Autocrine BAFF or APRIL are involved in the growth of autonomously growing HMCLs. L363 and RPMI8226 cells were starved for 3 hours and cultured without cytokine, or in the presence of TACI-Fc (10 μg/mL) or TACI-Fc (10 μg/mL) and BAFF/APRIL (200 ng/mL BAFF and 200 ng/mL APRIL). Results are the mean values plus or minus SD of the tritiated thymidine incorporation determined on sextuplet culture wells and are expressed as the percentage of the proliferation obtained without cytokine. ^* Mean value is statistically significantly different from that obtained without adding TACI-Fc using a Student t test (P ≤ .05).