Effect of viral IL-6 antisense oligonucleotides on clonal growth of KSHV-infected lymphoma cell lines. The PEL cell lines (A) KS-1 and (B) BC-1 were cultured in soft agar with either IL-6 sense (□) or antisense (◊) phosphorotioated oligonucleotides at 1, 5, and 10 μmol/L. Results were expressed as a percentage of control cells not exposed to oligonucleotides; results represent the mean ± standard deviation (SD) of three experiments done in triplicate.