IL-3 and TNF-α enhance DC precursor proliferation and growth without altering their phenotype or their functionality. (A) Adherent ACs were cultured for 4 days in the presence of different cytokine combinations as described in Materials and Methods. Cell proliferation was evaluated by a 12-hour pulse with 3H-TdR and results are expressed as mean ± SD of sextuplet cultures. One representative experiment out of four performed with ACs from four MM patients is shown. The number of DCs generated in the different culture groups was counted and expressed as the percentage of the initial cell number put into culture. Results are the mean ± SD of the DC yields obtained in the four experiments using ACs from the four patients. (B) Graded numbers of DCs were used as stimulator cells for 1.5 × 105 thawed allogenic T cells. 3H-TdR incorporation of irradiated (30 Gy) DCs or purified T cells were less than 800 cpm.
