Immunomodulatory properties of a new hypoxantine derivative, PCF-39: I. Activation of mature phagocytes and modulation of NK cells

The synthesis of the hypoxanthine derivative Nα-5 (1.6-dihidro-6-oxo-9-purinyl)pentyloxy/carbonyl-L-Arginine, PCF-39 is briefly described. In vitro, results herein presented indicate that PCF-39 modulates the phagocytic cells while being unable to induce terminal differentiation of human leukemic cells, U-937 and HL-60. The NK-activity is also down modulated in mice depending upon age and doses, while NK precursors growth appears to be faster and higher in BM transplanted animals. Data herein presented would confirm what has been previously postulated in immunosuppressed mice treated with PCF-39 before challenging it in several microbial and tumor graft models. Results would indicate that PCF-39 is an interesting synthetic immunomodifier in the family on the hypoxanthine derivatives endowed with immunomodulatory properties.