EXPRESSION OF CYTOKINE MESSENGER-RNA UNDE R PHYSIOLOGICAL CONDITIONS IN NORMAL MICE

The expression of the cytokine genes was studied under physiological c onditions in normal adult mice using RT-PCR method capable of detectin g low levels of mRNA. Total RNA was prepared from brain, spinal cord, lung, spleen, liver and kidney of 6 to 8 week-old specific pathogen-fr ee BALB/c mice by acid guanidinium thiocyanate-phenolchloroform (AGPC) method. cDNA was synthesized by M-MLV reverse transcriptase, and ampl ified using the specific oligonucleotide primers for IL-1, IL-2, IL-3, IL-4, IL-5, IL-6, TNF-alpha, IFN-alpha, IFN-beta and IFN-gamma by PCR method. Although IL-1 mRNA was detected in all the organs, IL-3 mRNA was not detected in any organs tested. IL-2 or IL-4 mRNA and IL-5 mRNA were produced only in spleen and lung, respectively. However, IL-6, T NF-alpha and IFN mRNA were detected in some different organs. These re sults suggest that many kinds of cytokine mRNA were produced in vivo u nder physiological conditions in normal mice.