Effect of HDAC1, -2, -3, and -8 siRNA transfection on OX40L expression. HL cell lines were transfected with HDAC1, -2, -3, and -8 siRNA and cells were analyzed for OX40L expression after 48 hours of incubation. Inhibition of expression of HDAC1, -2, -3, or -8 had little or no effect on OX40L expression in HL cells.