A novel xenograft model to study the role of TSLP-induced CRLF2 signals in normal and malignant human B lymphopoiesis

作者：Francis, Olivia L.; Milford, Terry-Ann M.; Martinez, Shannalee R.; Baez, Ineavely; Coats, Jacqueline S.; Mayagoitia, Karina; Concepcion, Katherine R.; Ginelli, Elizabeth; Beldiman, Cornelia; Benitez, Abigail; Weldon, Abby J.; Arogyaswamy, Keshav; Shiraz, Parveen; Fisher, Ross; Morris, Christopher L.; Zhang, Xiao-Bing; Filippov, Valeri; Van Handel, Ben; Ge, Zheng; Song, Chunhua; Dovat, Sinisa; Su, Ruijun Jeanna; Payne, Kimberly J.^*

来源：Haematologica-The Hematology Journal, 2016, 101(4): 417-426.

DOI：10.3324/haematol.2015.125336

• THYMIC STROMAL LYMPHOPOIETIN
• ACUTE LYMPHOBLASTIC-LEUKEMIA
• MOLECULAR-CLONING
• GENE-EXPRESSION
• PROGENITOR
• MURINE
• RECEPTOR
• STAT5
• REARRANGEMENT
• PROLIFERATION

Thymic stromal lymphopoietin (TSLP) stimulates in vitro proliferation of human fetal B-cell precursors. However, its in vivo role during normal human B lymphopoiesis is unknown. Genetic alterations that cause overexpression of its receptor component, cytokine receptor-like factor 2 (CRLF2), lead to high-risk B-cell acute lymphoblastic leukemia implicating this signaling pathway in leukemogenesis. We show that mouse thymic stromal lymphopoietin does not stimulate the downstream pathways (JAK/STAT5 and PI3K/AKT/mTOR) activated by the human cytokine in primary high-risk leukemia with overexpression of the receptor component. Thus, the utility of classic patient-derived xenografts for in vivo studies of this pathway is limited. We engineered xenograft mice to produce human thymic stromal lymphopoietin (+T mice) by injection with stromal cells transduced to express the cytokine. Control (-T) mice were produced using stroma transduced with control vector. Normal levels of human thymic stromal lymphopoietin were achieved in sera of +T mice, but were undetectable in -T mice. Patient-derived xenografts generated from +T as compared to -T mice showed a 3-6-fold increase in normal human B-cell precursors that was maintained through later stages of B-cell development. Gene expression profiles in high-risk B-cell acute lymphoblastic leukemia expanded in +T mice indicate increased mTOR pathway activation and are more similar to the original patient sample than those from -T mice. +T/-T xenografts provide a novel pre-clinical model for understanding this pathway in B lymphopoiesis and identifying treatments for high-risk B-cell acute lymphoblastic leukemia with overexpression of cytokine-like factor receptor 2.

• 出版日期2016-4
• 单位南京医科大学