Retinoic acid regulated insulin-like growth factor gene expression in cordblood lymphocytes

Objective To explore the immune promotion mechanism of retinoic acid (RA). Methods Reverse Transcription-Polymerase chain reaction (RT-PCR) was used t o detect the gene expression of insulin like growth factor I (IGF I) and IG F receptors (IGF-IR and IGF-IIR) in vitro, and their regulation by RA in hu man cord blood lymphocyte (CBL). Results Significant upregulation of IGF-I, IGF-IR and IGF-IIR mRNA was foun d at 6 - 24 hours in CBL incubated with physiologic concentrations of RA as compared to those without RA. Conclusion The enhancement of IGF expression may be an important pathway fo r vitamin A to promote immune cellular functions.