Cell surface-expressed moesin-like receptor regulates T cell interactions with tissue components and binds an...

Area of Science:

• Immunology
• Cell Biology
• Biochemistry

Background:

• Leukocyte adhesion to the extracellular matrix (ECM) is regulated by chemotactic signals and cell surface receptors.
• Ezrin, radixin, and moesin proteins link the plasma membrane to the actin cytoskeleton, but moesin's role in T cell adhesion is not fully understood.
• Previously, interleukin-2 (IL-2) peptides were found to modify activated T cell adhesion to ECM ligands.

Purpose of the Study:

• To investigate the adhesion-regulatory effects of the IL-2 peptide EFLNRWIT on T cells.
• To identify the receptor responsible for EFLNRWIT-mediated T cell adhesion.

Main Methods:

• T cells were exposed to the EFLNRWIT peptide to assess adhesion to vessel wall and ECM components.
• Radiolabeled peptide binding assays, immunoprecipitation, and amino acid sequencing were used to identify the EFLNRWIT receptor.
• Inhibition assays using anti-moesin monoclonal antibodies (mAbs), recombinant moesin, and soluble moesin were performed.

Main Results:

• The EFLNRWIT peptide induced T cell adhesion to ECM components independently of other activators.
• Peptide binding and sequencing identified a moesin-like moiety on the T cell surface as the receptor for EFLNRWIT.
• Moesin expression increased upon T cell activation, and anti-moesin antibodies/soluble moesin inhibited EFLNRWIT-induced T cell adhesion.

Conclusions:

• The IL-2 peptide EFLNRWIT mediates T cell adhesion through a novel moesin-like receptor expressed on the T cell surface.
• Moesin plays a significant role in T cell responses to adhesion-regulating signals, including IL-2-derived peptides.
• This moesin-like receptor is a key regulator of T cell adhesion to ECM and vessel wall components.