Figure 4. CCI of sialic acids and AsGM1 in C4-2B cells.

(A) Interaction and binding of C4-2B cells to AsGM1 (solid line, closed squares) and GM1-coatings (solid line, open squares) in comparison with interaction of LNCaP cells to AsGM1 (dashed line, closed circles) and GM1 (dashed line, open circles) (B) the role of sialic acids in the interaction and binding of C4-2B (solid line, closed squares) and sialidase-treated C4-2B cells (solid line, open squares) and LNCaP (dashed line, closed circles) and sialidase-treated LNCaP cells (dashed line, open circles) to AsGM1-coated layers. (C) The effect of removal of sialic acids (open squares and circles) or/and blocking of the α2β1 integrin receptors (dashed lines) on the interaction of C4-2B cells to AsGM1-coated layers (solid line, closed squares) and (D) the effect of removal of sialic acids (open squares and circles) or/and blocking of AsGM1 (dashed lines) on the interaction of C4-2B cells to AsGM1-coatings (solid line, closed squares). For all experiments, 5×10⁴ sialidase-treated (0.5 U/ml sodium citrate buffer pH 6 for 1 h at 37°C) or untreated LNCaP and C4-2B cells/100 μl, were incubated on AsGM1- or in respective experiment on GM1-coated layers for indicated times, in the presence or absence of function blocking integrin α2β1 (5 μg/ml) or AsGM1 (1:500) antibodies. Adherent cells were determined at each time point, by measuring acid phosphatase activities and results are expressed as relative absorbance, taking in account non-specific binding using IgG isotype control antibodies. Six to eight wells were analysed in each experiment. All data are means±S.D. from three independent experiments (P<0.05).