Antisense oligonucleotides against CD9 reduce or abrogate the enhanced susceptibility to lysis induced by PWM.

Myeloma cell lines COL, MER, ARK, and RLO were used as targets in 4-hour ⁵¹Cr release assays. These myeloma cells were first cultured in the presence of 150 μmol/L CD9 antisense or sense oligonucleotides for 2 hours followed by an additional 2 hours in the presence of 1% PWM prior to labeling with ⁵¹Cr. E:T ratios were 30:1. The data represents the mean values ± SEM of 3 similar experiments. P ≤ .01.