**5. Conclusions**

In this study, we used rheometer and bionic microfluidic devices to investigate and evaluate the effect of injury erythrocytes on flow patterns in bionic arterioles with stenosis segment. The variation of PFH concentration under different shear stress and exposure time in rheometers showed that the long exposure time in high shear stress environments would induce more damage of erythrocytes. Meanwhile, LDH release with gradient changes under different shear stress and exposure times revealed that high shear stress was the main factor causing erythrocyte membrane injury, and a long exposure time could aggravate this trauma. Following this rheometer test, the damaged erythrocytes were collected and injected into a bionic microfluidic device which was designed to mimic arterioles with several continuous stenosis segments, to investigate and evaluate the flow pattern modification by red cell damage at different degrees. The results show that with the increase of shear stress, the migration rate of damaged erythrocyte declined and the aggregation of erythrocyte was clearly observed in bionic microchannels, which was consistent with the degree of erythrocyte damage assessed through the rheometer test. Our results indicate that mechanical shear stress was caused by erythrocyte injury, which enhanced aggregation ability of erythrocytes and increased blood viscosity and resulted in decreased blood rheological performance, eventually leading to thrombus formulation and adhesion in arterioles.

**Author Contributions:** D.L. and G.L. developed the concept of the article and wrote the outline of the paper draft; Y.Z. supported work in funding and reviewed the paper; H.C. reviewed the paper; Y.C. and J.M. analyzed the data; Q.W. and M.Z. redacted the paper. All authors of this article provided substantive comments.

**Funding:** This research was funded by Tsinghua University Initiative Scientific Research Program, grant number 20141081265.

**Acknowledgments:** Guiling Li acknowledges the support from Center for Life Sciences at Tsinghua and Peking Universities. Jia Man acknowledges the support from Key Laboratory of High-efficiency and Clean Mechanical Manufacture at Shandong University, Ministry of Education.

**Conflicts of Interest:** The authors declare no conflict of interest.
