In our laboratory we study the mechanical properties of cells and the mechanochemistry of cell adhesion. We are particularly interested in learning about the molecular mechanisms underlying the control of cell deformability and cell adhesion, and the role that mechanical forces and membrane stability play in both the formation and separation of adhesive contacts. Our fundamental approach is to perform mechanical measurements on individual cells or cell pairs to measure response of cells to applied forces or the probability of cell adhesion under controlled conditions. Our main focus is the study of cells in the peripheral vasculature. The deformability of circulating cells and adhesive interactions between cells in the vasculature has relevance to diverse aspects of human physiology ranging from oxygen delivery and hemolytic anemia, to atherosclerosis or immune response and inflammation. Historically, our lab has been one of the leading facilities for investigating red blood cell mechanical properties and the stability of biological membranes. More recently we have begun to examine the physical mechanisms underlying neutrophil adhesion to endothelium, a key event in the body's response to infection or injury. Another area of interest is in the late stage maturation of red blood cells. We have observed changes in the mechanical properties that occur as red cells develop and mature. We are working on developing methods to observe the maturation of red cells in culture so that we can follow the maturation process in the laboratory. By correlating changes in mechanical stability with the appearance and assembly of cytoskeletal proteins we can deduce which molecules and what interactions are important for developing proper mechanical function. Maintaining mechanical stability appears to be critical for the successful completion of red blood cell maturation, as it appears that instabilities in the cell surface lead to loss of cell membrane and cell death if the membranes are not properly supported mechanically as they mature.