Premium
Vasoactive Intestinal Peptide (VIP) Receptor Type 2 (VPAC 2 ) is the Predominant Receptor Expressed in Human Thymocytes
Author(s) -
LARAMARQUEZ MARIA L.,
O'DORISIO M. SUE,
KARACAY BAHRI
Publication year - 2000
Publication title -
annals of the new york academy of sciences
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.712
H-Index - 248
eISSN - 1749-6632
pISSN - 0077-8923
DOI - 10.1111/j.1749-6632.2000.tb06950.x
Subject(s) - vasoactive intestinal peptide , thymocyte , cd8 , receptor , cd3 , cd28 , t cell receptor , biology , microbiology and biotechnology , t cell , immune system , neuropeptide , immunology , biochemistry
A bstract : Vasoactive intestinal peptide (VIP) binding sites have been identified in the human thymus, but the receptor subtype and how these receptors are distributed in the human thymus subsets is unknown. To assess gene expression, distribution, and receptor regulation of the two G‐protein‐associated VIP receptors, VPAC 1 and VPAC 2 mRNAs were quantified using a novel fluorometric‐based kinetic (real‐time) RT‐PCR. Bulk and fractionated thymocytes were stimulated via the TCR/CD3 receptor complex and anti‐CD28. Our results demonstrate that thymocytes express higher levels of VPAC 2 compared to VPAC 1 expression in bulk thymocytes, CD4 + CD8 + selected double positives (DP), and CD8 depleted thymocytes. Double negative cells express low levels of VPAC 2 mRNA. We demonstrate T‐cell activation‐dependent downregulation of VPAC 1 , but not VPAC 2 , in human thymocytes. This study reports the first direct evidence of a differential distribution and selective regulation of VPAC 1 and VPAC 2 gene expression in normal human thymocyte subsets.