The biology of chemokines and their receptors

During the last five years, the development of bioinformatics and EST datab ases has been primarily responsible for the identification of many new chem okines and chemokine receptors. The chemokine field has also received consi derable attention since chemokine receptors were found to act as co-recepto rs for HIV infection (1). In addition, chemokines, along with adhesion mole cules, are crucial during inflammatory responses for a timely recruitment o f specific leukocyte subpopulations to sites of tissue damage. However, che mokines and their receptors are also important in dendritic cell maturation (2), B (3), and T (4) cell development, Th1 and Th2 responses, infections, angiogenesis, and tumor growth as well as metastasis (5). Furthermore, an increase in the number of chemokine/receptor transgenic and knock-out mice has helped to define the functions of chemokines in vivo. In this review we discuss some of the chemokines' biological effects in vivo and in vitro, d escribed in the last few years, and the implications of these findings when considering chemokine receptors as therapeutic targets.