Leucocyte adhesion under flow conditions: principles important in tissue engineering

An understanding of inflammatory responses is important in a wide variety of tissue engineering applications. This review describes the current understanding of a central aspect of inflammatory responses, the adhesion of leucocytes to blood vessel walls prior to their emigration into tissues. These highly specific adhesive interactions are mediated by three main families of receptors: the selectins, integrins, and members of the immunoglobulin superfamily. Under flow conditions, the various receptors make distinct contributions to a multistep process of adhesion in which leucocytes roll, adhere firmly, and eventually transmigrate. Two examples in which these principles are important in tissue engineering research, lymphocyte adherence in transplant rejection and monocyte adherence in atherosclerosis, are discussed in the last part of the paper.