Lehn Weaver, MD, PhD

Lehn Weaver, MD, PhD is an attending physician in the Center for Childhood Arthritis and Rheumatic Diseases at The Children's Hospital of Philadelphia.

Locations: Main Campus
Appointments and Referrals: 1-800-TRY-CHOP (1-800-879-2467)

  • Background

    With a consistent history of academic and clinical excellence, I have developed the ambition, knowledge, and drive to pursue an academic career in pediatric rheumatology. My intrigue for unraveling the intricacies of the innate immune system has led to my fascination with bringing new therapies for the prevention, treatment, and cure of pediatric rheumatic diseases.

    I have developed a model system to examine the inflammatory cues required for the initiation of systemic inflammation in the laboratory of Dr. Edward Behrens at The Children’s Hospital of Philadelphia. This research has led me to unravel how cell-intrinsic regulatory mechanisms thought to control myeloid cell responses are bypassed by inflammation-driven myelopoiesis, which generates an entourage of new effector cells capable of sustaining and enhancing subsequent inflammatory responses.

    As inflammation-induced myelopoiesis has been observed in other models of chronic inflammation and in patients with rheumatic diseases, it is intriguing to speculate whether the enhanced production of myeloid cells during systemic inflammatory responses is important for the subsequent development of frank autoimmunity. As this novel and therapeutically interesting idea is ripe for study, I plan to build upon my exciting findings by investigating the cellular and molecular mechanisms driving enhanced myelopoiesis during systemic inflammatory responses and expanding the scope of my preliminary data to the study myelopoiesis in two rheumatologically relevant diseases, arthritis and lupus.

    The results of this work will inform future attempts at rational, targeted therapeutic interventions for pediatric rheumatic diseases, as well as determine fundamental regulatory mechanisms that initiate and perpetuate chronic inflammation and autoimmunity. This is of particular interest in the pediatric population I treat where there may be an early window for intervention to reverse and/or cure rheumatic diseases if we develop a better understanding of early disease pathogenesis. In addition to pursuing my research interests, I will continue to treat patients with musculoskeletal, inflammatory, and/or rheumatic diseases in our Pediatric Rheumatology Clinic.

  • Education and Training

    Medical School

    MD - Dartmouth Medical School, Hanover, NH

    Residency

    Pediatrics - The Children's Hospital of Philadelphia, Philadelphia PA

    Fellowship

    Pediatric Rheumatology - The Children's Hospital of Philadelphia, Philadelphia PA

    Board Certification

    Pediatric Advanced Life Support (PALS)

    Graduate Degree

    PhD in Immunology - Dartmouth College, Hanover, NH

  • Titles and Academic Titles

    Attending Physician

    Instructor, Perelman School of Medicine at the University of Pennsylvania

  • Departments and Services
  • Publications

    Papers

    2015

    Minoia F, Davì S, Horne A, Bovis F, Demirkaya E, Akikusa J, Ayaz NA, Al-Mayouf S, Barone P, Bica B, Bolt I, Breda L, De Cunto C, Enciso S, Gallizzi R, Griffin T, Hennon T, Horneff G, Jeng M, Kapovic AM, Lipton JM, Magni-Manzoni S, Rumba I, Magalhaes CS, Sewairi WM, Stine KC, Vougiouka O, Weaver LK, Davidsone Z, De Inocencio J, Ioseliani M, Lattanzi B, Tezer H, Buoncompagni A, Picco P, Ruperto N, Martini A, Cron RQ, and Ravelli A. (2014). Dissecting the heterogeneity of macrophage activation syndrome complicating systemic juvenile idiopathic arthritis. The Journal of Rheumatology.

    2014

    Weaver LK, Behrens EM. (2014). Hyperinflammation, rather than hemophagocytosis, is the common link between Macrophage Activation Syndrome and Hemophagocytic Lymphohistiocytosis. Current Opinion Rheumatology. 26(5):562-9.

    2013

    Costa-Reis P, Weaver LK, Behrens EM, Sullivan KE. (2013). Chronic Recurrent Multifocal Osteomyelitis in a Patient with Common Variable Immunodeficiency. Joint Bone Spine. 81(2):193-194.

    Weaver LK, Behrens EM. (2013). How to use… antinuclear antibodies in paediatric rheumatic diseases. Archives of Disease in Childhood. 98:64-70.

    Posters and Presentations

    2015

    Weaver LK and Behrens EM. (2015). Enhanced Myelopoiesis Downstream of Toll-Like Receptor 9 Activation Drives a Feed-Forward Inflammatory Response. 2015 ACR/ARHP Annual Meeting. San Francisco, CA.

    Biswas C, Weaver LK, and Behrens EM. (2015). Antibiotics alter TLR9 responses in vivo. 2015 PENN/CHOP Microbiome Symposium. Philadelphia, PA.

    Biswas C, Weaver LK, and Behrens EM. (2015). Antibiotics alter TLR9 responses in vivo. IgG Retreat. Harbourtowne, MD.

    Weaver LK and Behrens EM. (2015). Enhanced Myelopoiesis Downstream of Toll-Like Receptor 9 Activation Drives a Feed-Forward Inflammatory Response. IgG Retreat. Harbourtowne, MD.

    Weaver LK and Behrens EM. (2015). Extramedullary Myelopoiesis Drives Persistent Toll-like Receptor-Mediated Inflammation. CHOP Poster Day. Philadelphia, PA.

    2014

    Minoia F, Davì S, Horne A, Bovis F, Demirkaya E, Akikusa J, Ayaz NA, Al-Mayouf S, Barone P, Bica B, Bolt I, Breda L, De Cunto C, Enciso S, Gallizzi R, Griffin T, Hennon T, Horneff G, Jeng M, Kapovic AM, Lipton JM, Magni-Manzoni S, Rumba I, Magalhaes CS, Sewairi WM, Stine KC, Vougiouka O, Weaver LK, Davidsone Z, De Inocencio J, Ioseliani M, Lattanzi B, Tezer H, Buoncompagni A, Picco P, Ruperto N, Martini A, Cron RQ, and Ravelli A. (2014). Dissecting the Heterogeneity of Macrophage Activation Syndrome. 2014 ACR/ARHP Annual Meeting. Boston, MA.

    Weaver LK and Behrens EM. (2014). Extramedullary Myelopoiesis Drives Persistent Toll-like Receptor-Mediated Inflammation. ACR/ARHP Annual Meeting. Boston, MA.

    Minoia F, Davì S, Horne A, Bovis F, Demirkaya E, Akikusa J, Ayaz NA, Al-Mayouf S, Barone P, Bica B, Bolt I, Breda L, De Cunto C, Enciso S, Gallizzi R, Griffin T, Hennon T, Horneff G, Jeng M, Kapovic AM, Lipton JM, Magni-Manzoni S, Rumba I, Magalhaes CS, Sewairi WM, Stine KC, Vougiouka O, Weaver LK, Davidsone Z, De Inocencio J, Ioseliani M, Lattanzi B, Tezer H, Buoncompagni A, Picco P, Ruperto N, Martini A, Cron RQ, and Ravelli A. (2014). Dissecting the Heterogeneity of Macrophage Activation Syndrome. 21st European Pediatric Rheumatology Congress. Belgrade, Serbia.

    Weaver LK and Behrens EM. (2014). CCR2+ Inflammatory Monocytes Bypass Toll-like Receptor 9 Tolerance during CpG-Induced Inflammation. Gordon Research Conference. Mount Snow, VT.

    Burnham S, Behrens EM, Weiss P, Sherry DD, Lerman M, Knight A, Weaver LK, Taxter A, Ramsay E, Basaiga M, James K, Wiater L, Bieniakowski D, Peyton T, Lindsay M, Battle T, Taylor A, and Tanzer L. (2014). Improving methotrexate toxicity screening in juvenile idiopathic arthritis. CHOP Safety Day. Philadelphia, PA.

    Weaver LK and Behrens EM. (2014). A158: CpG-Induced Macrophage Activation Syndrome Develops Through an Organism Level Resistance to Toll-like Receptor 9 Tolerance. Arthritis Rheumatol. 66(suppl 11:S204). PRYSM Basic Science Poster Session. Orlando, FL.

    Weaver LK and Behrens EM. (2014). CpG-Induced Inflammation Develops Through an Organism Level Resistance to Toll-like Receptor 9 Tolerance. CHOP Poster Day. Philadelphia, PA.

    2013

    Weaver LK and Behrens EM. (2013). Innate Immune Cell Production of Interleukin-12 Drives CpG-Induced Macrophage Activation Syndrome. ACR/ARHP Annual Meeting. San Diego, CA.

    Weaver LK and Behrens EM. (2013). Hematopoietic Cells are Necessary and Sufficient to Drive CpG-Induced Macrophage Activation Syndrome. 23rd Annual CHOP Research Poster Day. Philadelphia, PA.

  • Awards and Honors

    2015, CHOP Research Poster Day Award
    2015, Rheumatology Research Foundation Scientist Development Award
    2014, ACR Pediatric Research Award
    2014, Best Basic Science Abstract by a Fellow-in-Training, PRYSM 2014
    2014, PRYSM Fellow-in-Training Travel Award
    2012-2013, Amgen/Pfizer Rheumatology Fellowship Training Award
    2011, American College of Rheumatology Fellow-in-Training Scholarship
    2010, The Children's Hospital of Philadelphia Travel Award for the ACR Meeting
    2009, American College of Rheumatology Resident Award
    2009, Thomas Almy DMS Chapter of the Gold Humanism in Medicine Honor Society
    2009, New Hampshire Pediatric Society Award
    2006, Munck-Pfefferkorn Student Fellow, Dartmouth Medical School
    2005, Travel Award, Society for Leukocyte Biology: Phagocytes in Innate Immunity
    2005, SRC Poster Award, FASEB Summer Research Conference on Autoimmunity
    2002, Presidential Fellow and University Scholar
    2002, Beta Beta Beta National Biology Society
    2000-2002, Barry Goldwater National Science Scholarship
    2000, Organic Chemist of the Year, Susquehanna University
    1998-2002, University Honors Program
    1997, Participant in the Pennsylvania Governor’s School for Health Care

  • Editorial and Academic Positions

    Ad-Hoc Reviewer

    2011-present Journal of Leukocyte Biology
    2011-present Pediatric Rheumatology On-line Journal
    2015-present International Immunopharmacology

  • Leaderships

    Memberships in Professional Organizations

    2013-present, The Federation of Clinical Immunology Societies
    2011-present, American College of Rheumatology