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Photo of Dr. Sean Leng

Sean Xiao Leng, M.D., Ph.D.

Associate Professor of Medicine

Male  | Languages: English, Chinese

Appointment Phone


Main Location

Johns Hopkins Bayview Medical Center

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Call 410-464-6641 (8a.m. to 6p.m., EST, Mon-Fri)

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Call +1-410-502-7683 (7a.m. to 6p.m., EST, Mon-Fri)

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  • Associate Professor of Medicine

Centers & Institutes



Johns Hopkins Bayview Medical Center

Appointment Phone: 410-550-0925

5501 Hopkins Bayview Circle
Asthma and Allergy Center 5B.777
Baltimore, MD 21224 map
Phone: 410-550-2494
Fax: 410-550-3143


Geriatric Medicine

Research Interests

International collaborative development of geriatrics and aging research programs; Molecular virology: assessment of chronic cytomegalovirus infection and its contribution to chronic inflammation and immunosenescence in older adults; Immune response to and protection from influenza immunization in frail elderly; Cytokinology: IL-6 and other cytokine dysregulations in frail older adults; Chronic inflammation, immune activation, and their role in the pathogenesis of frailty; Aging of the innate and adaptive immune system


Dr. Sean X. Leng is an associate professor of medicine at the Johns Hopkins University School of Medicine. His areas of clinical expertise include geriatric medicine.

Dr. Leng earned his M.D. from Jiangxi Medical College and his Ph.D. from Texas A&M University Health Sciences Center. He completed his residency at Mount Sinai St. Luke's - Roosevelt Hospitals and performed a fellowship in geriatric medicine and gerontology at Johns Hopkins.

His research interests include international collaborative development of geriatrics and aging research programs.

In 2007 Dr. Leng received the Paul Beeson Career Development Award in Aging Research, one of the most prestigious in the field of geriatric research. more

    Additional Information

  • Education +


    • Jiangxi Medical College / MD (1984)


    • Mount Sinai St. Luke's - Roosevelt Hospitals / Medicine (2000)


    • Yale University School of Medicine (1997)
    • Johns Hopkins Bayview Medical Center / Geriatric Medicine and Gerontology (2002)


    • American Board of Internal Medicine / Geriatric Medicine (2002, 2012)
  • Research & Publications +

    Selected Publications

    Peer-reviewed publications:

    1. Leng X, and Ye ST. An investigation on in vivo allergenicity of Artemisia annua leaves and stems. Asian Pacific J. Allergy & Immunol. 1987; 5:125-27
    2. Leng X, and Ye ST. One year observation of immunotherapy for Artemisia hay fever in China: a clinical and immunological study. Asian Pacific J. Allergy Immunol. 1987;5:167-69
    3. Leng X, and Ye ST. Studies on the human basophil degranulation test with Artemisia pollen allergen. Chinese J. Microbiol. & Immunol. 1988; 8(2): 114-16
    4. Leng X and Ye ST. Allergenicity of non-pollen components of Artemisia Annua. Shanghai J. Immunol. 1988; 8(2):91-94
    5. Leng X, and Ye ST. Basophil degranulation in Artemisia pollinosis patients before and after specific immunotherapy. Chinese J. Microbiol. & Immunol. 1988 ; 8(3):185-87
    6. Leng X, Fu YX, Duan SQ, and Ye ST. A double-blind, placebo-controlled trial of oral immunotherapy for Artemisia pollen asthma with evaluation of bronchial response to the pollen allergen and serum specific IgE antibody. Ann. Allergy 1990; 64(1): 27-31
    7. Leng X and Wilson VG. Genetically defined NLS of BPV-1 E1 protein is necessary and sufficient for the nuclear localization of E1 fusion proteins. J. Gen. Virol. 1994; 75:2463-67
    8. Leng X, Ludes-Meyers JH, and Wilson VG. Isolation of an amino-terminal region of BPV-1 E1 protein that retains origin binding and E2 interaction capacity. J Virol. 1997;71(1):848-52
    9. Leng SX and Elias JE. Interleukin-11 inhibits macrophage interleukin-12 production. J. Immunol. 1997; 159:2161-68
    10. Leng SX and Elias JE. Interleukin-11. Int J Biochem Cell Biol. 1997; 29: 1059-1062
    11. Tang WL, Yang L, Leng SX, and Elias JE. TGF- stimulates IL-11 transcription via complex AP-1-dependent pathways. J Biol Chem. 1998; 273:5506-13
    12. Leng SX, Erim E, McShine E, Bloom PA, and Kotler DP. Influence of medical illness on body composition and quality of life in geriatric outpatients: a pilot study. J. Am. Geri. Soc. 2000; 48 (12):1737-38
    13. Leng SX, Chaves P, Koenig K, and Walston J. Serum IL-6 and hemoglobin as physiologic correlates in the geriatric syndrome of frailty. J. Am. Geri. Soc. 2002; 50:1268-1271
    14. Leng SX, Cappola A, Anderson R, Blackman M, Koenig K, Yang H, Blair M, and Walston J. Serum levels of IGF-1 and DHEA-S and their relationships with serum IL-6 in the geriatric syndrome of frailty. Aging Clin. Exp. Res. 2004; 16:153-57
    15. Leng SX, Yang H, and Walston J. Decreased cell proliferation and altered cytokine production in frail older adults. Aging Clin. Exp. Res. 2004; 16:249-52
    16. Leng SX, Xue Q, Huang Y, Semba R, Chaves P, Bandeen-Roche K, Fried L, and Walston J. Total and differential white blood cell counts and their associations with circulating IL-6 levels in community-dwelling older women. J. Gerontol. Med. Sci. 2005; 60A:195-199
    17. Semba R, Margolick J, Leng SX, Walston J, Ricks M, and Fried LP. T cell subsets and mortality in older community-dwelling women. Exp. Gerontol. 2005; 40:81-87
    18. Schmaltz H, Fried LP, Xue Q, Walston J, Leng SX, and Semba R. Chronic cytomegalovirus infection and inflammation are associated with prevalent frailty among community-dwelling older women. J. Am. Geri. Soc. 2005; 53:747-54
    19. Chaves P, Semba R, Leng SX, Woodman R, Ferrucci L, Guralnik J, and Fried L. Anemia, cardiovascular disease, and frailty in community-dwelling older women: The Womens Health and Aging Studies I and II. J Gerontol. Med. Sci. 2005; 60A: 729-35
    20. Leng SX, Xue Q, Huang Y, Ferrucci L, Fried L, and Walston J. Baseline total and specific differential white blood cell counts and 5-year all-cause mortality in community-dwelling older women. Exp Gerontol. 2005; 40:982-7
    21. Cappola A, Xue Q, Walston J, Leng S, Ferrucci L, Gruralnik J, and Fried L. DHEAS levels and mortality in disabled older women: WHAS I. J Gerontol. Med. Sci. 2006 Sep;61:957-62
    22. Leng SX, Xue Q, Tian J, Walston J, and Fried L. Inflammation and frailty in older women. J. Am. Geri. Soc. 2007; 55:864-71
    23. Leng SX, X-P Tian, S Durso, G Lazarus, C Lu, D Li, T Shen, and LP Fried. The aging population and development of geriatrics in China. J. Am. Geri. Soc. 2008; 56:571-3
    24. Walston J, Fedarko N, Yang H, Leng S, Beamer B, Espinoza S, Lipton A, Zheng H, and Becker K. The physical and biological characterization of a frail mouse model. J Gerontol. Med. Sci. 2008; 63:391-8
    25. De Fanis U, Wang G, Fedarko N, Walston J, Casolaro V, and Leng SX. T lymphocytes expressing chemokine receptor-5 and frailty in older adults. J. Am. Geri. Soc. 2008, 56(5):904-8. Epub 2008 April 1.
    26. Espinoza SE, Guo H, Fedarko N, DeZern D, Fried L, Xue Q, Leng S, Beamer B, and Walston J. Glutathione peroxidase enzyme activity in aging. J Gerontol. Med. Sci. 2008, 63:505-9
    27. Leng SX, JE McElhaney, NS Fedarko, and GA Kuchel. ELISA and multiplex technology for cytokine measurement in inflammation and aging research J Gerontol. Med. Sci. 2008, 63A:879-84.
    28. Qu T, Yang H, Walston J, Fedarko N, Beamer B, Ferrucci L, and Leng SX. Upregulation of stress-responsive inflammatory pathway genes by LPS-induced CD14+ monocytes in frail older adults. Mech Aging Dev. 2009, 130:161-166.
    29. Leng SX and LP Fried. Inflammatory markers and frailty, In: Fulop T, Franceschi C, Hirokawa K, Pawlec G Ed. Handbook on Immunosenescence: Basic Understanding and Clinical Applications. 2009 Springer, New York, Page; 1293-1303.
    30. Leng SX, Hung W, Cappola AR, Yu Q, Xue Q-L, and Fried LP. White Blood Cells Counts, Insulin-like Growth Factor-1 Levels, and Frailty in Community-Dwelling Older Women. J Gerontol. Med. Sci. 2009, 64A:499-502.
    31. Qu T, Yang H, Walston J, Fedarko N, and Leng SX. Monocytic expression of chemokine CXCL10 and its relationship with serum IL-6 levels in frailty. Cytokine 2009, 46:319-24 Epub 2009 April 1
    32. Fried LP, Xue QL, Cappola AR, Ferrucci L, Chaves P, Varadhan R, Guralnik JM, Leng SX, Semba RD, Walston JD, Blaum CS, and Bandeen-Roche K. Nonlinear, multisystem physiologic dysregulation associated with frailty in older women: implications for etiology and treatment. J Gerontol. Med. Sci. 2009, 64A:1049-57 Epub 2009 June 31
    33. Leng SX, Xue QL, Tian J, Huang Y, Yeh SH, and Fried LP. Associations of Neutrophil and Monocyte Counts with Frailty in Community-Dwelling Disabled Older Women: Results from the Womens Health and Aging Study I. Exp Gerontol. 2009, 44:511-516 Epub 2009 May 18
    34. Leng SX, Tian XP, Liu XH, Lazarus G, Bellantoni M, Greenough W, Fried LP, Shen T, and Durso SC. An international model for geriatrics program development in China: the Johns Hopkins Peking Union Medical College experience. J. Am. Geri. Soc. 2010; 58:1376-81.
    35. Spencer ME, Jain A, Matteini A, Beamer BA, Wang NY, Leng SX, Punjabi NM, Walston JD, and Fedarko NS. Serum levels of the immune activation marker neopterin change with age and gender and are modified by race, BMI and percentage body fat. J Gerontol. Med. Sci. 2010; 65:858-65. Epub 2010 May 17
    36. Xie HY, Leng S, Li DJ, and Shen T. PACE the new and effective medical service model for the elderly. Int. J Geriatr. 2010, 31:135-8.
    37. Yao X, Li H, and Leng SX. Immune system alterations in frailty. Clinics in Geriatric Medicine 2011; 27:79-87.
    38. Leng SX. American geriatrics: principles and novel care models. Chinese J. of Intern Med.2011; 31:31-33.
    39. Leng SX, Qu T, Semba RD, Li H, Yao X, Nilles T, Yang X, Manwani B, Walston JD, Ferrucci L, Fried LP, Margolick JB, Bream JH. Relationship between cytomegalovirus (CMV) IgG serology, detectable CMV DNA in peripheral monocytes, and CMV pp65(495-503)-specific CD8 (+) T cells in older adults. AGE (Dordr). 2011 Jan 28. [Epub ahead of print]
    40. Leng SX, Li HF, Xue QL, Tian J, Yang X, Ferrucci L, Fedarko N, Fried LP, and Semba RD. Association of detectable cytomegalovirus (CMV) DNA in monocytes rather than positive CMV IgG serology with elevated neopterin levels in community-dwelling older adults. Exp Gerontol 2011 April 13. [Epub ahead of print]
    41. Leng SX, Tian XP, Matteini A, Li HF, Hughes J, Jain A, Walston J, and Fedarko N. IL-6-independent association of elevated serum neopterin levels with prevalent frailty in community-dwelling older adults. Age Ageing 2011 May 17. [Epub ahead of print]
    42. Yao X, Hamilton RG, Weng NP, Xue QL, Bream JH, Li HF, Tian J, Yeh SH, Resnick B, Xu XY, Walston, J, Fried LP, and Leng SX. Frailty is associated with impairment of vaccine-induced antibody response and increase in post-vaccination influenza infection in community-dwelling older adults. Vaccine 2011 May 9. [Epub ahead of print]

    Selected abstracts:

    1. Leng SX. 2009. Immunobiology of Ageing. The International Congress of Gerontology and Geriatric Medicine (ICGGM), New Delhi, India (invited speaker)
    2. Leng SX. 2009. Role of inflammation in frailty. The ICGGM, New Delhi, India (invited speaker)
    3. Leng SX. 2009. Old age care in China. The ICGGM, New Delhi, India (invited speaker)
    4. Tian XP, Bogdanovic J, Resnick B, Xue QL, Hamilton R, and Leng SX. 2009. Influenza immunization in older adults over 70 years of age: how effective is it? American Geriatrics Society (AGS) annual meeting (Paper), Chicago, IL
    5. Qu T, Bogdanovic J, Resnick B, Xue QL, Hamilton R, Fried LP, and Leng SX. 2009. Antibody response to influenza immunization in frailty. AGS annual meeting (Presidential Poster), Chicago, IL
    6. Mehta A, Qu T, and Leng SX. 2009 Chemokine CXCL-10 expression and regulation by TGF- in vitro and its relevance to the pathogenesis of frailty. AGS annual meeting (poster), Chicago, IL
    7. Leng SX. 2009. (Symposium organizer): role of monocytes/macrophages in age-related immune decline, anemia, and frailty. Gerontological Society of America (GSA) Annual Scientific Meeting, Atlanta, GA
    8. Leng SX. 2009. Frailty is associated with impairment in vaccine-induced immune response in older adults. GSA Annual Scientific Meeting, Atlanta, GA (Symposium)
    9. Leng SX. 2010. Acute and chronic inflammation in the elderly: role in Acute Kidney Injury. Association of Specialty Professors (ASP) workshop on acute kidney injury in older adults co-sponsored by the AGS, American Society of Nephrology (ASN), NIA, and NIDDK. Arlington, VA (invited speaker)
    10. Abadir P, Koch LG, Li HF, Walston JD, Britton S, and Leng SX. 2010. Cytokine profiling for aged low capacity runner (LCR) rats: A Rat model for human frailty. GSA Annual Scientific Meeting, New Orleans, LA (Paper)
    11. Yao X, Qu, T, Semba RD, Yang X, Bream JH, J Margolick J, and Leng SX. 2010. Detectable Cytomegalovirus (CMV) DNA Predicts High CMV-Specific CD8+ T-Cells in HLA-A2+ Older Adults. GSA Annual Scientific Meeting, New Orleans, LA (Poster)
    12. Li HF, Koch L, Yang H, Manwani B, Walston J, Brittan S, and Leng SX. 2011. Low capacity runner (LCR) rat as a model for human obese frailty: physical and T-cell phenotypic characterization. AGS annual meeting, Washington, DC
    13. Zhu ML, Wang QM, Leng SX, and Liu XH. 2011. Attitude towards advanced care planning for the elderly in China AGS annual meeting, Washington, DC
    14. Asaad G, Li HF, Koch L, Manwani B, Yang H, Manwani B, Brittan S, and Leng SX. 2011. Rapamycin inhibition of TNF-alpha production by splenocytes in a rat model for obese frailty: Specific to T-cell stimulation. AGS annual meeting, Washington, DC
  • Academic Affiliations & Courses +
  • Activities & Honors +


    • Paul Beeson Career Development Award in Aging Research, 2007

    Professional Activities

    • Faculty Development Program, Johns Hopkins University, 2002 - 2003
    • Faculty leadership training, Johns Hopkins University School of Medicine, 2006 - 2007
    • Special Volunteer, National Institute on Aging, 2001 - 2002
      Gerontology Research Center
  • Videos & Media +
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