Lymphocyte Homing and Homeostasis

VA Palo Alto Health Care System, Palo Alto, California, United States
Science (Impact Factor: 33.61). 05/1996; 272(5258):60-6. DOI: 10.1126/science.272.5258.60
Source: PubMed


The integration and control of systemic immune responses depends on the regulated trafficking of lymphocytes. This lymphocyte
“homing” process disperses the immunologic repertoire, directs lymphocyte subsets to the specialized microenvironments that
control their differentiation and regulate their survival, and targets immune effector cells to sites of antigenic or microbial
invasion. Recent advances reveal that the exquisite specificity of lymphocyte homing is determined by combinatorial “decision
processes” involving multistep sequential engagement of adhesion and signaling receptors. These homing-related interactions
are seamlessly integrated into the overall interaction of the lymphocyte with its environment and participate directly in
the control of lymphocyte function, life-span, and population dynamics. In this article a review of the molecular basis of
lymphocyte homing is presented, and mechanisms by which homing physiology regulates the homeostasis of immunologic resources
are proposed.

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