Abstract
PURPOSE: To study the platelet adhesion and aggregation behaviour of late pregnancy women under arterial shear rate using microfluidic chip technology and evaluate the risk of thrombosis in late pregnancy. METHODS: We included pregnant women who were registered in the obstetrics department of our hospital between January 2021 and October 2022 and underwent regular prenatal examinations. Blood samples were collected at 32-35 weeks of gestation for routine blood tests and progesterone, oestradiol, and platelet aggregation function. A microfluidic chip was used to construct an in vitro stenosis vascular model to explore the platelet reactivity at shear rates of 1000s-1, 1500s-1 and 4000s-1. Flow cytometry was used to analyse the effect of shear rate induction on the expression of platelet membrane surface fibrin receptor (PAC-1) and P-selectin (CD62P) in pregnant women. RESULTS: Compared to the non-pregnant healthy control group, the white blood cell count increased and platelet count decreased significantly in late pregnant women (P < 0.05), and platelet reactivity to agonists increased under non-flow conditions (adhesion and aggregation rates, P < 0.05). Microfluidic chip technology showed that platelet aggregation in late pregnant women increased significantly (P < 0.05) in the shear-rate environment and was positively correlated with the shear rate. The degree of aggregation at 4000s(-1) was more evident, but the stability of platelet aggregates was low. Shear rate increased PAC-1 and CD62P expression. CONCLUSION: Microfluidic chip technology was used to analyse the platelet aggregation function under arterial shear rate combined with flow cytometry to detect platelet activation, which was consistent with the traditional non-flow conditions used to evaluate platelet function. However, microfluidic technology can simulate a more realistic in vivo shear rate environment, providing more effective clinical application data and a theoretical basis for the diagnosis and prevention of platelet dysfunction and thrombotic diseases during pregnancy.