Differential expression of cytokines in NQ22 and NQ29 lymphoma cells.

Total RNA was extracted from 10⁷ NQ22 and NQ29 cells grown in vitro, from a spleen heavily infiltrated with NQ22 cells, from NQ22 cells cocultured with H-end80 cells, and from NQ29 cells from a subcutaneous tumor mass. RNA was reverse transcribed and amplified with primers specific for IL-1β, IFN-γ, TNF-α, GM-CSF, and HPRT as detailed in “Materials and methods.” Aliquots of the nested PCRs were separated by 2% agarose gel and visualized by ethidium bromide and ultraviolet light. Only the relevant part of the gel is shown.