Effects of goat anti-μ F(ab′)2 on telomerase activity, proliferation, and survival in B-CLL cells. B-CLL cells from 17 cases each of the U-CLL and M-CLL subgroups were cultured alone or with F(ab′)2 fragments of goat anti-μ Ab. (A) Effect of BCR crosslinking on induction of telomerase activity. Four of 17 M-CLL clones (open symbols) show significant induction in telomerase activity. Fold increases in telomerase activity induced in U-CLL and M-CLL subgroups are comparable. (B) Goat anti-μ goat induced proliferative responses in 3 of 17 U-CLL and 5 of 17 M-CLL cases. (C) In a subset of 10 each of the cases studied for panel A, a comparison of the effects of the goat anti-μ F(ab′)2 with HB57-dex was performed. Note that, in 9 of 10 U-CLL cases, stimulation using HB57-dex resulted in rescue from spontaneous apoptosis, whereas 8 of 10 U-CLL cases showed an increase in apoptosis with the goat anti-μ F(ab′)2 Ab. Marginal (< 10%), insignificant rescue from apoptosis using HB57-dex was observed in 4 of 10 M-CLL cases.
