Specifically, Baird works with immunoglobulin E (IgE) antibodies, which mount membrane proteins on mast cells to form receptor complexes that sense the environment and sensitize the cell to allergens, which are substances that cause an allergic reaction. Typically, two or more receptors cluster together when they bind with an antigen (allergen or foreign body), and this causes transmembrane activation of enzymes within the cell that eventually lead to the release of histamines.
Such processes begin on the nanoscale (a nanometer equals one-billionth of a meter) -- at the molecular level on the cell's surface and lead to a system-wide response. At present, very little is known about the structural changes caused by receptor clustering that allow cells to sense their outer environment and start cellular processes within the cell.
The so-called nano-keys are surfaces of silicon with a layer of polymer or a thin lipid (fatty molecules that make up cell membranes) bilayer. The surfaces, which are engineered on the micron scale (0.000001 meter; there are 25,400 microns in an inch), are arranged in patterns that contain antigens and cause IgE-receptors to cluster when the cells attach to the surface. This activates the cell's inner machinery.
Said Baird: "In this way, we can control what the cell sees. The cells are binding to the engineered surfaces and getting turned on. We can then see how the cell is organizing itself due to the stimulus."
Collaborators include: David Holowka, Cornell senior scientist in chemistry; and the research groups of Harold G. Craighead, Cornell professor of applied and engineering physics; Dan Luo, Cornell assistant professor of biological and environmental engineering; Christopher Ober, Cornell professor of materials science and engineering; Watt Webb, Cornell's Eckert Pr
Source:Cornell University News Service