Chemokine receptor specific for IP10 and mig: structure, function, and expression in activated T-lymphocytes

Area of Science:

• Immunology
• Molecular Biology
• Cell Biology

Background:

• Chemokines are crucial for immune cell trafficking.
• Specific chemokine receptors mediate selective cell migration.
• Understanding T-cell recruitment is vital for immune response modulation.

Purpose of the Study:

• To clone and characterize a novel human receptor selective for CXC chemokines IP10 and Mig.
• To investigate the expression pattern and functional role of this new receptor.

Main Methods:

• cDNA cloning and sequencing of the receptor.
• Analysis of amino acid identity with known chemokine receptors.
• Expression analysis in various immune cell types via quantitative methods.
• Functional assays including calcium (Ca2+) mobilization and chemotaxis.

Main Results:

• A novel G-protein coupled receptor cDNA of 1104 bp was identified, encoding a 368-amino acid protein.
• The receptor shares sequence homology with IL-8 receptors and CC chemokine receptors.
• High expression was observed in IL-2-activated T-lymphocytes, but not in resting T-cells, B-cells, monocytes, or granulocytes.
• The receptor mediates calcium mobilization and chemotaxis specifically in response to IP10 and Mig, with no cross-reactivity to other tested chemokines.

Conclusions:

• A new chemokine receptor, selective for IP10 and Mig, has been discovered.
• Its exclusive expression on activated T-lymphocytes indicates a specific role in effector T-cell recruitment.
• This finding provides insights into the targeted migration of immune cells during inflammatory responses.