Biomarker Discovery

Biomarker discovery has grown out of my labs focus on developing affordable proteomics techniques that resulted in two well-researched methods to allow any lab to identify novel protein interactions affected by their compound of interest. Our biomarker discovery work is focused on two areas, chronic low-level lead toxicity and manganese toxicity.

Low level, chronic toxicities are very difficult to identify and a systematic method of identifying individuals who are exposed and need further clinical attention needs to be established, further increased lead exposure tends to occur in areas lacking economic or social advantages. Humans are exquisitely sensitive to the presence of lead and one method of identifying individuals who are exposed to a toxicant is to use the organism’s biological responses as an indicator of exposure. In this sense the exposed individuals gene and protein expression patterns would serve as a harbinger of exposure. Quantifiable biological changes in gene and protein expression that are indicative of exposure or diseases are biomarkers. Biomarkers are important for the diagnosis of exposures that do not immediately leave a clinically quantifiable measure of an individual’s exposure. Low-level lead toxicity is one of these conditions.

Our approach utilizes carefully designed laboratory exercises (crowdsourcing) allowing more complete coverage, and built in experimental replication, while engaging undergraduate and graduate students in discovery learning.


Since 2003 Dr. Gillespie has worked as a curator/editor on the Reactome project at a multinational effort distributed between Ontario Institute for Cancer Research/Cold Spring Harbor Laboratory, European Bioinformatics Institute, Gene Ontology Consortium, and New York University. Reactome is an online bioinformatics database of human biology described in molecular terms. It is an on-line encyclopedia of core human pathways – DNA replication, transcription, translation, the cell cycle, metabolism, and signaling cascades – and can be browsed to retrieve up-to-date information about a topic of interest, e.g., the molecular details of the signaling cascade set off when the hormone insulin binds to its cell-surface receptor, or used as an analytical tool for the interpretation of large datasets like those generated by DNA microarray analysis. The information in Reactome is provided by expert biologists and gathered from the published research literature. Each module is peer-reviewed before it is publicly released on the Reactome website, and is periodically updated.

SNARE Proteins & Immunology

Uncovering or identifying novel mast cell targets that mediate disease or disease progression may lead to the development of novel therapeutics for the treatment of allergy/asthma and autoimmune disease. Mast cells are granulocytes that  differentiatefrom myeloid progenitors in the bone marrow and play a critical role in innate immunity as vital sentinel cells that combat invading microorganisms through the release of a plethora of inflammatory mediators. However, dysregulation of mast cell function can lead to allergic and autoimmune disease, which affect more than 80 million people in the United States alone. The transport and fusion of inflammatory mediator-laden vesicles to the membrane in granulocytes and their subsequent exocytosis has been postulated to be mediated by a family of evolutionarily-conserved proteins known as the SNAREs (soluble N-ethylmaleimide-sensitive factor attachment protein receptors). The expression and functional role(s) of two SNARE family members SNAP-25 and SNAP-23 in mast cell degranulation has not been fully elucidated. We are using pharmacological methods and RNA interference methods (siRNA oligos to SNAP-25 and SNAP-23) and gene overexpression studies (with SNAP-25 and/or SNAP-23) to fully examine the role of both proteins in FceRI receptor-activated or Ca2+ionophore-activate rat RBL-2H3 mast cells. These studies are identifying novel protein partners and complexes; all new targets for the treatment of allergic and autoimmune diseases.