Figure 10.

Impact of variation in the anti-CD3:anti-CD28 coating ratio on the efficacy of anti-CD3/CD28 beads in restimulating previously expanded CD4 (upper panel) and CD8 (lower panel) T cells. CD4 cells expanded most extensively in response to soluble anti-CD3 plus irradiated MMCs or beads coated at a very low anti-CD3:anti-CD28 ratio. Expansion was inhibited by higher levels of anti-CD3 coating. CD8 cells also responded better to beads coated at a low anti-CD3:anti-CD28 ratio, but even at the lowest ratio tested, beads were considerably less effective than anti-CD3/MMCs in promoting cell growth.