Figure 5

Adhesive force of immature and mature BMDCs. (A) As shown in Figure 5A (slightly modified from Shahin et al.[29, 30]), the AFM tip is moved toward the cell surface (1) and then retracted at a constant lateral position (2) and (3). During the AFM tip retraction, the AFM tip with the sample leads to a force signal with a distinct shape (4). The force increases until bond rupture occurs (5) at an unbinding force; (B a and b) The typical force-distance curves were recorded with using an non-functionalized AFM tip to measure the adhesive force of the immature BMDCs treated with 10.0 μg/L of GM-CSF plus 10.0 μg/L of IL-4 (B a) or the mature BMDCs stimulated with 1.0 mg/L of LPS (B b). The measured adhesion force (352.37 ± 11.71 pN) on the membrane surface of the mature BMDCs was much bigger than that (70.37 ± 4.55 pN) of the immature BMDCs (n = 10; P < 0.01).