Figure 8. Aggregation assay using ACAM stably transfected CHO-K1 cells.

(A) pcDNA3.1 transfected CHO-K1 cells, as control, show scattered single cell suspension. (B) In low expression cell line, small cell aggregates consisting of 10-15 cells are observed. (C) Larger aggregates are found in high expression cell line after 90 min of incubation. (D) The initial particle number (N₀), identical to the total number of the cells added to the medium, and the particle number at 90 min of incubation (N₉₀) was measured with Coulter counter. The aggregation index, (N₀−N₉₀)/N₀, is significantly higher in the high expression cell line (33.8±7.4%) than pcDNA3.1-transfected CHO-K1 cells (9.8±6.4%).The results are expressed as the means±S.D; *P<0.001. Scale bars, 200 μm.