The goal of this proposal is to define mechanisms that regulate V(D)J recombination in the earliest B lymphocyte precursors. The continual production of B cells in the bone marrow (BM) is essential for the proper function of the immune system, and BM stromal cell factors are critical to support this production. The initiation of V(D)J recombination of immunoglobulin (Ig) genes is a limiting step in B cell development, and efficient recombination is required to generate the immense diversity of Igs needed to combat an ever expanding number of pathogens. V(D)J recombination is strictly regulated: in particular, expression of V(D)J recombinase components RAG1 and RAG2 is tightly controlled. We hypothesize that extrinsic signals from stromal cells such as the cytokine IL-7 regulate the recombinase in the earliest B progenitors through as yet undefined mechansisms.
Specific Aim 1 is to determine the mechanism by the IL7R:JAK3:pSTAT5 pathway regulates the V(D)J recombinase. We detected V(D)J recombinase activity in uncommitted common lymphoid progenitors (CLPs) but not in upstream progenitors. Therefore, we hypothesize that signals to the - CLP mediate critical control mechanisms for recombinase activity. We have demonstrated that the essential kinase in the IL-7 pathway, JAK3, is required for recombinase activity in CLPs. pSTATS is the transcription factor activated by JAK3, and therefore we will investigate the mechanisms by which STATS may regulate recombinase activity, including direct regulation of rag gene expression.
Specific Aim 2 is to define the specific role of the transcription factor E47 in the regulation of recombinase activity and investigate regulation of E47. We demonstrated that E47 KO mice lack recombinase activity in CLPs, and will now determine if this reflects direct regulation of expression of both ragl and rag2. Flt3 is the tyrosine kinase receptor for flt3- ligand;because both flt3- and E47-deficient mice have reduced numbers of CLPs, we will examine the role of flt3 in the regulation of E47 expression. >:.; Relevance to human health: IL-7, FL and their receptors are well-conserved between mice and humans.,., . Thus, findings using murine models should aid investigations aimed at generating new human lymphocytes for therapeutic purposes including transplantation, recovery from chemotherapy, gene therapy, curing , inherited and acquired immunodeficiencies, and promoting new B cell development in aging individuals.

National Institute of Health (NIH)
National Institute of Allergy and Infectious Diseases (NIAID)
Research Project (R01)
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Cellular and Molecular Immunology - B Study Section (CMIB)
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Nasseri, M Faraz
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University of Massachusetts Medical School Worcester
Schools of Medicine
United States
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Selimyan, Roza; Gerstein, Rachel M; Ivanova, Irina et al. (2013) Localized DNA demethylation at recombination intermediates during immunoglobulin heavy chain gene assembly. PLoS Biol 11:e1001475
Guikema, Jeroen E J; Gerstein, Rachel M; Linehan, Erin K et al. (2011) Apurinic/apyrimidinic endonuclease 2 is necessary for normal B cell development and recovery of lymphoid progenitors after chemotherapeutic challenge. J Immunol 186:1943-50
Priyadharshini, Bhavana; Welsh, Raymond M; Greiner, Dale L et al. (2010) Maturation-dependent licensing of naive T cells for rapid TNF production. PLoS One 5:e15038
Castro, Iris; Wright, Jacqueline A; Damdinsuren, Bazarragchaa et al. (2009) B cell receptor-mediated sustained c-Rel activation facilitates late transitional B cell survival through control of B cell activating factor receptor and NF-kappaB2. J Immunol 182:7729-37
Gerstein, Rachel M (2009) Deciding the decider: Mef2c in hematopoiesis. Nat Immunol 10:235-6
Coles, Andrew H; Marfella, Concetta G A; Imbalzano, Anthony N et al. (2008) p37Ing1b regulates B-cell proliferation and cooperates with p53 to suppress diffuse large B-cell lymphomagenesis. Cancer Res 68:8705-14
Pilbeam, Kristy; Basse, Per; Brossay, Laurent et al. (2008) The ontogeny and fate of NK cells marked by permanent DNA rearrangements. J Immunol 180:1432-41
Kuo, Ya-Huei; Gerstein, Rachel M; Castilla, Lucio H (2008) Cbfbeta-SMMHC impairs differentiation of common lymphoid progenitors and reveals an essential role for RUNX in early B-cell development. Blood 111:1543-51
Hoek, Kristen L; Antony, Pierre; Lowe, John et al. (2006) Transitional B cell fate is associated with developmental stage-specific regulation of diacylglycerol and calcium signaling upon B cell receptor engagement. J Immunol 177:5405-13
Borghesi, Lisa; Hsu, Lih-Yun; Miller, Juli P et al. (2004) B lineage-specific regulation of V(D)J recombinase activity is established in common lymphoid progenitors. J Exp Med 199:491-502

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