Effect of the anti-CD66b MoAb 80H3 on the GM-CSF–stimulated neutrophil-mediated Lym-1 antibody-dependent cytolysis. ⁵¹Cr-labeled Raji cells were at 2 × 10⁴. The neutrophil-Raji cell ratio was 20:1. Lym-1 and GM-CSF were at 10 μg/mL and 1 ng/mL, respectively. The incubation time was 14 hours. The lysis was 24.5 ± 12.83 (mean ± 1 SD, n = 6) with a median of 21.45 (confidence interval 95%, 11.04 to 37.86) in the absence of 80H3 and 5.92 ± 8.22 (mean ± 1 SD, n = 6) with a median of 1.30 (confidence interval 95%, −2.71 to 14.55) in the presence of 4 μg/mL 80H3. Cytolysis in the absence versus that in the presence of 4 μg/mL 80H3 was P = .0087.