William J. Janssen
Associate Professor
Department of Medicine
Division of Pulmonary, Critical Care and Sleep Medicine
  • 5280 Top Doctors 2016
  • Recognized as a 5280 Top Doctor
  • America’s Top Doctors 2015 — Castle Connolly, Medical, Ltd.
  • Recognized in America’s Top Doctors — Castle Connolly, Inc.
  • Best Doctors in America® 2015 — Best Doctors, Inc.
  • Recognized in Best Doctors in America® — Best Doctors, Inc.
  • America’s Top Doctors 2016 — Castle Connolly Medical, Ltd.
  • Special Interests

    Clinical Interests

    My clinical interests are in critical care medicine and chronic obstructive pulmonary disease. I also specialize in the treatment of septic shock, acute lung injury, and ARDS (acute respiratory distress syndrome).


    Research Interests

    My research is focused on mechanisms of repair following acute and chronic lung injury. This includes studying how lung collectins influence alveolar macrophage phenotype, function, and fate in healthy lungs and during inflammation. I am also interested in the role that bone-marrow-derived stem cells (including endothelial progenitor cells) play in recovery from lung injury.


    The Ohio State University, MD
    The Ohio State University, BS, Mechanical Engineering
    The Ohio State University, Internal Medicine
    University of Colorado Denver, Pulmonary and Critical Care

    Awards & Recognition

    2014: Best Doctors in America, Best Doctors, Inc.

    Board Certification

    Internal Medicine,
    Pulmonary Medicine,
    Critical Care

    Professional Memberships

    American Thoracic Society
    Society of Critical Care Medicine
    American College of Chest Physicians


    Sareli AE, Janssen WJ, Sterman D, Saint S, Pyeritz RF. What’s the connection? New Eng J. Med. 2008; 358(6):626-32.

    Ezzie E, Janssen WJ, O’Brien, JM, Fox C, Schwarz MI. Failure to respond, New Eng J Med. 2008; 358(1):70-4.

    Linderman DL, Janssen WJ. Critical care medicine for the hospitalist. Med Clin N. America 2008;92:467–479.

    Janssen WJ, McPhillips KA, Dickinson MG, Derek J. Linderman DJ, Morimoto K, Xiao YQ, Oldham KM, Vandivier RW,Henson PM, Gardai SJ.Surfactant Proteins A and D Tonically Suppress Alveolar Macrophage Phagocytosis via Interaction with SIRP?. Am J Respir Cell Crit Care Med. 2008;178)2):158-67

    McPhillips K, Janssen WJ, Ghosh M, Byrne A, Gardai SJ, Remigio L, Bratton DL, Kang JL, Henson PM. TNFa inhibits macrophage clearance of apoptotic cells via cPLA2 and oxidant-dependent mechanisms. J Immunol. 2007;178(12):8117-2612.

    Hospital Affiliations

    • Colorado Acute Long Term Hospital
    • Exempla Lutheran Medical Center
    • Rose Medical Center
    • Sky Ridge Medical Center
    • St. Joseph Hospital - Denver
    • Swedish Medical Center
    • University of Colorado Hospital

    Academic Affiliations

    Assistant Professor of Medicine, University of Colorado Denver

    Contact Information

    • Office: 877.225.5654
    • Email: janssenw@njhealth.org



    • National Jewish Health Main Campus
      1400 Jackson St.
      Denver, CO 80206

    • Saint Joseph Hospital
      1835 Franklin Street Denver, CO 80218

    Patient Ratings

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