Elevated expression of the CD4 receptor and cell cycle arrest are induced in Jurkat cells by treatment with the novel cyclic dinucleotide 3',5'-cyclic diguanylic acid.

The effect of the novel, naturally occurring nucleotide cyclic diguanylic acid (c-di-GMP) on the lymphoblastoid CD4+ Jurkat cell line was studied. When exposed to 50 microM c-di-GMP, Jurkat cells exhibited a markedly elevated expression of the CD4 receptor of up to 6.3-fold over controls. C-di-GMP also causes blockage of the cell cycle at the S-phase, characterized by increased cellular thymidine uptake, reduction in G2/M-phase cells, increase in S-phase cells and decreased cell division. Additionally c-di-GMP naturally enters these cells and binds irreversibly to the P21ras protein. The effects described appear to be unique for c-di-GMP.