ABSTRACT
Monocyte chemoattractant proteins-1 (MCP-1)was one of the first C-C chemokines identified and has since been studied extensively. One of the most popular approaches in investigating receptor usage is the concept of receptor desensitization. In this approach, cells are first challenged by one chemokine and the effects on the cells are measured. RANTES has been shown to be the most potent chemoattractant for eosinophils in vitro with activities equivalent to or higher then classical chemoattractants like C5a while MlP-1α has weaker effects. A novel C-C chemokine has been purified from lung lavages of allergen-challenged guinea pigs model that has potent in vivo eosinophil chemoattractant activity. Preliminary characterization of the cloned C-C chemokine receptors suggests that different receptor subtypes have the capacity to interact with identical ligands. This implies that effector cells will only respond to a given chemokine if a particular receptor is expressed in that cell.
