COMPARISON OF EFFICACY OF ANTISENSE OLIGOMERS DIRECTED TOWARD TNF-ALPHA IN HELPER-T AND MACROPHAGE CELL-LINES

The authors investigated the use of antisense oligomers specific for T NF-alpha (AS-2) and nonsense control oligomers (NS) in T cells (HT2) a nd macrophages (RAW264.7), comparing three distinct chemical formulati ons, Phosphorothioate antisense (S-AS) caused sequence-specific inhibi tion of TNF-alpha, production by activated HT2s (0.5 mu M S-AS 2 vs S- NS: 31.4 +/- 1.2%, 4.2 +/- 3.2% inhibition, respectively), In contrast , S-AS were ineffective in RAW264.7, despite greater uptake as measure d with fluorescent S-oligonucleotides. Furthermore, differences in eff icacy of S-AS (HT2 > RAW) were not attributable to differences in the pinocytic (HT2 = RAW) or adsorptive endocytic (RAW > HT2) pathways imp licated in oligonucleotide uptake, suggesting an important role for in tracellular events after antisense uptake, Morpholino oligomers (M-AS) , in contrast, were more effective in RAW264.7 than in HT2 (32.6 +/- 2 .6% vs 12.3 +/- 0.5% inhibition), consistent with uptake experiments u sing fluorescent M-oligomers. Phosphodiester oligonucleotides were ine ffective in both cell types, It was concluded that antisense efficacy in leukocytes varies according to type of oligomer, cell target and in tracellular processing event(s). (C) 1997 Academic Press Limited.