Effects of various concentrations of anti-gp130 MoAbs (○) and TPO-neutralizing Ab (•) on the generation of Mks from CD34⁺ cells stimulated by a complex of IL-6/sIL-6R (A), or TPO (B) in serum-free suspension culture in the presence of SCF. The data from isotype control IgG for anti-TPO Ab (□) and anti-gp130 MoAb (▵) were also presented. 2,000 CD34⁺ cells were cultured in suspension condition and the antibodies were added at the beginning of the culture. Total Mks was calculated based on the proportion of IIbIIIa⁺ cells on the cytospin preparation and total cell number at day 10 of culture. The absolute number of Mks produced in the wells without Abs were presented (*) and estimated as control data. Data indicate the ratio of the total Mks in each well treated with antibodies or control IgG to those from control, and are expressed as percent (%) of the control.