Developmental Biology

Basic Science Research

Mission Statement:

Directed by Wellington V. Cardoso, MD, PhD, the Lung Developmental Biology Program at the Boston University Pulmonary Center focuses on the study of developmental mechanisms from specification of lung progenitors and the emergence of the lung primordium to perinatal events that result in formation of the airways and alveoli. The Program congregates a highly interactive group of investigators with accumulated knowledge in lung morphogenesis and stem cell biology. The overall research goals are to elucidate the properties and fates of progenitor cells of the developing lung, to develop tools for their characterization, to understand how cell fate and morphogenesis are coupled and the genetic and epigenetic mechanisms that control these processes. There is increasing evidence of the involvement of developmental signals in disease conditions, such as pulmonary fibrosis and lung cancer. Our studies provide insights into the molecular mechanisms associated with aberrant responses of the lung in injury-repair processes and help understanding potential regenerative capacities of the lung.

Background:

Work on molecular aspects of lung development begun at the Pulmonary Center in 1991 by a group of investigators which has been continuously funded by a Program Project Grant from the National Heart, Lung, and Blood Institute (NHLBI) throughout 2012. In addition, the investigators have been supported by several NHLBI RO1s.from the Parker B. Francis Foundation and other sources. The group meets weekly to discuss research in progress, review recent literature and attend seminars from invited speakers. The group’s research is supported by several shared facilities within the Pulmonary Center and the medical campus. These include a core microscopy and image analysis, with access to confocal and laser capture microscopy and FACS, a gene microarray and bioinformatics facilities, and a mouse genetics core.

Current areas of investigation:

Genetic and epigenetic regulation of early lung development:

The mechanisms responsible for the acquisition of lung cell fate and lung bud initiation from the foregut endoderm are still elusive. To identify candidate regulators of these events we are characterizing global patterns of gene expression in the developing foregut prior to and at the onset of lung development. These studies led to the identification of significant changes in chromatin remodeling and DNA methylation genes at the onset of lung development, which are currently being investigated as putative regulators of early lung development. Moreover, we are studying common mechanisms of chromatin remodeling, DNA methylation and transcriptional regulation in lung development that might be activated in lung diseases, such as pulmonary fibrosis. We are identifying by chIP-on-chip analyses direct targets of the key lung transcription factor Nkx2-1 to characterize transcriptional regulatory networks in the lung development and its effect in tumorigenesis (Ramirez Lab).

We are also investigating the role of specific pathways, such as retinoic acid (RA) in formation of the lung primordium. By using genetic and pharmacological models of RA deficiency in global gene screenings, we have identified a gene network controlled by RA critical for formation of the primordial lung bud. Ongoing functional analysis shows that this network involves RA control of the Tgf beta pathway and ultimately expression of Fgf10, with the participation of Wnt signaling (Cardoso Lab).

Analysis of lung lineage specification using embryonic stem (ES) cells and induced pluripotent (iPS) stem cells

We are employing ES cells or iPS stem cells to model in vitro early lung developmental milestones and learn about signaling cascades required for lung specification (Kotton Lab). We use a variety of culture conditions and genetic manipulation techniques to study the mechanisms that control the differentiation of pluripotent or multipotent cells towards specified endodermal or lung epithelial cell lineages. Ultimately these findings are correlated with in vivo embryonic development in the mouse embryo. In collaboration with other laboratories in the Pulmonary Center (Ramirez Lab) and medical campus (Mostoslavsky Lab http://www.mostoslavskylab.com/), we are primarily focused on the roles of FGF and Wnt signaling pathways as well as epigenetic changes in early lung lineage specification. This research program interacts extensively with the campus-wide Boston University Center for Regenerative Medicine (CReM) www.bumc.bu.edu/stemcells.

Control of lung epithelial morphogenesis by microRNAs

MicroRNAs are small regulatory RNAs that modulate gene expression by translational suppression and degradation of their target mRNAs. There is increasing evidence that miRNAs play a major role in the regulation of developmental processes. One of the ongoing projects focuses on the characterization and function of specific miRNAs and their targets in the developing lung during branching morphogenesis. We are currently studying miRNAs that are involved in cell cycle regulation, fibrogenesis of mesenchymal cells, and in Shh or Tgfb signaling pathways in early lung development. We are also working on the functional analysis of the TNRC6 gene family members in lung development by using genetic modified mouse model. (Lu Lab)

Notch control of progenitor cell fate in the airway epithelium:

Airways are lined by a mixture of ciliated, secretory and neuroendocrine cells. We are investigating how lung progenitors give rise to these different cell types during development and how these fates are balanced during lung repair. We are particularly interested in the role of Notch signaling, which we found to be critical for formation of secretory Clara cells and to control ciliated cell differentiation. These studies provide insights into the mechanisms that regulate normal development, as well as the aberrant epithelial differentiation in conditions, such as asthma and chronic obstructive pulmonary disease (COPD) (Cardoso Lab).

Pulmonary vascular maturation

We are focused on the events that underlie maturation of the pulmonary artery in late mouse gestation, just prior to birth. This line of investigation includes identification of the smooth muscle progenitor cells and the signals that control their fate. One key signal that we have identified is Notcstrong (Fine Lab).

Mechanisms of expansion and patterning of progenitor cells in the developing lung

Little is known about how respiratory progenitors are expanded and patterned into proximal and distal compartments during formation of the lung primordium and initiation of branching. Our studies implicate signaling by Fgf10 and Notch in these events. We have identified novel targets of Fgf10 in the developing lung (Lu Lab, Cardoso Lab). We have recently shown that disruption of Notch signaling dramatically expands the population of distal lung progenitors, altering morphogenetic boundaries and proximal-distal lung patterning. We are further exploring the role of Notch-Jagged-Delta signaling using a combination of mouse genetic models and organ explant cultures. As an extension of these studies, we are assessing Notch-mediated mechanisms of cell fate choice in models of lung injury. (Cardoso Lab)

Acquisition of alveolar type I cell gene expression and flattening

We are interested in studying the molecular mechanisms that underlie flattening of lung alveolar epithelial type I cells during development using in vitro and in vivo models of normal and altered lung epithelial morphogenesis. We are testing the role of genes that regulate cell shape, polarization and cytoskeleton remodeling in type I cell morphogenesis ( Ramirez Lab)

Innervation of the pulmonary tract in development and diseases

Little is known about the neurogenesis in the pulmonary tract and its physiological function. We are investigating the origin of neurons in the trachea and lungs and the signals essential for the establishment of neural innervation. The potential crosstalk between neural and smooth muscle cells and its involvement in pulmonary diseases is also being studied (Ai Lab).

Development of the lung innate immunity

We are investigating the interactions between the developing lung and the developing hematopoietic system. These interactions are necessary for establishing a local and functional innate immune system prior to birth. We hope to elucidate how the embryonic lung locally controls differentiation of myeloid progenitors that we found to be localized to the fetal lung mesenchyme. We are also pursuing studies that will determine how certain distinct classes of hematopoietic cells regulate development of the lung’s arterial system in utero (Fine Lab).

Members of the Lung Developmental Biology Group:

  • Wellington V. Cardoso, MD, PhD, Professor of Medicine
  • Alan Fine, MD, Professor of Medicine
  • Maria I. Ramirez, PhD, Associate Professor of Medicine
  • Jining Lü, PhD, Assistant Professor of Medicine
  • Darrell Kotton, MD, Associate Professor of Medicine
  • Xingbin Ai, PhD, Assistant Professor of Medicine
  • Andrew Wilson, MD, Assistant Professor of Medicine
  • YuXia Cao, MD, Assistant Professor of Medicine
  • Felicia Chen, MD, Assistant Professor of Medicine
  • Gustavo Mostoslavsky, MD, PhD, Assistant Professor of Medicine

Postdoctoral Fellows:

  • Jean Bosco Tagne, PhD
  • Christine O’Brien, MD
  • Laertis Ikonomou, PhD
  • Arjun Guha, PhD
  • Yixin Tang, PhD
  • Shamik Ghosh, Ph.D.
  • Jesus Paez-Cortez, MD
  • Aba Somers, MD
  • Zhihua Jiang, PhD
  • Saaket Varma, PhD
  • Thanh Tran, PhD
  • Cesar A. Sommer PhD

Graduate Students:

  • Junjie Wu
  • Michelle Vasconcelos
  • Leah Cushing
  • Tyler Longmire
  • Constantina Christodoulou
  • Chris Ford
  • Dolly Thomas

Research Assistants

  • Jun Qian
  • Anne Hinds
  • Letty Kwok
  • Fei Radiagan
  • Sarah Ohle
  • Dan Dwyer
  • Kelsi Radzikinas
  • Fengzhi Shao
  • Ning Zhang
  • Tiffany Vo
  • Meenakshi Lakshminarayanan
  • Amel Omari
  • Aliete Langsdorf
  • Andreia Gianotti Sommer PhD

Representative publications:

  1. Tsao PN, Vasconcelos M, Izvolsky KI, Qian J, Lu J, Cardoso WV. Notch signaling controls the balance of ciliated and secretory cell fates in developing airways. Development 136: 2297-2307, 2009.
  2. Fine, A. Breathing Life into the Lung Stem Cell Field. Cell Stem Cell 4:468-469, 2009</li.
  3. Tsao PN, Chen F, Izvolsky KI, Walker J, Kukuruzinska MA, Lu J, Cardoso WV. Gamma-secretase activation of notch signaling regulates the balance of proximal and distal fates in progenitor cells of the developing lung. J. Biol. Chem. 283:29532-29544, 2008.
  4. Sommer CA, Stadtfeld M, Murphy GJ, Hochedlinger K, Kotton DN, Mostoslavsky G. “iPS Cell Generation Using a Single Lentiviral Stem Cell Cassette.” Stem Cells. Dec 18, 2008 [Epub ahead of print].
  5. Wilson AA, Kwok LW, Hovav AH, Ohle SJ, Little FF, Fine A, Kotton DN. “Sustained Expression of alpha1-antitrypsin After Transplantation of Manipulated Hematopoietic Stem Cells”. Am J Respir Cell Mol Biol. 39(2):133-41. Aug 2008.
  6. Millien, G., Beane, J., Lenburg, M., Tsao, P., Lu, J., Spira, A., Ramirez, M.I. (2008) Characterization of the mid-foregut transcriptome identifies genes regulated during lung bud induction. Gene Expression Patterns 8(2):124-139.
  7. Chen F., Desai T., Qian J., Niederreither K., Lu J, and Cardoso WV. Inhibition of Tgf beta signaling by endogenous retinoic acid is essential for primary lung bud induction. Development 134: 2969-2979, 2007.
  8. Izvolsky KI, Lu J, Martin G, Albrecht K, and Cardoso WV. Systemic inactivation of Hs6st1 in mice is associated with late postnatal mortality without major defects in organogenesis. Genesis 46:8-18, 2008.
  9. Lü J, Qian J, Keppler D, Cardoso WV . Cathespin H is an FGF10 Target Involved in BMP4 Degradation during Mouse Lung Branching Morphogenesis J. Biol Chem 282:22176–22184, 2007.
  10. Cardoso, WV and Lu, J. Regulation of early lung development: questions, facts and controversies. Development 133: 1161-1624, 2006.
  11. Desai T, Chen F., Lu J, Qian J, Niederreither K., Dollé, P., Chambon, P., and Cardoso WV. Distinct roles for retinoic acid receptors alpha and beta in early lung morphogenesis. Dev. Biol., 291:12-24, 2006.
  12. Mammoto, A., Connor, K.M., Mammoto, T., Yung, C. W., Huh, D., Aderman, C.H., Mostoslavsky, G., Smith, L.E.H. and Ingber, D.E. A mechanosensitive transcriptional mechanism that controls angiogenesis. 2009. Nature. Doi:10.1038. 457:1103-1108.
  13. Lü J, Qian J, Tang X, Li C, Chen F, Cardoso, WV. Differential expression of components of the microRNA machinery during mouse organogenesis. Biochem. Biophys. Research Com. 334:319-323, 2005.
  14. Jean JC, Lü J, Joyce-Brady M, Cardoso WV. Regulation of Fgf10 gene expression in murine mesenchymal cells. J. Cell Biochem., 103:1886-1894, 2008.
  15. Pogach M.S., Cao, Y., Millien, G., Ramirez, M.I., Williams, M.C. (2007) Key developmental regulators change during hyperoxia-induced injury and recovery in adult mouse lung. J. Cell. Biochem. 100(6):1415-29.
  16. Kathuria, H., Cao, Y.X., Hinds, M.I., Ramirez, M.I. , Williams, M.C. (2007) The ETS protein ERM regulates caveolin-1 transcription in mouse lung epithelial, but not endothelial cell lines. J Cell Biochem. 102(1):13-27.
  17. Millien, G., Spira, A., Hinds, A., Wang, J., Williams, M.C., Ramirez, M.I. (2006) Alterations in gene expression in T1alpha null lung: a model of deficient alveolar sac development. BMC Dev. Biol. 6(1):3
  18. Castro, M., Ramirez, M.I., Gern, J.E., Cutting, G., Redding, G., Hagood, J.S., Whitsett, J., Abman, S., Raj, J.U., Barst, R., Kato, G.J., Gozal, D., Haddad, G.G., Prabhakar, N.R., Gauda, E., Martinez, F.D., Tepper, R., Wood, R.E., Accurso, F., Teague, W.G., Venegas, J., Cole, F.S., Wright, R.J. (2009) Strategic Plan for Pediatric Respiratory Diseases Research: an NHLBI Working Group Report. Proc. Am. Thorac. Soc. 6:1-10.
  19. Murphy, J., Summer, R., Wilson , A.A., Kotton, D.N., and Fine, A . The Prolonged Life-Span of Alveolar Macrophages. American. Journal Respiratory. Cell Molecular Biology 38 : 380-385, 2008.
  20. Summer, R., Fitzsimmons K., Murphy, J, and Fine, A. Isolation and Characterization of an Adult Lung Mesenchymal Progenitor Cell. Am J Respir Cell Mol Biol. 37:152-9, 2007.
  21. Cardoso WV, Kotton DN. Specification and patterning of the respiratory system. (February 20, 2006), StemBook, ed. The Stem Cell Research Community, StemBook, doi/10.3824/stembook.1.10.1 http://www.stembook.org. 2008
  22. Summer, R., Little, F.F., Ouchi, N., Takemura, Y., Aprahamian, T., Dwyer, D., Fitzsimmons, K.. Suki, B., Parameswaran, H., Fine, A., Walsh, K. Alveolar macrophage activation and an emphysema-like phenotype in adiponectin-deficient mice. American Journal Physiology Lung Cell Molecular Physiology 294: L1035-L1042, 2008
  23. Murphy GJ, Mostoslavsky G, Kotton DN, and Mulligan RC. “Exogenous Control of Mammalian Gene Expression via Modification of Translational Termination.” Nature Medicine 12(9):1093-9. Sept 2006.
  24. Kotton DN, Fabian AJ, Mulligan RC. “Failure of Bone Marrow to Reconstitute Lung Epithelium.” Am J Respir Cell Mol Biol. 33:328-334. Oct 2005.
  25. Kotton DN, Fabian AJ, Mulligan RC. “A novel stem cell population in adult liver with potent hematopoietic reconstitution activity.” Blood. 106:1574-1580. Sept 2005.
  26. Mostoslavsky G, Kotton DN, Fabian AJ, Grey JT, Mulligan RC. “Efficiency of transduction of highly purified hematopoietic stem cells by lentiviral and retroviral vectors under conditions of minimal in vitro manipulation.” Molecular Therapy 11(6):932-40. June 2005
  27. Ai X, Kitazawa T, Do AT, Kusche-Gullberg M, Labosky PA, Emerson CP Jr. SULF1 and SULF2 regulate heparan sulfate-mediated GDNF signaling for esophageal innervation. Development . 2007;134(18):3327-38.
  28. Lansdoff A., Do A.T., Kusche-Gullberg M., Emerson C.P. Jr., and Ai X. (corresponding author) (2007) “Sulfs are regulators of growth factor signaling for satellite cell differentiation and muscle regeneration” Developmental Biology 311: 464-77