It has been shown, that the 2'-5'-oligonucleotide of adenylic acid (de
phosphorylated trinucleotide) possessed the interferon-like growth-mod
ifying activity towards lymphocytes and tumor cells. The orientation a
nd expression of such activity depends on both the nature and dose of
the substance and functional state of the cells tested. This activity
may have alternative directions such as stimulation and inhibition of
the function tested.