Red blood cell deformability upon continuous or repetitive loadings

This paper focuses on the comparison of red blood cell (RBC) deformability under continuous and repetitive loadings. We utilized a feedback position-control system and a narrow microfluidic channel for applying different deformation patterns on RBCs. According to the analyses of shape recoveries with different patterns, we found, for the first time, that the mechanical responses of RBCs upon continuous and repetitive loadings are almost the same within the error among cellular individualities as long as the total duration of the loading is the same. The result indicates that the internal mechanical stress on RBCs accumulates even if the apparent cell shape recovers. The finding provides quantitative insights for the systematic comparison among various existing measurement methods of mechanical responses of cells.