VASOACTIVE-INTESTINAL-PEPTIDE (VIP) MESSENGER-RNA EXPRESSION IN RAT T-LYMPHOCYTES AND B-LYMPHOCYTES

Different evidence suggests that VIP has immunoregulatory functions an d may be secreted by different cells involved in inflammatory and immu ne responses. In the present study, we demonstrate by reverse transcri ption (RT) and polymerase chain reaction (PCR) VIP gene expression in rat thymocytes and T and B cells derived from spleen and lymph nodes. We have obtained a specific VIP cDNA product of 458 bp identical in si ze to that obtained from cerebral cortex. These results have been conf irmed by Southern blot analysis. VIP message has also been detected in the T-T hybridoma YH-1633 and in a non-immune cell line, the pheochro mocytoma PC 12. VIP gene expression in central and peripheral lymphoid organs suggests that VIP may be a T and B cell-derived cytokine invol ved in T-cell differentiation and in cell immune responses.