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Team / Chan

ChanJohn Chan MD

Professor, Department of Medicine (Infectious Diseases)
Professor, Department of Microbiology & Immunology
john.chan [at] einstein.yu.edu

My laboratory studies the interaction between the host and Mycobacterium tuberculosis, with the goals of understanding the lung immune response to the tubercle bacillus, deciphering the mechanisms by which this pathogen enters a latent state and subsequently reactivates, and developing novel effective anti-tuerculosis interventions including vaccines. The latency reactivation study seeks to understand how specific mycobacterial factors regulate bacterial growth and how specific host factors contain latent bacilli and modulate the immune response in chronic infection. We are examining the role of mycobacterial factors with growth-regulatory attribute in tuberculous persistence and reactivation. We are also studying mycobacterial factors that can regulate host cell TNF production; these components are being evaluated as vaccine targets. The host study has shown that B cells contribute to the development of optimal anti-tuberculous immunity and play an important role in regulating inflammation in tuberculous infection. We believe information gained from these studies can help guide the development of strategies that can better control tuberculosis.

Sushma-1Sushma Bharrhan, PhD

Research Fellow
sushma.bharrhan [at] einstein.yu.edu

My work is focused on the role of B cells in regulating the immune response to Mycobacterium tuberculosis (Mtb) infection. We know that B cells are a prominent part of the germinal center (GC)-like aggregates seen in the lungs of mice (and humans) infected with Mtb, but we don’t know what antigens these B cells recognize. A major goal of my work is to use a number of in vivo and in vitro systems to identify the antigen targets of the B cell response during tuberculosis infection and to characterize their role in TB immunity.


Siva-1Sivagami sundaram Chavadi, PhD

Research Fellow
siva.chavadi [at] einstein.yu.edu

Understanding host pathogen interaction is vital for developing better management strategies for infectious diseases. I work on the interface between microbial physiology and its effect on host immune responses. I am interested in elucidating the mechanisms underlying Mycobacterium tuberculosis (Mtb) latency and reactivation. Specifically, I am studying the role of an Mtb universal stress protein in the establishment of mycobacterial persistence. I am also working on how Mtb might exploit specific metabolic pathways to evade the host immune response in order to establish persistence. Knowledge gained from this work has the potential to be translated into anti-mycobacterial strategies, including developing novel drugs, improved vaccine strategies and diagnostics that could distinguish different stages of TB.

Yong-2Yong Chen, MD, PhD

Research Fellow
yong.chen [at] einstein.yu.edu

My focus is on developing an effective vaccine against Mycobacterium tuberculosis (Mtb), and understanding how the host immune system responds to Mtb infection in mouse model. The major projects are described as follows: I) To identify Mtb components that can regulate host cell tumor necrosis factor (TNF) production and to target these bacterial factors to enhance immunogenicity, therefore, generate a TNF-based effective tuberculosis (TB) vaccine. II) To evaluate how B cell and humoral immunity regulate immune response in Mtb infection, and to determine the requirement of B cells for the development of optimal vaccine efficacy upon immunization.

Simren-1Simren Mehta, Ph.D.

Research Fellow
simren.mehta [at] einstein.yu.edu

Previous work from our lab and others has shown that B cells are required for optimal protection against Mtb. Although B cells can have a number of different functions, preliminary evidence suggests their protective effect against Mtb may in part be mediated by antibody. I am utilizing mouse strains deficient in antibody isotypes to investigate the role of antibodies in promoting a protective immune response to Mtb. The knowledge gained from these studies will be utilized in designing better vaccines against Mtb.

Jiayong-2Jiayong Xu

Research Technician and BSL-3 In-charge
xu_jiayong [at] yahoo.com

My overall research goal is to understand how Mycobacterium tuberculosis interacts with the host. This interaction is critical in determining how the bacterium evades the host immune response and how the host controls tuberculosis infection. I help in setting up different murine experimental tuberculosis models in the lab. I am mainly responsible for the maintenance of the biosafety level 3 (BSL3) containment facility, the training of new researchers to work in the BSL3 environment, and for ordering supplies and equipment for the laboratory. Also, I participate in the design of protocols for experiments carried out in our lab, as well as in preparing data and figures for publication.


Patrick-1Patrick Bilder, PhD

Research Fellow

My research objective is to assist with the development of a live, attenuated Mycobacterium tuberculosis (Mtb) vaccine. Through the biochemical characterization of mycobacterial lipid and lipoglycan cell envelope moieties that mediate host inflammatory suppression, I aim to identify and characterize putative vaccine adjuvants and their associated immunoregulatory properties.


AaronAaron Olsen

Graduate Student

The success of the host against TB is dependent upon a proper cytokine response, including optimal expression of TNF. It is the goal of my research to identify mechanisms by which MtB components can effect production of host derived TNF. Through targeted deletion of these bacterial components, I am trying to identify a more immunogenic strain, with the eventual goal of developing a safe and effective TB vaccine.