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Kubagawa H, Mahmoudi Aliabadi P, Al-Qaisi K, Jani PK, Honjo K, Izui S, Radbruch A, Melchers F. Functions of IgM fc receptor (FcµR) related to autoimmunity. Autoimmunity 2024; 57:2323563. [PMID: 38465789 DOI: 10.1080/08916934.2024.2323563] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2023] [Accepted: 02/20/2024] [Indexed: 03/12/2024]
Abstract
Unlike Fc receptors for switched immunoglobulin (Ig) isotypes, Fc receptor for IgM (FcµR) is selectively expressed by lymphocytes. The ablation of the FcµR gene in mice impairs B cell tolerance as evidenced by concomitant production of autoantibodies of IgM and IgG isotypes. In this essay, we reiterate the autoimmune phenotypes observed in mutant mice, ie IgM homeostasis, dysregulated humoral immune responses including autoantibodies, and Mott cell formation. We also propose the potential phenotypes in individuals with FCMR deficiency and the model for FcµR-mediated regulation of self-reactive B cells.
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Affiliation(s)
| | | | | | - Peter K Jani
- Deutsches Rheuma-Forschungszentrum Berlin, Berlin, Germany
| | - Kazuhito Honjo
- Department of Medicine, School of Medicine, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Shozo Izui
- Department of Pathology and Immunology, University of Geneva, Geneva, Switzerland
| | | | - Fritz Melchers
- Deutsches Rheuma-Forschungszentrum Berlin, Berlin, Germany
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2
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Aubin AM, Vdovenko D, Collin R, Balmer L, Coderre L, Morahan G, Lombard-Vadnais F, Lesage S. Variations in the germinal center response revealed by genetically diverse mouse strains. Immunol Cell Biol 2024. [PMID: 39318030 DOI: 10.1111/imcb.12823] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2024] [Revised: 08/16/2024] [Accepted: 09/10/2024] [Indexed: 09/26/2024]
Abstract
The humoral response is complex and involves multiple cellular populations and signaling pathways. Bacterial and viral infections, as well as immunization regimens, can trigger this type of response, promoting the formation of microanatomical cellular structures called germinal centers (GCs). GCs formed in secondary lymphoid organs support the differentiation of high-affinity plasma cells and memory B cells. There is growing evidence that the quality of the humoral response is influenced by genetic variants. Using 12 genetically divergent mouse strains, we assessed the impact of genetics on GC cellular traits. At steady state, in the spleen, lymph nodes and Peyer's patches, we quantified GC B cells, plasma cells and follicular helper T cells. These traits were also quantified in the spleen of mice following immunization with a foreign antigen, namely, sheep red blood cells, in addition to the number and size of GCs. We observed both strain- and organ-specific variations in cell type abundance, as well as for GC number and size. Moreover, we find that some of these traits are highly heritable. Importantly, the results of this study inform on the impact of genetic diversity in shaping the GC response and identify the traits that are the most impacted by genetic background.
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Affiliation(s)
- Anne-Marie Aubin
- Immunologie-Oncologie, Centre de Recherche de l'Hôpital Maisonneuve-Rosemont, Montréal, QC, Canada
- Département de Microbiologie, Infectiologie et Immunologie, Université de Montréal, Montréal, QC, Canada
| | - Daria Vdovenko
- Immunologie-Oncologie, Centre de Recherche de l'Hôpital Maisonneuve-Rosemont, Montréal, QC, Canada
- Département de Microbiologie, Infectiologie et Immunologie, Université de Montréal, Montréal, QC, Canada
| | - Roxanne Collin
- Immunologie-Oncologie, Centre de Recherche de l'Hôpital Maisonneuve-Rosemont, Montréal, QC, Canada
- Département de Microbiologie, Infectiologie et Immunologie, Université de Montréal, Montréal, QC, Canada
| | - Lois Balmer
- Centre for Diabetes Research, Harry Perkins Institute of Medical Research, Nedlands, WA, Australia
- Centre for Medical Research, University of Western Australia, Perth, WA, Australia
- School of Medical and Health Science, Edith Cowan University, Perth, WA, Australia
| | - Lise Coderre
- Immunologie-Oncologie, Centre de Recherche de l'Hôpital Maisonneuve-Rosemont, Montréal, QC, Canada
- Département de Microbiologie, Infectiologie et Immunologie, Université de Montréal, Montréal, QC, Canada
| | - Grant Morahan
- Centre for Diabetes Research, Harry Perkins Institute of Medical Research, Nedlands, WA, Australia
- Centre for Medical Research, University of Western Australia, Perth, WA, Australia
| | - Félix Lombard-Vadnais
- Immunologie-Oncologie, Centre de Recherche de l'Hôpital Maisonneuve-Rosemont, Montréal, QC, Canada
| | - Sylvie Lesage
- Immunologie-Oncologie, Centre de Recherche de l'Hôpital Maisonneuve-Rosemont, Montréal, QC, Canada
- Département de Microbiologie, Infectiologie et Immunologie, Université de Montréal, Montréal, QC, Canada
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Honjo K, Kubagawa Y, Suzuki Y, Takagi M, Ohno H, Bucy RP, Izui S, Kubagawa H. Enhanced auto-antibody production and Mott cell formation in FcμR-deficient autoimmune mice. Int Immunol 2014; 26:659-72. [PMID: 24994818 DOI: 10.1093/intimm/dxu070] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The IgM-Fc receptor (FcμR) is involved in IgM homeostasis as evidenced by increased pre-immune serum IgM and natural auto-antibodies of both IgM and IgG isotypes in Fcmr-deficient C57BL/6 (B6) mice. To determine the impact of Fcmr-ablation on autoimmunity, we introduced the Fcmr null mutation onto the Fas-deficient autoimmune-prone B6.MRL Fas (lpr/lpr) mouse background (B6/lpr). Both IgM and IgG auto-antibodies against dsDNA or chromatin appeared earlier in FcμR(-) B6/lpr than FcμR(+) B6/lpr mice, but this difference became less pronounced with age. Splenic B2 cells, which were 2-fold elevated in FcμR(+) B6/lpr mice, were reduced to normal B6 levels in FcμR(-) B6/lpr mice, whereas splenic B1 cells were comparable in both groups of B6/lpr mice. By contrast, marginal zone (MZ) B cells were markedly reduced in FcμR(-) B6/lpr mice compared with either FcμR(+) B6/lpr or wild type (WT) B6 mice. This reduction appeared to result from rapid differentiation of MZ B cells into plasma cells in the absence of FcμR, as IgM antibody to a Smith (Sm) antigen, to which MZ B cells are known to preferentially respond, was greatly increased in both groups (B6/lpr and B6) of FcμR(-) mice compared with FcμR(+) B6/lpr or B6 mice. Mott cells, aberrant plasma cells with intra-cytoplasmic inclusions, were also increased in the absence of FcμR. Despite these abnormalities, the severity of renal pathology and function and survival were all indistinguishable between FcμR(-) and FcμR(+) B6/lpr mice. Collectively, these findings suggest that FcμR plays important roles in the regulation of auto-antibody production, Mott cell formation and the differentiation of MZ B cells into plasma cells in B6.MRL Fas (lpr/lpr) mice.
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Affiliation(s)
- Kazuhito Honjo
- Department of Pathology, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - Yoshiki Kubagawa
- Department of Pathology, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - Yusuke Suzuki
- Department of Internal Medicine, Division of Nephrology, Juntendo University School of Medicine, Tokyo 113-8421, Japan
| | - Miyuki Takagi
- Department of Internal Medicine, Division of Nephrology, Juntendo University School of Medicine, Tokyo 113-8421, Japan
| | - Hiroshi Ohno
- Laboratory for Intestinal Ecosystem, RIKEN Center for Integrative Medical Sciences, Yokohama 230-0045, Japan
| | - R Pat Bucy
- Department of Pathology, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - Shozo Izui
- Department of Pathology and Immunology, University of Geneva, 1211 Geneva 4, Switzerland
| | - Hiromi Kubagawa
- Department of Pathology, University of Alabama at Birmingham, Birmingham, AL 35294, USA
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Chang SH, Kim TJ, Kim YJ, Liu Y, Min SY, Park MJ, Park HS, Lee SK, Nam KH, Kim HY, Mohan C, Kim HR. The lupus susceptibility locus Sle1 facilitates the peripheral development and selection of anti-DNA B cells through impaired receptor editing. THE JOURNAL OF IMMUNOLOGY 2014; 192:5579-85. [PMID: 24835399 DOI: 10.4049/jimmunol.1201558] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Systemic lupus erythematosus is characterized by the spontaneous production of IgG autoantibodies in patients and lupus-prone mice. In this study, we investigated the effect of the Sle1 lupus susceptibility locus on the peripheral development of 56R(+) anti-DNA transgenic B cells by tracking 56R(+) B cells in mice without (B6.56R) or with (B6.Sle1.56R) the Sle1 locus. Compared with B6.56R mice, B6.Sle1.56R mice exhibited increased class-switched IgG2a anti-DNA Abs in their serum, encoded by the transgene. Interestingly, within the spleen, Sle1 facilitated the development of these cells into clusters of IgG2a class-switched B cells juxtaposed to CD4(+) T cells within extrafollicular sites. Through sequence analysis of B cell hybridomas, we also found that B cells from B6.Sle1.56R mice are inefficient at Ig H and L chain editing. Thus, the Ig H chains in Sle1.56R(+) B cells are partnered more often with cationic L chains that facilitate DNA binding. Taken together, these findings indicate that the Sle1 lupus-susceptibility locus may facilitate the emergence of anti-DNA B cells by subduing BCR revision and possibly by shaping the extrafollicular development of effector B cells, although the precise molecular mechanisms await further study.
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Affiliation(s)
- Soog-Hee Chang
- Department of Anatomy and Biomedical Sciences, Seoul National University College of Medicine, Jongno-gu, Seoul 110-799, Republic of Korea; Department of Microbiology and Immunology, Seoul National University College of Medicine, Jongno-gu, Seoul 110-799, Republic of Korea; Division of Rheumatology, Department of Internal Medicine, School of Medicine, The Catholic University of Korea, Seocho-Gu, Seoul, 137-040, Republic of Korea
| | - Tae-Joo Kim
- Department of Anatomy and Biomedical Sciences, Seoul National University College of Medicine, Jongno-gu, Seoul 110-799, Republic of Korea; Department of Microbiology and Immunology, Seoul National University College of Medicine, Jongno-gu, Seoul 110-799, Republic of Korea; Division of Rheumatology, Department of Internal Medicine, School of Medicine, The Catholic University of Korea, Seocho-Gu, Seoul, 137-040, Republic of Korea
| | - Young-Joo Kim
- Department of Anatomy and Biomedical Sciences, Seoul National University College of Medicine, Jongno-gu, Seoul 110-799, Republic of Korea; Department of Microbiology and Immunology, Seoul National University College of Medicine, Jongno-gu, Seoul 110-799, Republic of Korea; Division of Rheumatology, Department of Internal Medicine, School of Medicine, The Catholic University of Korea, Seocho-Gu, Seoul, 137-040, Republic of Korea
| | - Yang Liu
- Division of Rheumatology, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX 75390; and
| | - So-Youn Min
- Division of Rheumatology, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX 75390; and
| | - Min-Jung Park
- Division of Rheumatology, Department of Internal Medicine, School of Medicine, The Catholic University of Korea, Seocho-Gu, Seoul, 137-040, Republic of Korea
| | - Hyun-Sil Park
- Division of Rheumatology, Department of Internal Medicine, School of Medicine, The Catholic University of Korea, Seocho-Gu, Seoul, 137-040, Republic of Korea
| | - Sun-Kyung Lee
- Department of Anatomy and Biomedical Sciences, Seoul National University College of Medicine, Jongno-gu, Seoul 110-799, Republic of Korea
| | - Ki-Hoan Nam
- Biomedical Mouse Resource Center, Korea Research Institute of Bioscience and Biotechnology, Ochang-eup, Cheongwon-gun, Chungbuk 363-883, Republic of Korea
| | - Ho-Youn Kim
- Division of Rheumatology, Department of Internal Medicine, School of Medicine, The Catholic University of Korea, Seocho-Gu, Seoul, 137-040, Republic of Korea;
| | - Chandra Mohan
- Division of Rheumatology, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX 75390; and
| | - Hang-Rae Kim
- Department of Anatomy and Biomedical Sciences, Seoul National University College of Medicine, Jongno-gu, Seoul 110-799, Republic of Korea;
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Liu C, Bai X, Wu J, Sharma S, Upadhyaya A, Dahlberg CIM, Westerberg LS, Snapper SB, Zhao X, Song W. N-wasp is essential for the negative regulation of B cell receptor signaling. PLoS Biol 2013; 11:e1001704. [PMID: 24223520 PMCID: PMC3818172 DOI: 10.1371/journal.pbio.1001704] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2013] [Accepted: 09/25/2013] [Indexed: 11/19/2022] Open
Abstract
Negative regulation of receptor signaling is essential for controlling cell activation and differentiation. In B-lymphocytes, the down-regulation of B-cell antigen receptor (BCR) signaling is critical for suppressing the activation of self-reactive B cells; however, the mechanism underlying the negative regulation of signaling remains elusive. Using genetically manipulated mouse models and total internal reflection fluorescence microscopy, we demonstrate that neuronal Wiskott-Aldrich syndrome protein (N-WASP), which is coexpressed with WASP in all immune cells, is a critical negative regulator of B-cell signaling. B-cell-specific N-WASP gene deletion causes enhanced and prolonged BCR signaling and elevated levels of autoantibodies in the mouse serum. The increased signaling in N-WASP knockout B cells is concurrent with increased accumulation of F-actin at the B-cell surface, enhanced B-cell spreading on the antigen-presenting membrane, delayed B-cell contraction, inhibition in the merger of signaling active BCR microclusters into signaling inactive central clusters, and a blockage of BCR internalization. Upon BCR activation, WASP is activated first, followed by N-WASP in mouse and human primary B cells. The activation of N-WASP is suppressed by Bruton's tyrosine kinase-induced WASP activation, and is restored by the activation of SH2 domain-containing inositol 5-phosphatase that inhibits WASP activation. Our results reveal a new mechanism for the negative regulation of BCR signaling and broadly suggest an actin-mediated mechanism for signaling down-regulation.
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MESH Headings
- Actins/metabolism
- Animals
- Antibodies, Antinuclear/blood
- Antigens/immunology
- Autoantibodies/blood
- B-Lymphocytes/immunology
- B-Lymphocytes/metabolism
- Cells, Cultured
- Humans
- Leukocytes, Mononuclear/immunology
- Leukocytes, Mononuclear/metabolism
- Mice
- Mice, 129 Strain
- Mice, Inbred C57BL
- Mice, Inbred CBA
- Mice, Knockout
- Protein Transport
- Receptors, Antigen, B-Cell/metabolism
- Signal Transduction
- Wiskott-Aldrich Syndrome/immunology
- Wiskott-Aldrich Syndrome/metabolism
- Wiskott-Aldrich Syndrome Protein/metabolism
- Wiskott-Aldrich Syndrome Protein, Neuronal/physiology
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Affiliation(s)
- Chaohong Liu
- Department of Cell Biology & Molecular Genetics, University of Maryland, College Park, Maryland, United States of America
| | - Xiaoming Bai
- Division of Immunology, Children's Hospital of Chongqing Medical University, Chongqing, China
| | - Junfeng Wu
- Division of Immunology, Children's Hospital of Chongqing Medical University, Chongqing, China
| | - Shruti Sharma
- Division of Infectious Diseases and Immunology, Department of Medicine, University of Massachusetts Medical School, Worcester, Massachusetts, United States of America
| | - Arpita Upadhyaya
- Department of Physics, University of Maryland, College Park, Maryland, United States of America
| | - Carin I. M. Dahlberg
- Translational Immunology Unit, Department of Medicine, Karolinska Institute, Stockholm, Sweden
| | - Lisa S. Westerberg
- Translational Immunology Unit, Department of Medicine, Karolinska Institute, Stockholm, Sweden
| | - Scott B. Snapper
- Department of Medicine, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Xiaodong Zhao
- Division of Immunology, Children's Hospital of Chongqing Medical University, Chongqing, China
| | - Wenxia Song
- Department of Cell Biology & Molecular Genetics, University of Maryland, College Park, Maryland, United States of America
- Division of Immunology, Children's Hospital of Chongqing Medical University, Chongqing, China
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Sato-Hayashizaki A, Ohtsuji M, Lin Q, Hou R, Ohtsuji N, Nishikawa K, Tsurui H, Sudo K, Ono M, Izui S, Shirai T, Takai T, Nishimura H, Hirose S. Presumptive role of 129 strain-derived Sle16 locus in rheumatoid arthritis in a new mouse model with Fcγ receptor type IIb-deficient C57BL/6 genetic background. ACTA ACUST UNITED AC 2013; 63:2930-8. [PMID: 21953083 DOI: 10.1002/art.30485] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
OBJECTIVE Fcγ receptor type IIb (FcγRIIb) is a major negative regulator of B cells, and the lack of FcγRIIb expression has been reported to induce systemic lupus erythematosus (SLE) in mice of the C57BL/6 (B6) genetic background. The 129 strain-derived Sle16 locus on the telomeric region of chromosome 1 including polymorphic Fcgr2b confers the predisposition to systemic autoimmunity when present on the B6 background. We undertook this study to examine the effect of the Sle16 locus on autoimmune disease in FcγRIIb-deficient B6 mice. METHODS We established 2 lines of FcγRIIb-deficient B6 congenic mouse strains (KO1 and KO2) by selective backcrossing of the originally constructed FcγRIIb-deficient mice on a hybrid (129×B6) background into a B6 background. Although both lack FcγRIIb expression, the KO1 and KO2 strains carry different lengths of the 129 strain-derived telomeric chromosome 1 segment flanked to the null-mutated Fcgr2b gene; the KO1 strain carries a 129 strain-derived ∼6.3-Mb interval distal from the null-mutated Fcgr2b gene within the Sle16 locus, while this interval in the KO2 strain is of B6 origin. RESULTS Unexpectedly, both strains failed to develop SLE; instead, the KO1 strain, but not the KO2 strain, spontaneously developed severe rheumatoid arthritis (RA) with an incidence reaching >90% at age 12 months. CONCLUSION The current study shows evidence that the epistatic interaction between the Fcgr2b-null mutation and a polymorphic gene(s) in the 129 strain-derived interval located in the distal Sle16 locus contributes to RA susceptibility in a new mouse model with the B6 genetic background, although the participation of other genetic polymorphisms cannot be totally excluded.
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Dutta M, Schwartzberg PL. Characterization of Ly108 in the thymus: evidence for distinct properties of a novel form of Ly108. THE JOURNAL OF IMMUNOLOGY 2012; 188:3031-41. [PMID: 22393150 DOI: 10.4049/jimmunol.1103226] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Ly108 (CD352) is a member of the signaling lymphocyte activation molecule (SLAM) family of receptors that signals through SLAM-associated protein (SAP), an SH2 domain protein that can function by the recruitment of Src family kinases or by competition with phosphatases. Ly108 is expressed on a variety of hematopoietic cells, with especially high levels on developing thymocytes. We find that Ly108 is constitutively tyrosine phosphorylated in murine thymi in a SAP- and Fyn kinase-dependent manner. Phosphorylation of Ly108 is rapidly lost after thymocyte disaggregation, suggesting dynamic contact-mediated regulation of Ly108. Similar to recent reports, we find at least three isoforms of Ly108 mRNA and protein in the thymus, which are differentially expressed in the thymi of C57BL/6 and 129S6 mice that express the lupus-resistant and lupus-prone haplotypes of Ly108, respectively. Notably, the recently described novel isoform Ly108-H1 is not expressed in mice having the lupus-prone haplotype of Ly108, but is expressed in C57BL/6 mice. We further provide evidence for differential phosphorylation of these isoforms; the novel Ly108-H1does not undergo tyrosine phosphorylation, suggesting that it functions as a decoy isoform that contributes to the reduced overall phosphorylation of Ly108 seen in C57BL/6 mice. Our study suggests that Ly108 is dynamically regulated in the thymus, shedding light on Ly108 isoform expression and phosphorylation.
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Affiliation(s)
- Mala Dutta
- Institute of Biomedical Sciences, The George Washington University, Washington, DC 20052, USA
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From genome-wide association studies to etiology: probing autoimmunity genes by RNAi. Trends Mol Med 2011; 17:634-40. [DOI: 10.1016/j.molmed.2011.06.006] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2011] [Revised: 06/08/2011] [Accepted: 06/13/2011] [Indexed: 11/20/2022]
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Marín-Vidalled MJ, Bolívar A, Zubiaga A, López-Hoyos M. The combined effect of BCL-2 over-expression and E2F2 deficiency induces an autoimmune syndrome in non-susceptible mouse strain C57BL/6. Autoimmunity 2010; 43:111-20. [PMID: 20187704 DOI: 10.3109/08916930903214033] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Multiple evidences support the notion that cell-cycle deregulation or apoptosis alterations can lead to autoimmune syndrome (AIS). Inactivation of the cell-cycle regulator E2F2 or over-expression of the anti-apoptotic Bcl-2 protein induces spontaneously an AIS in certain mouse strains. In the present study, we have examined the contribution of the genetic background on the development of autoimmunity after E2F2 gene inactivation, and the effect that a simultaneous inactivation of the E2F2 gene and over-expression of the Bcl-2 gene in B cells has on lymphoid homeostasis and autoimmunity. We show that E2F2(- / - ) mice carrying wild-type levels of Bcl-2 do not develop AIS when they are in a non-pro-autoimmune background (C57BL/6). However, mice harboring both genetic alterations concomitantly develop late AIS characterized by the presence of serum anti-nuclear antibodies, double and single strand anti-DNA antibodies, and the development of a mild glomerulonephritis with mesangial immunoglobulins, mainly IgA, deposits. These results suggest that alterations in cell-cycle and cell survival are critical contributing factors for the development of autoimmunity.
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