IL-10 secretion by the UV-induced B cell lymphomas. The cells were grown in vitro without any further stimulation. Supernatants from duplicates of three Petri dishes were collected at 24, 48 and 72 hours and were analyzed individually. Each column represents the average in IL-10 concentration of 6 samples. The only cytokine detected in the supernatant fluid was IL-10. The bar indicates the standard error of the mean (SEM).