CNRS, Institut de Physique de Rennes, Département Matière molle, UMR UR1-CNRS 6251, Université de Rennes1, F-35042, Rennes, France.
INSERM, Laboratoire Traitement du Signal et de l'Image, UMR UR1-INSERM U642, Université de Rennes1, F-35042, Rennes, France.
Sci Rep. 2017 Sep 22;7(1):12197. doi: 10.1038/s41598-017-12398-0.
Polarization dependence second harmonic generation (P-SHG) microscopy is gaining increase popularity for in situ quantification of fibrillar protein architectures. In this report, we combine P-SHG microscopy, new linear least square (LLS) fitting and modeling to determine and convert the complex second-order non-linear optical anisotropy parameter ρ of several collagen rich tissues into a simple geometric organization of collagen fibrils. Modeling integrates a priori knowledge of polyhelical organization of collagen molecule polymers forming fibrils and bundles of fibrils as well as Poisson photonic shot noise of the detection system. The results, which accurately predict the known sub-microscopic hierarchical organization of collagen fibrils in several tissues, suggest that they can be subdivided into three classes according to their microscopic and macroscopic hierarchical organization of collagen fibrils. They also show, for the first time to our knowledge, intrahepatic spatial discrimination between genuine fibrotic and non-fibrotic vessels. CCl-treated livers are characterized by an increase in the percentage of fibrotic vessels and their remodeling involves peri-portal compaction and alignment of collagen fibrils that should contribute to portal hypertension. This integrated P-SHG image analysis method is a powerful tool that should open new avenue for the determination of pathophysiological and chemo-mechanical cues impacting collagen fibrils organization.
偏振依赖二次谐波产生（P-SHG）显微镜在原位定量纤维蛋白结构方面的应用越来越受到关注。在本报告中，我们结合 P-SHG 显微镜、新的线性最小二乘法（LLS）拟合和建模，确定并将几种富含胶原蛋白的组织的复杂二阶非线性光学各向异性参数 ρ 转换为胶原蛋白纤维的简单几何组织。该模型整合了胶原蛋白分子聚合物的多螺旋组织以及纤维和纤维束的先验知识，以及检测系统的泊松光子噪声。结果准确预测了几种组织中已知的亚微观胶原纤维的分层组织，表明它们可以根据胶原纤维的微观和宏观分层组织分为三类。此外，它们还首次展示了我们所知的肝内真正纤维化和非纤维化血管之间的空间分辨。CCl 处理的肝脏的特征是纤维化血管的百分比增加，其重塑涉及门脉周围的压缩和胶原蛋白纤维的排列，这应该有助于门脉高压。这种集成的 P-SHG 图像分析方法是一种强大的工具，应该为确定影响胶原蛋白纤维组织的病理生理和化学机械线索开辟新的途径。
