Nahed Ismail, MD, PhD, D(ABMM), D(ABMLI)
Associate Professor of Pathology

Dr. Ismail is a member of the Division of Clinical Microbiology at UPMC and serves as Medical Director of the Clinical Microbiology Lab at Magee-Womens Hospital of UPMC. She is board-certified by the American Board of Medical Microbiology (ABMM) and American Board of Medical Laboratory Immunology (ABMLI). She serves as Chair-Elect for Division V (Clinical and Diagnostic Immunology) of the American Society of Microbiology.

Office Location:
Department of Pathology
S739 Scaife Hall
3550 Terrace Street
Pittsburgh, PA 15261
Contact Information:
Office Telephone: 412-648-8436
Lab Telephone: 412-648-8067
Fax: 412-648-9564


  • MD - Tanta University, Egypt, 1989
  • MSc - University of Toronto, 1996
  • PhD - University of Saskatchewan, 2000

Clinical Expertise

Dr. Ismail's expertise in the Division of Clinical Microbiology and Immunology at Magee-Womens Hospital is focused on providing laboratory tests to assist in detection of sexual transmitted diseases including molecular detection of Chlamydia trachomatis, Neisseria gonorrhoea, Trichomonas vaginalis, Human papilloma virus (HPV), Herpes simplex virus (HSV); diagnosis of group B streptococcus colonization in women of childbearing age, and serological diagnosis of HIV, hepatitis B and C viruses, and syphilis.

Research Expertise

Dr. Ismail has a long-standing interest in understanding the immune mechanisms involved in host defense against intracellular bacteria. Her research is focused on tick-borne infections caused by ehrlichiae and rickettsiae, which cause a number of different diseases including potentially fatal human monocytic ehrlichiosis (HME) and spotted fever group rickettsiosis (SFGR).

Using murine models of human monocytic ehrlichiosis, we have discovered that fatal disease is due to immunopathology mediated by natural killer (NK) cells and CD8 T cells. These findings were unexpected, because NK and CD8 T cells are known to normally contribute to protective immunity against infections with intracellular pathogens. Although clearance of ehrlichiae is mediated by CD4+T producing IFN-gamma, these cells undergo suppression and/or apoptosis during fatal disease.

In my lab, our current research aims to analyze the immune-pathogenic mechanisms that lead to fatal human ehrlichiosis. Current projects in the lab include:

  • determining how ehrlichiae activates NK and CD8 T cells
  • investigating the underlying mechanism of tissue injury mediated by NK and CD8 T cells
  • analyzing the role of macrophages and dendritic cells in activation and differentiation of protective CD4+Th1 cells
  • determining the contributions of cytokines and chemokines, as well as their corresponding receptors, to the pathogenesis of fatal ehrlichiosis.
Another area of research in Dr. Ismail's laboratory is focused on the characterization of the immunoregulatory mechanisms during spotted fever rickettsiosis. These studies are part of an ongoing collaboration with investigators at the University of Texas Medical Branch, Galveston, Texas. In particular, this research is aimed at understanding the role of dendritic cells and T regulatory cells (Tregs) in controlling the effector functions of antigen-specific CD4 T cells and CD8 T cells during innocuous and lethal infections in murine models of spotted fever rickettsiosis.

Several molecular and immunological technologies are utilized in Dr. Ismail's research. These include microarrays, serial analysis of gene expression, proteomic approaches, multi-parameter flow cytometry, radiation chimera, gene targeted knockout mice. In addition, the lab utilizes standard cell cultures, microbiologic, histopathologic, and confocal microscopy studies to determine mechanisms of diseases caused by these bacterial pathogens.

Studies outlined above will enable us to identify or evaluate novel host or microbial targets that can be used in the development of vaccine or immunotherapy against these important pathogens.


  • American Board of Medical Microbiology (ABMM)
  • American Board of Medical Laboratory Immunology (ABMLI)

Awards and Honors

Chair: Division V (Clinical and Diagnostic Immunology) of American Society for Microbiology

Selected Publications

View Dr. Ismail's publications on PubMed

Partho Chattoraj, Qin Yang, Ankita Khandai, Omar Al-Hendy, and Nahed Ismail. TLR2 and Nod2 mediate resistance or susceptibility to fatal intracellular Ehrlichia infection in murine models of ehrlichiosis. PLOS One, 8:e58514. 2013

Qin Yang, Purnima Ghose, Nahed Ismail. Neutrophils Suppress Protective Immunity and Mediate Immunopathology in Mice during Fatal Bacterial Infection-Induced Toxic Shock. Submitted to: Infect & Immun, 81:1751-63. 2013

Ismail, N., D. H. Walker, P. Ghose, and Yi-W. Tang. Immune Mediators of Protective and Pathogenic Immune Responses in Patients with Mild and Fatal Human Monocytotropic Ehrlichiosis. BMC Immunology, 13: 26, 2012

Ismail, N., and Shurin MR. Cancer and Infection: Friends or Foes. Future Oncology. 8: 1061-1064, 2012

Fang, R., N. Ismail, and D. H. Walker. NK cells contribute greatly to host innate resistance to murine spotted fever rickettsiosis. Am. J. Pathology, 181: 185-195, 2012

Ghose, P., A. Q. Ali, R. Fang, D. Forbes, B. Ballard, and N. Ismail. The interaction between IL-18 and IL-18R limits the magnitude of protective immunity and enhances pathogenic responses following infection with intracellular bacteria. J. Immunol. 187:1333-46. 2011

Valdes, P., N. R. Thirumalapura, N. Ismail, X-j, Yu, H. L. Stevenson, C. Pietzche, S. Thomas and D. H. Walker. Immunization with Ehrlichia outer membrane P28 proteins confers protection in a mouse model of ehrlichiosis. Clinical Vaccine Immunology. 18:2018-25, 2011

Ismail, H., M. Soliman, and N. Ismail. Occult Hepatitis B Virus Infection in Hemodialysis Egyptian Patients with or without Hepatitis C virus Infection. Open Access Pathology and Laboratory Medicine International, 2:113-120, 2010

Stevenson, H.L., Estes, D.M., Thirumalapura, R. N., Walker, D.H. and Ismail, N. Natural killer cells promote tissue Injury and systemic inflammatory responses during fatal Ehrlichia-induced toxic shock-like syndrome. American Journal of Pathology, 177: 766-776. 2010


Ismail, N. (2011). Pathogenesis of Ehrlichia and Anaplasma Infection and Disease. In Critical needs and gaps in understanding: prevention, amelioration, and resolution of lyme and other tick-borne diseases: The short-term and long-term outcomes. Workshop report, Institute of Medicine, National Academy of Science press, 114-118, 2011.

Stevenson, H. L., and N. Ismail. (2011). Innate Immune Response and Inflammation: Roles in Pathogenesis and Protection against Anaplasmataceae. ASM Text on Rickettsiales.

Ismail, N., K. C. Bloch, and J. W. McBride. (2010). Human Ehrlichiosis and Anaplasmosis. The Clinics in Laboratory Medicine, 30: 261-292.

McBride, J. W., J. Olano, and N. Ismail. (2010). Molecular diagnosis of Ehrlichia infection. Taylor & Francis Group (CRC Press), Molecular Detection of Human Bacterial Pathogens, Dongyou Liu.