结合AFM探测副伤寒沙门氏茵B感染红细胞膜的生物力学特性

采用原子力显微镜和衍射显微术，在纳米精确尺度探测副伤寒沙门氏菌B（Sp B）感染宿主红细胞（RBC）膜微观结构和力学特性，涉及细胞的形变、膜面内剪切模量和弯曲模量。结合这两种单分子测量技术，利用相关的数学模型表述RBC膜对菌体印B的入侵非常敏感。实验结果显示，不同感染期间的SpB寄生菌体，能够引起宿主RBC膜结构改变，形变能力降低，膜剪切模量和弯曲模量显著增加。这些力学特性的变化影响RBC的输氧和循环功能。实验结果表明，印B具有独特的鞭毛调控系统，入侵的毒性菌体寄生蛋白与血影蛋白网络中的运输蛋白有特异结合位点，导致RBC膜骨架网络、波动力学和细胞内、外基质都产生应激反应，这有可能为理解勋曰感染RBC的发病机理和寄生途径提供一些新的实验思路和分析依据。

Probing Membrane Biomechanics of Erythrocytes Parasitized by Salmonella paratyphiB Using Atomic Force Microscopy

Parasitization by Salmonella paratyphi B （Sp B） leads to morphological, structural, biochemical component, and mechanical deformation alterations to the host erythrocytes. To probe these modifications at the nanoscale, we apply atomic force microscopy and diffraction phase microscopy to measure the mechanical properties of red blood cell （RBC） membrane infected by Sp B, including deformability, shear modulus and bending modulus. Combining the two techniques with a new mathematical model describing RBC membrane is very sensitive to the invader of parasitic Sp B. The results demonstrated that the growing parasite in their host RBCs caused structure changes and decreased deformation. Coincident with this morphological transition, there is a significant increase in the membrane＇s shear and bending moduli. This mechanical transition can alter cell circulation and impede oxygen delivery. The results indicated that proteins transported from invading organisms, such as the Ivirulent parasitic Sp B, to specific binding sites in the spectrin network are considered to introduce significant alterations to RBC membrane skeleton network, dynamics and mechanical response. These changes could provide insights into possible mechanistic pathways in the pathogenesis of parasitic Sp B, which may provide new ideas on further experiments and analyses.