Human CCL1 antisense oligodeoxynucleotide (ODN) screened as a potent inhibitor of M2b monocytes (INC6P.322)

Abstract

Abstract In a murine model of γ-irradiation, bacterial translocation and subsequent sepsis have been effectively controlled by CCL1 antisense ODN, a M2b macrophage reverter. In the present study, we tried to obtain human CCL1 antisense ODN which is inhibitory on human M2b macrophages. Twenty human CCL1 antisense ODNs were synthesized based on the prediction of CCL1 mRNA secondary structure, calculation of GC content, and binding energy of ODNs. To evaluate the activity of these ODNs, an amount of CCL1 in culture fluids of M2b monocytes cultured with the ODNs was determined by ELISA. M2b monocytes were generated in vitro from healthy donor peripheral blood monocytes after stimulation with IL-1β and IgG in combination. In the results, 2 ODNs (HCA-15 ; CAACATCTGGAGAAGGGT : HCA-17 ; GGGCTGTGGTGATGATC), at doses of 20 and 100 µg/ml, suppressed 70-80% or more of CCL1 production by M2b monocytes. Also, decreased expression of IL-10 and CD163 was shown in M2b monocytes cultured with HCA-15 and HCA-17. The other 18 ODNs were not significantly active on the M2b macrophage reversion. These results suggest that HCA-15 and HCA-17 may be beneficial in controlling bacterial translocation and subsequent sepsis in patients with γ-irradiation.