Effects of flowing red blood cells on the motion of a circulating tumour cell in the asymmetric bifurcated microvessel

Asymmetric bifurcate are common in the vascular system, and circulating tumour cells (CTCs) tend to metastasize at these locations. In this study, the dissipative particle dynamics method is used to simulate the motion of a CTC in an asymmetric microvessel combined with a spring-based network model. Effects of flow rate, the presence of RBCs and haematocrit on the motion of the CTC are investigated. The results indicate that under higher flow rate, the CTC could not adhere to the microvessel and invariably migrated towards the branch exhibiting a higher flow rate. In the presence of RBCs, the initially attached CTC would disassociate from the parent vessel wall under the collisions with them, and it finally enters into the large branch. While at lower flow rates, the RBCs pass over the CTC that is rolling along the top wall of the parent vessel and overtake it, facilitating the CTC adhesion, it ultimately moves into the small branch. At a mediate flow rate, though the attached CTC detaches and enters into the large branch, it would touch the inner wall of the branch. With the haematocrit increasing up to 5.1%, the CTC retains rolling along the vessel wall and is ultimately captured in the small branch.