Characterization of immune function and analysis of <i>RAG</i> gene mutations in Omenn syndrome and related disorders

Wada, Taizo; Takei, Kenkichi; Kudo, Masatoshi; Shimura, Satoshi; Kasahara, Yoshihito; Koizumi, Satoshi; Kawa‐Ha, Keisei; Ishida, Yasushi; Imashuku, Shinsaku; Seki, Hidetoshi; Yachie, Akihiro

doi:10.1046/j.1365-2249.2000.01101.x

Cited by 40 publications

(22 citation statements)

References 26 publications

(35 reference statements)

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“…These samples were sequenced and a single nucleotide polymorphism from A to G was found at position 2571, which has been described previously. 8 Furthermore, in our study we detected another single transitional base change localized at position 301 in the sequence of the RAJI cell line (human Burkitt lymphoma). However, this abnormal band did not correspond to an amino acid change since both codons codified a Proline.…”

supporting

confidence: 51%

Sequence conservation of RAG-1 and RAG-2 genes in hematologic malignancies

et al. 2002

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The diversity of the immune repertoire is due to a physiological process of somatic gene rearrangement directed by the V(D)J recombinase. The products of the RAG-1 and RAG-2 genes drive the molecular process of assembly of immunoglobulin and T cell antigen receptor genes. The expression of RAG genes is not restricted to immature lymphocyte populations in the thymus and bone marrow but they are also functional in germinal center B cells. [1][2][3][4] It has been postulated that certain chromosomal translocations could be attributed to an illegitimate recombinase activity of this enzymatic complex. Earlier studies have demonstrated that RAG-1 is expressed in a stage-specific manner among acute lymphoblastic leukemia(ALL)/lymphoblastic lymphoma (LBL) cells. 5 Schwarz et al 6 demonstrated the absence of mature B and T cells owing to truncations of the RAG-1 or RAG-2 genes by missense mutations in the active core of the proteins that eliminate their function and lead to an immunodeficiency.A mutational analysis of the entire coding region of the RAG-1 and RAG-2 genes was performed in a series of different types of hematologic malignancies. Cell lines tested and purchased from DSMZ were: NALM-6 (human B cell precursor leukemia), HEL (human erythroleukemia), RAJI (human Burkitt lymphoma), MV-4,11(human acute monocytic leukemia which carries a 4;11 translocation), SU-DHL-1 (human anaplastic large cell lymphoma which carries the t(2;5)(p23;q35) NPM-ALK fusion gene), DAUDI (human Burkitt lymphoma) and NB-4 (human acute promyelocytic leukemia which carries the t(15;17) PML-RARA fusion gene). Clinical samples harboring well characterized molecular lesions were also analyzed: six acute lymphoblastic leukemias with bcr/abl rearrangements, five anaplastic large cell lymphomas with NPM/ALK rearrangements, five follicular lymphomas carrying the bcl2/J H rearrangement, 14 acute leukemias with MLL rearrangements, nine acute lymphoblastic leukemias and follicular lymphomas with p53 mutations and 11 acute lymphoblastic leukemias with TEL/AML-1 rearrangements. Mutational analysis of RAG-1 gene was performed following the protocol described in an earlier work 7 and RAG-2 gene was studied using seven sets of overlapping oligonucleotide primers covering the coding sequence (primers and PCR conditions are provided on request).The multiple PCR-SSCP analysis of the RAG-1 gene detected shifted bands in four cases with the following diagnosis: two bcr/abl+ ALL, one MLL+ AML and one case diagnosed with FL. These samples were sequenced and a single nucleotide polymorphism from A to G was found at position 2571, which has been described previously. 8 Furthermore, in our study we detected another single transitional base change localized at position 301 in the sequence of the RAJI cell line (human Burkitt lymphoma). However, this abnormal band did not correspond to an amino acid change since both codons codified a Proline. This sequence change was present in a heterozygous state (Figure 1).We were unable to detect sequence changes in the RAG-2 g...

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confidence: 51%

Sequence conservation of RAG-1 and RAG-2 genes in hematologic malignancies

et al. 2002

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“…While double mutations of murine GG 389-390 (corresponding to human residues 392-393) have a dramatic impact on nonamer binding, 15 single amino acid substitutions in the NBD allow for residual V(D)J recombination activity and have been identified in patients with OS. 3,16 The R561H mutation of patient 4 has been previously reported. 3,6 It affects the Rag-2 interacting domain of Rag-1 and reduces V(D)J recombination activity by 3-to 4-fold.…”

Section: Resultsmentioning

confidence: 76%

Lack of iNKT cells in patients with combined immune deficiency due to hypomorphic RAG mutations

Matangkasombut

Pichavant

Saez

et al. 2008

Blood

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IntroductionOmenn syndrome (OS) is a combined immunodeficiency characterized by early-onset erythroderma, lymphadenopathy, hepatosplenomegaly, and severe infections. Patients with OS have a variable number of autologous, oligoclonal, and activated T cells that infiltrate and damage target tissues. 1,2 OS may be due to heterogeneous gene defects that impair, but do not abolish, thymic T-cell development. In particular, hypomorphic mutations of the RAG1 or RAG2 genes, involved in V(D)J recombination, are a common cause for OS. [3][4][5] The same defects may lead to a spectrum of clinical and immunologic phenotypes that also include typical T Ϫ B Ϫ severe combined immune deficiency (SCID) or leaky SCID with residual presence of activated T cells, in the absence of typical features of OS. 4,6 The clinical and pathological features of OS are suggestive of T-cell-mediated autoimmunity. In keeping with this hypothesis, we have found that expression of autoimmune regulator (AIRE) and of AIRE-dependent tissue-specific transcripts is reduced in the thymus from patients with OS, possibly contributing to impaired central tolerance. 7 In addition, defects of regulatory T cells have been also hypothesized in patients with OS. 8 Both abnormalities have been confirmed in a newly generated murine model of OS. 9 However, the possible contributory role of other immunomodulatory components in determining the phenotype of OS has not been carefully evaluated.Natural killer T (NKT) cells represent a population of cells with significant immunomodulatory properties. 10 In humans, most NKT cells recognize glycolipids presented in the context of CD1d molecules and express NK-cell markers along with an invariant T-cell receptor (TCR) with a V␣24-J␣18 rearrangement. NKT cells expressing the invariant TCR (iNKT) can be identified using ␣-galactosylceramide (␣-GalCer)-loaded CD1d tetramers. 11 iNKT cells are generated in the thymus from CD4 ϩ CD8 ϩ thymocytes that rearrange the invariant TCR and are directed to the NKT lineage following cognate interactions with CD1d-expressing cortical thymocytes. 12,13 Therefore, NKT cell development is absolutely dependent on V(D)J recombination, consistent with the observation that iNKT cells are severely reduced in a Rag2 knock-in mouse model of OS. 9 In this study, we provide the first evidence that iNKT cells are absent in peripheral blood of patients with hypomorphic RAG mutations, a situation where substantial numbers of autoreactive T cells develop. We speculate that the absence of iNKT cells may contribute to the pathophysiology of OS. Methods PatientsFive unrelated patients with hypomorphic RAG defects were studied; 4 of them (patients 1, 2, 3, and 5) had typical OS, whereas patient 4 had the phenotype of T ϩ B Ϫ leaky SCID (Table 1). Informed consent was obtained in accordance with the Declaration of Helsinki and according to protocols approved by Children's Hospital, Boston; the Department of Pediatrics, University, Brescia, Italy; and the Department of Pediatrics, Tor Vergata University, Rome, ...

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“…pH2V14CJ construct was derived 38 (black on gray), Wada and coworkers 39 (white on black), and this report (black on white). All the mutations are located within the active core (amino acids 384-1009) of the protein and some of them involve the homeodomain or one of the RAG2 interaction domains.…”

Section: V␤14-rss Sequence Analysis and Cloningmentioning

confidence: 89%

“…27 Indeed, mutations in both RAG1 and RAG2 genes were described in patients with OS. 32,[38][39][40] We report here the analysis of RAG1/2 genes in a series of 9 OS patients. Three of these mutations, causing OS in some patients, were also associated with typical T-B-SCID condition in other patients.…”

Section: Introductionmentioning

confidence: 99%