Expression pattern of β-catenin during the development of human fetal spinal cord.

Development of the human fetal spinal cord is a very complicated process involving numerous signaling pathways including Wnt signaling pathways. These pathways are critical for the development and function of the mammalian nervous system. β-Catenin is a key molecule in the canonical Wnt signaling pathway. However, the distributions of β-catenin during development of the human fetal spinal cord have not been well characterized. Therefore, in this study, we performed immunohistochemical analysis of the β-catenin distribution in the developing human spinal cord from 35 fetuses at three weeks to eight months of gestation. As early as E3W and E4W, β-catenin was mainly expressed in the internal limiting membrane of the neural tube and neuroepithelium (E: Embryos; W: Weeks). During developmental stages, β-catenin was widely expressed in various structures and cells including the neuroepithelium, internal limiting membrane, mantle layer, marginal layer, basal plate, alar plate, ependyma, gray matter, white matter, neurons with multiple processes, glial cells, and nerve fibers. This study clarifies the morphological developmental characteristics of the human fetal spinal cord as well as the distribution and expression pattern of β-catenin in chronological and spatial aspects. Our results suggest that the Wnt÷β-catenin signaling pathway might play a crucial role in various stages of the formation and differentiation of the human fetal spinal cord.