RAG2
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The recombination-activating genes (RAG) 1 and 2 are indispensable for diversifying the primary B cell receptor repertoire and pruning self-reactive clones via receptor editing in the bone marrow; however, the impact of RAG1/RAG2 on peripheral tolerance is unknown. Partial RAG deficiency (pRD) manifesting with late-onset immune dysregulation represents an 'experiment of nature' to explore this conundrum. By studying B cell development and subset-specific repertoires in pRD, we demonstrate that reduced RAG activity impinges on peripheral tolerance through the generation of a restricted primary B cell repertoire, persistent antigenic stimulation and an inflammatory milieu with elevated B cell-activating factor. This unique environment gradually provokes profound B cell dysregulation with widespread activation, remarkable extrafollicular maturation and persistence, expansion and somatic diversification of self-reactive clones. Through the model of pRD, we reveal a RAG-dependent 'domino effect' that impacts stringency of tolerance and B cell fate in the periphery.
- MeSH
- B-lymfocyty * MeSH
- buněčná diferenciace MeSH
- DNA vazebné proteiny * nedostatek genetika MeSH
- homeodoménové proteiny * genetika MeSH
- imunologická tolerance MeSH
- jaderné proteiny * nedostatek MeSH
- lidé MeSH
- počet lymfocytů MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Research Support, N.I.H., Extramural MeSH
- Research Support, N.I.H., Intramural MeSH
SCID (Severe combined immunodeficiency) neboli těžký kombinovaný imunodeficit je klinicky i geneticky heterogenní skupina nejzávažnějších vrozených poruch imunity. Toto vzácné onemocnění vede především k selhávání obrany proti infekcím na základě abnormálního vývoje lymfocytů a jejich funkcí. Jako život ohrožující stav vyžaduje co nejčasnější diagnostiku k zajištění adekvátního managementu směřujícímu k časné transplantaci kmenových buněk krvetvorby. Kromě klasických forem SCID, manifestujících se v časném kojeneckém věku, existují také formy, jež se mohou projevit později a/nebo mohou mít mírnější klinické příznaky. V tomto článku prezentujeme kazuistiku 5měsíčního kojence s autosomálně recesivním RAG2 SCID s atypickým fenotypem, který je jediným diagnostikovaným pacientem se SCID v České republice v letech 2018 a 2019.
Severe combined immunodeficiency (SCID) is clinically and genetically heterogeneous group of the most severe inborn errors of immunity. The disease typically presents as a failure of antimicrobial defences due to various defects of lymphocyte development and functions. Being a life-threatening condition, SCID requires a prompt diagnosis in order to implement an appropriate management aimed towards early hematopoietic stem cell transplantation. Besides the classic forms of SCID, atypical or leaky phenotypes exist, that may manifest later in life or/and with milder symptoms. In this report, we describe a 5-months-old infant with autosomal recessive atypical RAG2 SCID, who is the only patient diagnosed with SCID in the Czech Republic in the years 2018 and 2019.
- Klíčová slova
- SCID screening, SCID,
- MeSH
- kojenec MeSH
- lidé MeSH
- lymfopenie diagnóza etiologie MeSH
- těžká kombinovaná imunodeficience * diagnóza terapie MeSH
- transplantace kostní dřeně metody MeSH
- výsledek terapie MeSH
- Check Tag
- kojenec MeSH
- lidé MeSH
- mužské pohlaví MeSH
- Publikační typ
- kazuistiky MeSH
- práce podpořená grantem MeSH
Background: Variants in recombination-activating genes (RAG) are common genetic causes of autosomal recessive forms of combined immunodeficiencies (CID) ranging from severe combined immunodeficiency (SCID), Omenn syndrome (OS), leaky SCID, and CID with granulomas and/or autoimmunity (CID-G/AI), and even milder presentation with antibody deficiency. Objective: We aim to estimate the incidence, clinical presentation, genetic variability, and treatment outcome with geographic distribution of patients with the RAG defects in populations inhabiting South, West, and East Slavic countries. Methods: Demographic, clinical, and laboratory data were collected from RAG-deficient patients of Slavic origin via chart review, retrospectively. Recombinase activity was determined in vitro by flow cytometry-based assay. Results: Based on the clinical and immunologic phenotype, our cohort of 82 patients from 68 families represented a wide spectrum of RAG deficiencies, including SCID (n = 20), OS (n = 37), and LS/CID (n = 25) phenotypes. Sixty-seven (81.7%) patients carried RAG1 and 15 patients (18.3%) carried RAG2 biallelic variants. We estimate that the minimal annual incidence of RAG deficiency in Slavic countries varies between 1 in 180,000 and 1 in 300,000 live births, and it may vary secondary to health care disparities in these regions. In our cohort, 70% (n = 47) of patients with RAG1 variants carried p.K86Vfs*33 (c.256_257delAA) allele, either in homozygous (n = 18, 27%) or in compound heterozygous (n = 29, 43%) form. The majority (77%) of patients with homozygous RAG1 p.K86Vfs*33 variant originated from Vistula watershed area in Central and Eastern Poland, and compound heterozygote cases were distributed among all Slavic countries except Bulgaria. Clinical and immunological presentation of homozygous RAG1 p.K86Vfs*33 cases was highly diverse (SCID, OS, and AS/CID) suggestive of strong influence of additional genetic and/or epigenetic factors in shaping the final phenotype. Conclusion: We propose that RAG1 p.K86Vfs*33 is a founder variant originating from the Vistula watershed region in Poland, which may explain a high proportion of homozygous cases from Central and Eastern Poland and the presence of the variant in all Slavs. Our studies in this cohort of RAG1 founder variants confirm that clinical and immunological phenotypes only partially depend on the underlying genetic defect. As access to HSCT is improving among RAG-deficient patients in Eastern Europe, we anticipate improvements in survival.
- MeSH
- běloši * MeSH
- dítě MeSH
- DNA vazebné proteiny genetika MeSH
- fenotyp MeSH
- frekvence genu MeSH
- genotyp * MeSH
- homeodoménové proteiny genetika MeSH
- incidence MeSH
- jaderné proteiny genetika MeSH
- kojenec MeSH
- lidé MeSH
- mladiství MeSH
- mladý dospělý MeSH
- novorozenec MeSH
- polymorfismus genetický MeSH
- předškolní dítě MeSH
- retrospektivní studie MeSH
- sekvenční delece genetika MeSH
- syndromy imunologické nedostatečnosti genetika MeSH
- výsledek terapie MeSH
- Check Tag
- dítě MeSH
- kojenec MeSH
- lidé MeSH
- mladiství MeSH
- mladý dospělý MeSH
- mužské pohlaví MeSH
- novorozenec MeSH
- předškolní dítě MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Research Support, N.I.H., Extramural MeSH
- Research Support, N.I.H., Intramural MeSH
The EuroFlow PID consortium developed a set of flow cytometry tests for evaluation of patients with suspicion of primary immunodeficiency (PID). In this technical report we evaluate the performance of the SCID-RTE tube that explores the presence of recent thymic emigrants (RTE) together with T-cell activation status and maturation stages and discuss its applicability in the context of the broader EuroFlow PID flow cytometry testing algorithm for diagnostic orientation of PID of the lymphoid system. We have analyzed peripheral blood cells of 26 patients diagnosed between birth and 2 years of age with a genetically defined primary immunodeficiency disorder: 15 severe combined immunodeficiency (SCID) patients had disease-causing mutations in RAG1 or RAG2 (n = 4, two of them presented with Omenn syndrome), IL2RG (n = 4, one of them with confirmed maternal engraftment), NHEJ1 (n = 1), CD3E (n = 1), ADA (n = 1), JAK3 (n = 3, two of them with maternal engraftment) and DCLRE1C (n = 1) and 11 other PID patients had diverse molecular defects [ZAP70 (n = 1), WAS (n = 2), PNP (n = 1), FOXP3 (n = 1), del22q11.2 (DiGeorge n = 4), CDC42 (n = 1) and FAS (n = 1)]. In addition, 44 healthy controls in the same age group were analyzed using the SCID-RTE tube in four EuroFlow laboratories using a standardized 8-color approach. RTE were defined as CD62L+CD45RO-HLA-DR-CD31+ and the activation status was assessed by the expression of HLA-DR+. Naïve CD8+ T-lymphocytes and naïve CD4+ T-lymphocytes were defined as CD62L+CD45RO-HLA-DR-. With the SCID-RTE tube, we identified patients with PID by low levels or absence of RTE in comparison to controls as well as low levels of naïve CD4+ and naïve CD8+ lymphocytes. These parameters yielded 100% sensitivity for SCID. All SCID patients had absence of RTE, including the patients with confirmed maternal engraftment or oligoclonally expanded T-cells characteristic for Omenn syndrome. Another dominant finding was the increased numbers of activated CD4+HLA-DR+ and CD8+HLA-DR+ lymphocytes. Therefore, the EuroFlow SCID-RTE tube together with the previously published PIDOT tube form a sensitive and complete cytometric diagnostic test suitable for patients suspected of severe PID (SCID or CID) as well as for children identified via newborn screening programs for SCID with low or absent T-cell receptor excision circles (TRECs).
- MeSH
- HLA-DR antigeny analýza MeSH
- imunofenotypizace metody MeSH
- kojenec MeSH
- lidé MeSH
- novorozenec MeSH
- předškolní dítě MeSH
- primární imunodeficience diagnóza imunologie MeSH
- průtoková cytometrie metody MeSH
- T-lymfocyty imunologie MeSH
- těžká kombinovaná imunodeficience imunologie MeSH
- thymus imunologie MeSH
- Check Tag
- kojenec MeSH
- lidé MeSH
- mužské pohlaví MeSH
- novorozenec MeSH
- předškolní dítě MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
We find that cardiac group 2 innate lymphoid cells (ILC2s) are essential for the development of IL-33-induced eosinophilic pericarditis. We show a pathogenic role for ILC2s in cardiac inflammation, in which ILC2s activated by IL-33 drive the development of eosinophilic pericarditis in collaboration with cardiac fibroblasts. ILCs, not T and B cells, are required for the development of pericarditis. ILC2s transferred to the heart of Rag2-/-Il2rg-/- mice restore their susceptibility to eosinophil infiltration. Moreover, ILC2s direct cardiac fibroblasts to produce eotaxin-1. We also find that eosinophils reside in the mediastinal cavity and that eosinophils transferred to the mediastinal cavity of eosinophil-deficient ΔdblGATA1 mice following IL-33 treatment migrate to the heart. Thus, the serous cavities may serve as a reservoir of cardiac-infiltrating eosinophils. In humans, patients with pericarditis show higher amounts of ILCs in pericardial fluid than do healthy controls and patients with other cardiac diseases. We demonstrate that ILCs play a critical role in pericarditis.
- MeSH
- chemokin CCL11 genetika metabolismus MeSH
- eozinofily účinky léků patologie MeSH
- fibroblasty účinky léků metabolismus MeSH
- funkční vyšetření srdce účinky léků MeSH
- interleukin 33 farmakologie MeSH
- interleukin-1 receptor-like 1 protein nedostatek metabolismus MeSH
- interleukin-5 metabolismus MeSH
- lidé MeSH
- lymfocyty účinky léků imunologie MeSH
- mediastinum patologie MeSH
- myši inbrední BALB C MeSH
- náchylnost k nemoci MeSH
- perikarditida genetika imunologie patofyziologie MeSH
- pohyb buněk účinky léků MeSH
- přirozená imunita * účinky léků MeSH
- regulace genové exprese účinky léků MeSH
- signální transdukce účinky léků MeSH
- srdce účinky léků patofyziologie MeSH
- upregulace účinky léků MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Research Support, N.I.H., Extramural MeSH
Cryptic genetic diversity and erroneous morphological species determination represent frequent problems in biodiversity research. Here, examination of 138 specimens of Synodontis (Mochokidae, Siluriformes) from the Nile River and Lake Turkana revealed the presence of both S. schall-like and S. frontosus-like morphotypes, with a phenotypic gradient between them. We concluded phylogenetic and population genetic analyses based on two mitochondrial and one nuclear marker including 131 coxI (565 bp), 96 cytb (973 bp) and 19 RAG2 (896 bp) sequences from the Nile-Turkana population, plus additional GenBank data of Synodontis spp. Whilst nuclear data were inconclusive, mitochondrial sequences suggested that both morphotypes and intermediate forms are conspecific. The results imply probable synonymy of S. frontosus with S. schall. Conversely, a strong biogeographical signal was revealed among widely distributed and supposedly conspecific S. schall-like catfish of the Nilo-Sudanian ichthyological province. Synodontis schall sensu stricto (=Eastern clade), as defined by type locality in the Nile, is apparently restricted to the eastern part of the Nilo-Sudanian ichthyological province (e.g. Nile, Turkana, Chad). Synodontis schall Western clade (Senegambia, Niger, Chad) most probably represents a cryptic taxon, unrecognized thus far due to the absence of distinctive morphological differences.
- MeSH
- Bayesova věta MeSH
- biodiverzita * MeSH
- cytochromy b klasifikace genetika MeSH
- fylogeneze MeSH
- haplotypy MeSH
- populační genetika MeSH
- respirační komplex IV klasifikace genetika MeSH
- sumci klasifikace genetika MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Diet is a major factor determining gut microbiota composition and perturbances in this complex ecosystem are associated with the inflammatory bowel disease (IBD). Here, we used gnotobiotic approach to analyze, how interaction between diet rich in proteins and gut microbiota influences the sensitivity to intestinal inflammation in murine model of ulcerative colitis. We found that diet rich in animal protein (aHPD) exacerbates acute dextran sulfate sodium (DSS)-induced colitis while diet rich in plant protein (pHPD) does not. The deleterious effect of aHPD was also apparent in chronic DSS colitis and was associated with distinct changes in gut bacteria and fungi. Therefore, we induced acute DSS-colitis in germ-free mice and transferred gut microbiota from aCD or aHPD fed mice to find that this effect requires presence of microbes and aHPD at the same time. The aHPD did not change the number of regulatory T cells or Th17 cells and still worsened the colitis in immuno-deficient RAG2 knock-out mice suggesting that this effect was not dependent on adaptive immunity. The pro-inflammatory effect of aHPD was, however, abrogated when splenic macrophages were depleted with clodronate liposomes. This treatment prevented aHPD induced increase in colonic Ly-6Chigh pro-inflammatory monocytes, but the ratio of resident Ly-6C-/low macrophages was not changed. These data show that the interactions between dietary protein of animal origin and gut microbiota increase sensitivity to intestinal inflammation by promoting pro-inflammatory response of monocytes.
- MeSH
- adaptivní imunita imunologie MeSH
- buňky Th17 imunologie metabolismus MeSH
- dieta škodlivé účinky MeSH
- dietní proteiny aplikace a dávkování škodlivé účinky MeSH
- DNA vazebné proteiny metabolismus MeSH
- kolitida imunologie metabolismus patologie MeSH
- kolon imunologie metabolismus patologie MeSH
- makrofágy imunologie metabolismus patologie MeSH
- modely nemocí na zvířatech MeSH
- monocyty imunologie metabolismus patologie MeSH
- myši inbrední BALB C MeSH
- myši knockoutované MeSH
- myši MeSH
- regulační T-lymfocyty imunologie metabolismus MeSH
- střeva imunologie patologie MeSH
- střevní mikroflóra imunologie fyziologie MeSH
- zánět imunologie metabolismus patologie MeSH
- zvířata MeSH
- Check Tag
- myši MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
The understanding of the diversity of species in the Palearctic and the processes that have generated it is still weak for large parts of the arid areas of North Africa and Arabia. Reptiles are among their most remarkable representatives, with numerous groups well adapted to the diverse environments. The Ptyodactylus geckos are a strictly rock-dwelling genus with homogeneous morphology distributed across mountain formations and rocky plateaus from the western African ranges in Mauritania and the Maghreb to the eastern tip of the Arabian Peninsula, with an isolated species in southern Pakistan. Here, we use a broad sampling of 378 specimens, two mitochondrial (12S and cytb) and four nuclear (c-mos, MC1R, ACM4, RAG2) markers in order to obtain the first time-calibrated molecular phylogeny of the genus and place its diversification in a temporal framework. The results reveal high levels of intraspecific variability, indicative of undescribed diversity, and they do not support the monophyly of one species (P. ragazzii). Ptyodactylus species are allopatric across most of their range, which may relate to their high preference for the same type of structural habitat. The onset of their diversification is estimated to have occurred in the Late Oligocene, while that of several deep clades in the phylogeny took place during the Late Miocene, a period when an increase in aridification in North Africa and Arabia initiated.
- MeSH
- Bayesova věta MeSH
- fylogeneze * MeSH
- fylogeografie MeSH
- ještěři klasifikace genetika MeSH
- mitochondriální DNA genetika MeSH
- pravděpodobnostní funkce MeSH
- sekvenční analýza DNA MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Geografické názvy
- severní Afrika MeSH
- Střední východ MeSH
A molecular phylogeny of the sphaerodactylid geckos of the genus Pristurus is inferred based on an alignment of 1845 base pairs (bp) of concatenated mitochondrial (12S) and nuclear (acm4, cmos, rag1 and rag2) genes for 80 individuals, representing 18 of the 23-26 species, and the three subspecies of P. rupestris. The results indicate that P. rupestris is polyphyletic and includes two highly divergent clades: the eastern clade, found in coastal Iran and throughout the Hajar Mountain range in northern Oman and eastern UAE; and the western clade, distributed from central coastal Oman, through Yemen, Saudi Arabia and north to southern Jordan. Inferred haplotype networks for the four nuclear genes show that the eastern and western clades of "P. rupestris" are highly differentiated and do not share any alleles. Moreover, although the two clades are differentiated by a morphological multivariate analysis, no one character or set of characters was found to be diagnostic. Based on the molecular analysis of specimens from the type locality of P. rupestris rupestris, the name P. rupestris is applied to the eastern clade. The name that should apply to the western clade cannot be clarified until morphological and genetic data for "P. rupestris" is available from the vicinity of Bosaso, Somalia, and therefore we refer to it as Pristurus sp. 1. The phylogenetic tree of Pristurus supports the hypothesis that P. celerrimus is sister to all the other species in the analyses and that the Socotra Archipelago was independently colonized a minimum of two times.
- MeSH
- fylogeneze * MeSH
- ještěři klasifikace genetika MeSH
- mitochondriální DNA genetika MeSH
- rozšíření zvířat MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Geografické názvy
- Somálsko MeSH
- Střední východ MeSH
BACKGROUND: V(D)J recombination takes place during lymphocyte development to generate a large repertoire of T- and B-cell receptors. Mutations in recombination-activating gene 1 (RAG1) and RAG2 result in loss or reduction of V(D)J recombination. It is known that different mutations in RAG genes vary in residual recombinase activity and give rise to a broad spectrum of clinical phenotypes. OBJECTIVE: We sought to study the immunologic mechanisms causing the clinical spectrum of RAG deficiency. METHODS: We included 22 patients with similar RAG1 mutations (c.519delT or c.368_369delAA) resulting in N-terminal truncated RAG1 protein with residual recombination activity but presenting with different clinical phenotypes. We studied precursor B-cell development, immunoglobulin and T-cell receptor repertoire formation, receptor editing, and B- and T-cell numbers. RESULTS: Clinically, patients were divided into 3 main categories: T(-)B(-) severe combined immunodeficiency, Omenn syndrome, and combined immunodeficiency. All patients showed a block in the precursor B-cell development, low B- and T-cell numbers, normal immunoglobulin gene use, limited B- and T-cell repertoires, and slightly impaired receptor editing. CONCLUSION: This study demonstrates that similar RAG mutations can result in similar immunobiological effects but different clinical phenotypes, indicating that the level of residual recombinase activity is not the only determinant for clinical outcome. We postulate a model in which the type and moment of antigenic pressure affect the clinical phenotypes of these patients.
- MeSH
- B-lymfocyty imunologie metabolismus MeSH
- exprese genu MeSH
- fenotyp * MeSH
- genetické asociační studie * MeSH
- genotyp MeSH
- homeodoménové proteiny genetika metabolismus MeSH
- hypervariabilní oblasti genetika MeSH
- kojenec MeSH
- lidé MeSH
- mutace * MeSH
- novorozenec MeSH
- počet lymfocytů MeSH
- předškolní dítě MeSH
- T-lymfocyty imunologie metabolismus MeSH
- těžká kombinovaná imunodeficience diagnóza genetika imunologie metabolismus MeSH
- těžké řetězce imunoglobulinů genetika MeSH
- V(D)J rekombinace MeSH
- Check Tag
- kojenec MeSH
- lidé MeSH
- novorozenec MeSH
- předškolní dítě MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH