SCID phenotypes was as follows: T-B-NK+ in 44.5%, T-B-NK- in 32%, T-B+NK- in 18.5%, and T-B+NK+ in 5%. An Omenn syndrome phenotype was observed in 15 patients. SCID was fatal in 84% in the patients in our cohort, due to the difficulties involved in obtaining urgent access to hematopoietic stem cell transplantation, which, nevertheless, saved 16% of the patients. The autosomal recessive forms of the clinical and immunological phenotypes of SCID, including the T-B-NK+ phenotype in particular, were more frequent than those in Western countries. A marked improvement in the early detection of SCID cases over the last decade was noted. Despite recent progress in SCID diagnosis, additional efforts are required, for genetic confirmation and particularly for HSCT.

PMID: 33411152 [PubMed – as supplied by publisher]

Safety and Tolerability of Subcutaneous IgPro20 at High Infusion Parameters in Patients with Primary Immunodeficiency: Findings from the Pump-Assisted Administration Cohorts of the HILO Study.

January 8, 2021 By Manish Butte

Safety and Tolerability of Subcutaneous IgPro20 at High Infusion Parameters in Patients with Primary Immunodeficiency: Findings from the Pump-Assisted Administration Cohorts of the HILO Study.

J Clin Immunol. 2021 Jan 06;:

Authors: Anderson JT, Bonagura VR, Cowan J, Hsu C, Mustafa SS, Patel NC, Routes JM, Sriaroon P, Vinh DC, Hofmann JH, Praus M, Rojavin MA

Abstract
PURPOSE: To evaluate the safety and tolerability of subcutaneous IgPro20 (Hizentra®, CSL Behring, King of Prussia, PA, USA) administered at high infusion parameters (> 25 mL and > 25 mL/h per injection site) in patients with primary immunodeficiency.
METHODS: The Hizentra® Label Optimization (HILO) study was an open-label, parallel-arm, non-randomized study (NCT03033745) of IgPro20 using a forced upward titration design for infusion parameters. Patients experienced with pump-assisted IgPro20 infusions received weekly IgPro20 infusions at a stable dose in the Pump-Assisted Volume Cohort (N = 15; 25-50 mL per injection site) and in the Pump-Assisted Flow Rate Cohort (N = 18; 25-100 mL/h per injection site). Responder rates (percentage of patients who successfully completed ≥ 75% of planned infusions), safety outcomes, and serum immunoglobulin G (IgG) trough levels were evaluated.
RESULTS: Responder rates were 86.7% (13/15, 25 mL) and 73.3% (11/15, 40 and 50 mL) in the Volume Cohort, and 77.8% (14/18, 25 and 50 mL/h), 66.7% (12/18, 75 mL/h), and 61.1% (11/18, 100 mL/h) in the Flow Rate Cohort. Infusion compliance was ≥ 90% in all patients in the Volume Cohort and in 83.3% of patients in the Flow Rate Cohort. The number of injection sites (Volume Cohort) and the infusion duration (Flow Rate Cohort) decreased with increasing infusion parameters. The rate of treatment-emergent adverse events per infusion was low (0.138 [Volume Cohort] and 0.216 [Flow Rate Cohort]). Serum IgG levels remained stable during the study.
CONCLUSION: Pump-assisted IgPro20 infusions are feasible at 50 mL and 100 mL/h per injection site in treatment-experienced patients, which may result in fewer injection sites and shorter infusion times.
TRIAL REGISTRATION: NCT03033745 ; registered January 27, 2017.

PMID: 33409867 [PubMed – as supplied by publisher]

Negative selection on human genes underlying inborn errors depends on disease outcome and both the mode and mechanism of inheritance.

January 8, 2021 By Manish Butte

Negative selection on human genes underlying inborn errors depends on disease outcome and both the mode and mechanism of inheritance.

Proc Natl Acad Sci U S A. 2021 Jan 19;118(3):

Authors: Rapaport F, Boisson B, Gregor A, Béziat V, Boisson-Dupuis S, Bustamante J, Jouanguy E, Puel A, Rosain J, Zhang Q, Zhang SY, Gleeson JG, Quintana-Murci L, Casanova JL, Abel L, Patin E

Abstract
Genetic variants underlying life-threatening diseases, being unlikely to be transmitted to the next generation, are gradually and selectively eliminated from the population through negative selection. We study the determinants of this evolutionary process in human genes underlying monogenic diseases by comparing various negative selection scores and an integrative approach, CoNeS, at 366 loci underlying inborn errors of immunity (IEI). We find that genes underlying autosomal dominant (AD) or X-linked IEI have stronger negative selection scores than those underlying autosomal recessive (AR) IEI, whose scores are not different from those of genes not known to be disease causing. Nevertheless, genes underlying AR IEI that are lethal before reproductive maturity with complete penetrance have stronger negative selection scores than other genes underlying AR IEI. We also show that genes underlying AD IEI by loss of function have stronger negative selection scores than genes underlying AD IEI by gain of function, while genes underlying AD IEI by haploinsufficiency are under stronger negative selection than other genes underlying AD IEI. These results are replicated in 1,140 genes underlying inborn errors of neurodevelopment. Finally, we propose a supervised classifier, SCoNeS, which predicts better than state-of-the-art approaches whether a gene is more likely to underlie an AD or AR disease. The clinical outcomes of monogenic inborn errors, together with their mode and mechanisms of inheritance, determine the levels of negative selection at their corresponding loci. Integrating scores of negative selection may facilitate the prioritization of candidate genes and variants in patients suspected to carry an inborn error.

PMID: 33408250 [PubMed – in process]

Genetic Screening of the Patients with Primary Immunodeficiency by Whole-Exome Sequencing.

January 7, 2021 By Manish Butte

Genetic Screening of the Patients with Primary Immunodeficiency by Whole-Exome Sequencing.

Pediatr Allergy Immunol Pulmonol. 2020 Mar;33(1):19-24

Authors: Erman B, Çipe F

Abstract
Background: Primary immunodeficiencies (PIDs) are a heterogeneous group of congenital disorders characterized by susceptibility to recurrent infections, allergy, malignancies and autoimmunity. The identification of disease-causing genetic defects is critically important for treatment options. In last decade, next-generation sequencing (NGS)-based methods has enabled the rapid genetic screening and the discovery of new genetic defects in PIDs. In this study, we investigated causative mutations in patients with PID by NGS. Methods: We applied whole-exome sequencing in 8 PID patients. Detected mutations by NGS were validated by Sanger sequencing. Results: We made a genetic diagnosis in 5 of 8 (63%) patients, including 3 novel disease-causing variants. The identified mutations were found in RAG1, RAG2, JAK3, RFXANK, and CYBA genes. Conclusions: Our results show that whole-exome sequencing can facilitate the genetic diagnosis of the patients with PID.

PMID: 33406023 [PubMed – as supplied by publisher]