Person:
North, Trista

Profile Picture

Email Address

AA Acceptance Date

Birth Date

Research Projects

Organizational Units

Job Title

Last Name

North

First Name

Trista

Name

North, Trista
Author's Publications: search.filters.isAuthorOfPublication.e2cc2025-57da-43da-b6df-5605153477ed

Search Results

Now showing 1 - 9 of 9
  • Thumbnail Image
    Publication
    Developmental Vitamin D Availability Impacts Hematopoietic Stem Cell Production
    (2017) Cortes, Mauricio; Chen, Michael J.; Stachura, David L.; Liu, Sarah Y.; Kwan, Wanda; Wright, Francis; Vo, Linda T.; Theodore, Lindsay; Esain, Virginie; Frost, Isaura M.; Schlaeger, Thorsten M.; Goessling, Wolfram; Daley, George; North, Trista
    SUMMARY Vitamin D insufficiency is a worldwide epidemic affecting billions of individuals, including pregnant women and children. Despite its high incidence, the impact of active vitamin D3 (1,25(OH)D3) on embryonic development beyond osteo-regulation remains largely undefined. Here, we demonstrate that 1,25(OH)D3 availability modulates zebrafish hematopoietic stem and progenitor cell (HSPC) production. Loss of Cyp27b1-mediated biosynthesis or vitamin D receptor (VDR) function by gene knockdown resulted in significantly reduced runx1 expression and Flk1+cMyb+ HSPC numbers. Selective modulation in vivo and in vitro in zebrafish indicated that vitamin D3 acts directly on HSPCs, independent of calcium regulation, to increase proliferation. Notably, ex vivo treatment of human HSPCs with 1,25(OH)D3 also enhanced hematopoietic colony numbers, illustrating conservation across species. Finally, gene expression and epistasis analysis indicated that CXCL8 (IL-8) was a functional target of vitamin D3-mediated HSPC regulation. Together, these findings highlight the relevance of developmental 1,25(OH)D3 availability for definitive hematopoiesis and suggest potential therapeutic utility in HSPC expansion.
  • Thumbnail Image
    Publication
    Reconstruction of complex single-cell trajectories using CellRouter
    (Nature Publishing Group UK, 2018) Lummertz da Rocha, Edroaldo; Rowe, R. Grant; Lundin, Vanessa; Malleshaiah, Mohan; Jha, Deepak; Rambo, Carlos R.; Li, Hu; North, Trista; Collins, James; Daley, George
    A better understanding of the cell-fate transitions that occur in complex cellular ecosystems in normal development and disease could inform cell engineering efforts and lead to improved therapies. However, a major challenge is to simultaneously identify new cell states, and their transitions, to elucidate the gene expression dynamics governing cell-type diversification. Here, we present CellRouter, a multifaceted single-cell analysis platform that identifies complex cell-state transition trajectories by using flow networks to explore the subpopulation structure of multi-dimensional, single-cell omics data. We demonstrate its versatility by applying CellRouter to single-cell RNA sequencing data sets to reconstruct cell-state transition trajectories during hematopoietic stem and progenitor cell (HSPC) differentiation to the erythroid, myeloid and lymphoid lineages, as well as during re-specification of cell identity by cellular reprogramming of monocytes and B-cells to HSPCs. CellRouter opens previously undescribed paths for in-depth characterization of complex cellular ecosystems and establishment of enhanced cell engineering approaches.
  • Thumbnail Image
    Publication
    Teleost Growth Factor Independence (Gfi) Genes Differentially Regulate Successive Waves of Hematopoiesis
    (Elsevier BV, 2013) Cooney, Jeffrey D.; Hildick-Smith, Gordon J.; Shafizadeh, Ebrahim; McBride, Paul F.; Carroll, Kelli Jane; Anderson, Heidi; Shaw, George C.; Tamplin, Owen J.; Branco, Diana S.; Dalton, Arthur J.; Shah, Dhvanit I; Wong, Clara; Gallagher, Patrick G.; Zon, Leonard; North, Trista; Paw, Barry Htin
    Growth Factor Independence (Gfi) transcription factors play essential roles in hematopoiesis, differentially activating and repressing transcriptional programs required for hematopoietic stem/progenitor cell (HSPC) development and lineage specification. In mammals, Gfi1a regulates hematopoietic stem cells (HSC), myeloid and lymphoid populations, while its paralog, Gfi1b, regulates HSC, megakaryocyte and erythroid development. In zebrafish, gfi1aa is essential for primitive hematopoiesis; however, little is known about the role of gfi1aa in definitive hematopoiesis or about additional gfi factors in zebrafish. Here, we report the isolation and characterization of an additional hematopoietic gfi factor, gfi1b. We show that gfi1aa and gfi1b are expressed in the primitive and definitive sites of hematopoiesis in zebrafish. Our functional analyses demonstrate that gfi1aa and gfi1b have distinct roles in regulating primitive and definitive hematopoietic progenitors, respectively. Loss of gfi1aa silences markers of early primitive progenitors, scl and gata1. Conversely, loss of gfi1b silences runx-1, c-myb, ikaros and cd41, indicating that gfi1b is required for definitive hematopoiesis. We determine the epistatic relationships between the gfi factors and key hematopoietic transcription factors, demonstrating that gfi1aa and gfi1b join lmo2, scl, runx-1 and c-myb as critical regulators of teleost HSPC. Our studies establish a comparative paradigm for the regulation of hematopoietic lineages by gfi transcription factors.
  • Thumbnail Image
    Publication
    Identification of small molecules for human hepatocyte expansion and iPS differentiation
    (2013) Shan, Jing; Schwartz, Robert E.; Ross, Nathan T.; Logan, David J.; Thomas, David; Duncan, Stephen A.; North, Trista; Goessling, Wolfram; Carpenter, Anne E.; Bhatia, Sangeeta
    Cell-based therapies hold the potential to alleviate the growing burden of liver diseases. Such therapies require human hepatocytes, which, within the stromal context of the liver, are capable of many rounds of replication. However, this ability is lost ex vivo and human hepatocyte sourcing has been limiting many fields of research for decades. Here, we developed a high-throughput screening platform for primary human hepatocytes to identify small molecules in two different classes that can be used to generate renewable sources of functional human hepatocytes. One class induced functional proliferation of primary human hepatocytes in vitro. The second class enhanced hepatocyte functions and promoted differentiation of iPS-derived hepatocytes, toward a phenotype more mature than what was previously obtainable. The identification of these small molecules can help to address a major challenge impacting many facets of liver research and may lead to the development of novel therapeutics for liver diseases.
  • Thumbnail Image
    Publication
    The Wnt/β-Catenin Pathway Is Required for the Development of Leukemia Stem Cells in AML
    (American Association for the Advancement of Science (AAAS), 2010) Wang, Yingzi; Krivtsov, Andrei; Sinha, Amit U.; North, Trista; Goessling, Wolfram; Feng, Zhaohui; Zon, Leonard; Armstrong, Scott
    Leukemia stem cells (LSCs) are capable of limitless self-renewal and are responsible for the maintenance of leukemia. Because selective eradication of LSCs could offer substantial therapeutic benefit, there is interest in identifying the signaling pathways that control their development. We studied LSCs in mouse models of acute myelogenous leukemia (AML) induced either by coexpression of the Hoxa9 and Meis1a oncogenes or by the fusion oncoprotein MLL-AF9. We show that the Wnt/β-catenin signaling pathway is required for self-renewal of LSCs that are derived from either hematopoietic stem cells (HSC) or more differentiated granulocyte-macrophage progenitors (GMP). Because the Wnt/β-catenin pathway is normally active in HSCs but not in GMP, these results suggest that reactivation of β-catenin signaling is required for the transformation of progenitor cells by certain oncogenes. β-catenin is not absolutely required for self-renewal of adult HSCs; thus, targeting the Wnt/β-catenin pathway may represent a new therapeutic opportunity in AML.
  • Thumbnail Image
    Publication
    Prostaglandin E2 Enhances Human Cord Blood Stem Cell Xenotransplants and Shows Long-Term Safety in Preclinical Nonhuman Primate Transplant Models
    (Elsevier BV, 2011) Goessling, Wolfram; Allen, Robyn S.; Guan, Xiao; Jin, Ping; Uchida, Naoya; Dovey, Michael; Harris, James M.; Metzger, Mark E.; Bonifacino, Aylin C.; Stroncek, David; Stegner, Joseph; Armant, Myriam; Schlaeger, Thorsten; Tisdale, John F.; Zon, Leonard; Donahue, Robert E.; North, Trista
    Hematopoietic stem cells (HSCs) are used in transplantation therapy to reconstitute the hematopoietic system. Human cord blood (hCB) transplantation has emerged as an attractive alternative treatment option when traditional HSC sources are unavailable, however, the absolute number of hCB HSCs transplanted is significantly lower than bone marrow or mobilized peripheral blood stem cells (MPBSCs). We previously demonstrated that dimethyl-prostaglandin E2 (dmPGE2) increased HSCs in vertebrate models. Here, we describe preclinical analyses of the therapeutic potential of dmPGE2-treatment using human and non-human primate HSCs. dmPGE2 significantly increased total human hematopoietic colony formation in vitro and enhanced engraftment of unfractionated and CD34+ hCB following xenotransplantation. In non-human primate autologous transplantation, dmPGE2-treated CD34+ MPBSCs showed stable multilineage engraftment over one year post-infusion. Together, our analyses indicated that dmPGE2 mediates conserved responses in HSCs from human and non-human primates, and provided sufficient preclinical information to support proceeding to an FDA-approved phase 1 clinical trial.
  • Thumbnail Image
    Publication
    Distinct Roles for Matrix Metalloproteinases 2 and 9 in Embryonic Hematopoietic Stem Cell Emergence, Migration, and Niche Colonization
    (Elsevier, 2017) Theodore, Lindsay; Hagedorn, Elliott; Cortes, Mauricio; Natsuhara, Kelsey; Liu, Sarah Y.; Perlin, Julie; Yang, Song; Daily, Madeleine L.; Zon, Leonard; North, Trista
    Summary Hematopoietic stem/progenitor cells (HSPCs) are formed during ontogeny from hemogenic endothelium in the ventral wall of the dorsal aorta (VDA). Critically, the cellular mechanism(s) allowing HSPC egress and migration to secondary niches are incompletely understood. Matrix metalloproteinases (MMPs) are inflammation-responsive proteins that regulate extracellular matrix (ECM) remodeling, cellular interactions, and signaling. Here, inhibition of vascular-associated Mmp2 function caused accumulation of fibronectin-rich ECM, retention of runx1/cmyb+ HSPCs in the VDA, and delayed caudal hematopoietic tissue (CHT) colonization; these defects were absent in fibronectin mutants, indicating that Mmp2 facilitates endothelial-to-hematopoietic transition via ECM remodeling. In contrast, Mmp9 was dispensable for HSPC budding, being instead required for proper colonization of secondary niches. Significantly, these migration defects were mimicked by overexpression and blocked by knockdown of C-X-C motif chemokine-12 (cxcl12), suggesting that Mmp9 controls CHT homeostasis through chemokine regulation. Our findings indicate Mmp2 and Mmp9 play distinct but complementary roles in developmental HSPC production and migration.
  • Thumbnail Image
    Publication
    Single-cell transcriptional analysis of normal, aberrant, and malignant hematopoiesis in zebrafish
    (The Rockefeller University Press, 2016) Moore, Finola E.; Garcia, Elaine; Lobbardi, Riadh; Jain, Esha; Tang, Qin; Moore, John C.; Cortes, Mauricio; Molodtsov, Aleksey; Kasheta, Melissa; Luo, Christina C.; Garcia, Amaris J.; Mylvaganam, Ravi; Yoder, Jeffrey A.; Blackburn, Jessica S.; Sadreyev, Ruslan; Ceol, Craig J.; North, Trista; Langenau, David
    Hematopoiesis culminates in the production of functionally heterogeneous blood cell types. In zebrafish, the lack of cell surface antibodies has compelled researchers to use fluorescent transgenic reporter lines to label specific blood cell fractions. However, these approaches are limited by the availability of transgenic lines and fluorescent protein combinations that can be distinguished. Here, we have transcriptionally profiled single hematopoietic cells from zebrafish to define erythroid, myeloid, B, and T cell lineages. We also used our approach to identify hematopoietic stem and progenitor cells and a novel NK-lysin 4+ cell type, representing a putative cytotoxic T/NK cell. Our platform also quantified hematopoietic defects in rag2E450fs mutant fish and showed that these fish have reduced T cells with a subsequent expansion of NK-lysin 4+ cells and myeloid cells. These data suggest compensatory regulation of the innate immune system in rag2E450fs mutant zebrafish. Finally, analysis of Myc-induced T cell acute lymphoblastic leukemia showed that cells are arrested at the CD4+/CD8+ cortical thymocyte stage and that a subset of leukemia cells inappropriately reexpress stem cell genes, including bmi1 and cmyb. In total, our experiments provide new tools and biological insights into single-cell heterogeneity found in zebrafish blood and leukemia.
  • Thumbnail Image
    Publication
    SCF\(^{β-TRCP}\) Suppresses Angiogenesis and Thyroid Cancer Cell Migration by Promoting Ubiquitination and Destruction of VEGF Receptor 2
    (The Rockefeller University Press, 2012) Shaik, Shavali; Nucera, Carmelo; Inuzuka, Hiroyuki; Gao, Daming; Garnaas, Maija; Frechette, Gregory Martin; Harris, Lauren; Wan, Lixin; Fukushima, Hidefumi; Husain, Amjad; Nose, Vania; Fadda, Guido; Sadow, Peter; Goessling, Wolfram; North, Trista; Lawler, Jack; Wei, Wenyi
    The incidence of human papillary thyroid cancer (PTC) is increasing and an aggressive subtype of this disease is resistant to treatment with vascular endothelial growth factor receptor 2 (VEGFR2) inhibitor. VEGFR2 promotes angiogenesis by triggering endothelial cell proliferation and migration. However, the molecular mechanisms governing VEGFR2 stability in vivo remain unknown. Additionally, whether VEGFR2 influences PTC cell migration is not clear. We show that the ubiquitin E3 ligase SCF\(^{β-TRCP}\) promotes ubiquitination and destruction of VEGFR2 in a casein kinase I (CKI)–dependent manner. β-TRCP knockdown or CKI inhibition causes accumulation of VEGFR2, resulting in increased activity of signaling pathways downstream of VEGFR2. β-TRCP–depleted endothelial cells exhibit enhanced migration and angiogenesis in vitro. Furthermore, β-TRCP knockdown increased angiogenesis and vessel branching in zebrafish. Importantly, we found an inverse correlation between β-TRCP protein levels and angiogenesis in PTC. We also show that β-TRCP inhibits cell migration and decreases sensitivity to the VEGFR2 inhibitor sorafenib in poorly differentiated PTC cells. These results provide a new biomarker that may aid a rational use of tyrosine kinase inhibitors to treat refractory PTC.