Peptides from the Amino Terminus of Rantes Cause Chemotaxis of Human T-Lymphocytes

Abstract

RANTES is a potent chemotactic and activating agent for a variety of leukocytes including T-lymphocytes. To identify the region of the molecule responsible for this activity, we have made overlapping 10 amino acid peptides scanning the protein. A micro-Boyden chamber chemotaxis assay showed the most efficacious peptides came from at the N-terminus. EC50 values of 8 nM (± 2.2 nM), 3.7 nM (± 2.0 nM) and 3.1 nM (± 2.0 nM) were calculated from dose response curves for the peptides (1-10), (3-12), and (5-14). Control peptides from other regions are not active. In THP-1 cells, none of the peptides give a Ca2+ response. The active peptides are shown to be principally chemotactic rather than chemokinetic by a checker board analysis. The results imply that the principal region of RANTES responsible for chemotaxis is located in the amino terminus.