Novel human neurodevelopmental and neurodegenerative disease associated with IRF2BPL gene variants-mechanisms and therapeutic avenues.

Recently a broad range of phenotypic abnormalities related to the neurodevelopmental and neurodegenerative disorder NEDAMSS (Neurodevelopmental Disorder with Regression, Abnormal Movements, Loss of Speech, and Seizures) have been associated with rare single-nucleotide polymorphisms (SNPs) or insertion and deletion variants (Indel) in the intron-less gene IRF2BPL. Up to now, 34 patients have been identified through whole exome sequencing carrying different heterozygous pathogenic variants spanning the intron-less gene from the first polyglutamine tract at the N-terminus to the C3HC4 RING domain of the C-terminus of the protein. As a result, the phenotypic spectrum of the patients is highly heterogeneous and ranges from abnormal neurocognitive development to severe neurodegenerative courses with developmental and seizure-related encephalopathies. While the treatment of IRF2BPL-related disorders has focused on alleviating the patient's symptoms by symptomatic multidisciplinary management, there has been no prospect of entirely relieving the symptoms of the individual patients. Yet, the recent advancement of CRISPR-Cas9-derived gene editing tools, leading to the generation of base editors (BEs) and prime editors (PEs), provide an encouraging new therapeutic avenue for treating NEDAMSS and other neurodevelopmental and neurodegenerative diseases, which contain SNPs or smaller Indels in post-mitotic cell populations of the central nervous system, due to its ability to generate site-specific DNA sequence modifications without creating double-stranded breaks, and recruiting the non-homologous DNA end joining repair mechanism.

Validation study of a new chemiluminescent singleplex IgE assay in a set of Italian allergic rhinitis patients.

BACKGROUND: The measurement of specific IgE to allergenic extracts and molecules in patients with allergic rhinitis (AR) is crucial for a precise diagnosis and further immunotherapy. Companies providing in vitro diagnostic methods in allergology continuously strive for the optimization and modernization of such methods. A new generation of automated allergy tests based on chemiluminescence detection and paramagnetic microparticles is now available, with possible advantages in sample volume, cost-effectiveness and avoidance of sample-related interference. OBJECTIVES: To test whether sIgE antibody levels obtained with a new singleplex chemiluminescent method have a good agreement with the corresponding results obtained with a "gold standard" test. METHODS: We tested sera from 368 AR patients. Specific IgE sera levels (kU/L) to a comprehensive panel of 15 allergen extracts and 6 molecules were tested with ImmunoCAP® (Thermo Fisher Scientific Inc, Phadia AB, Uppsala, Sweden) and NOVEOS™ (HYCOR® Biomedical, Garden Grove, CA, USA). We evaluated the qualitative and quantitative performance of the new NOVEOS system in matching the outcome of ImmunoCAP to each of the examined allergens. RESULTS: In relation to ImmunoCAP, the overall diagnostic sensitivity and specificity of sIgE tests with NOVEOS were 90.8% (95% CI = 88.6-92.7) and 96.2% (95% CI = 93.9-97.8), respectively. These values were higher when only molecules were considered (sensitivity = 98.7% [95% CI = 96.4%-99.7%]; specificity = 94.2% [95% CI = 88.4%-97.6%]) and lower when only extracts were considered (sensitivity = 87.6% [95% CI = 84.7%-90.2%]; specificity = 97% [95% CI = 94.4%-98.6%]). Spearman's correlation between the data set of both methods for a ≥ 0.1 kU/L cut-off was 0.84 (p < .001). CONCLUSIONS: The new singleplex NOVEOS system presented good results for qualitative and quantitative comparisons when testing specific serum IgE antibodies against a range of 21 allergens. This novel immunoassay system using only 4 µl of sample per test appears to be robust and reliable and can, therefore, be used as an aid in allergy diagnosis.

Validation of the analytical performance of the NOVEOS™ System, a system which improves upon the third-generation in vitro allergy testing technology.

Objectives Detection of allergen-specific immunoglobulin E (sIgE) is important for the diagnosis of allergy. IgE sensitization is commonly demonstrated in vivo by skin prick testing (SPT), or in vitro utilizing automated systems. Recently, HYCOR® Biomedical launched its new system for allergen sIgE testing called the NOVEOS™ Immunoanalyzer. This study aims to evaluate the analytical performance of the NOVEOS system in a bi-center study at Philipps-University Marburg (Site-1) and Charité Medical University Berlin (Site-2), respectively. Methods The analytical performance was evaluated based on the guidelines I/LA20-A3, EP5-A3, EP17-A2, EP6-A, EP7-A3, and EP9-A3 of the Clinical and Laboratory Standards Institute (CLSI). Results The conducted repeatability and within-laboratory precision tests provided acceptable performance with 3.0%-11.9% coefficient of variation across both sites. The limit of blank (LoB) and limit of detection (LoD) were <0.1 kU/L at both centers. A within-parameter linearity for all tested allergens was reported at both sites. Of note, no significant interference was observed for high levels of biotin, methylprednisolone, diphenhydramine, omalizumab, or ranitidine. Method comparison between the NOVEOS calibration and the latest World Health Organization (WHO) reference standard showed good agreement at both sites. Conclusions The results from the analytical performance of the NOVEOS allergen sIgE assay and instrument testing at both sites were comparable. Overall, a good precision and linearity as well as a detection limit <0.1 kU/L were observed, with minimal impact of common interfering substances on patient recoveries. The NOVEOS is calibrated to the latest WHO reference standard and adds benefits like a small sample size and para-magnetic microparticles that improve upon third-generation allergen sIgE assays' design and performance.

T Cell Repertoire During Ontogeny and Characteristics in Inflammatory Disorders in Adults and Childhood.

Since the first day of life, a newborn has to deal with various pathogens from the environment. While passive immune protection is provided by diaplacental maternal antibodies, the development of cellular immunity is ongoing. A mature immune system should be able not only to defend against pathogens, but should also be able to differentiate between self- and non-self-antigens. Dysregulation in the development of cellular immunity can lead to severe disorders like immunodeficiency, autoimmunity and chronic inflammation. In this review, we explain the role of T cell immunity in antigen detection and summarize the characteristics of a mature TCR repertoire as well as the current state of knowledge about the development of the TCR repertoire in ontogenesis. In addition, methods of assessments are outlined, with a focus on the advantages and disadvantages of advanced methods such as next generation sequencing. Subsequently, we provide an overview of various disorders occuring in early childhood like immunodeficiencies, autoimmunity, allergic diseases and chronic infections and outline known changes in the TCR repertoire. Finally, we summarize the latest findings and discuss current research gaps as well as potential future developments.