title: The adult macaque spinal cord central canal zone contains proliferative cells and closely resembles the human.
abstract: The persistence of proliferative cells, which could correspond to progenitor populations or potential cells of origin for tumors, has been extensively studied in the adult mammalian forebrain, including human and nonhuman primates. Proliferating cells have been found along the entire ventricular system, including around the central canal, of rodents, but little is known about the primate spinal cord. Here we describe the central canal cellular composition of the Old World primate Macaca fascicularis via scanning and transmission electron microscopy and immunohistochemistry and identify central canal proliferating cells with Ki67 and newly generated cells with bromodeoxyuridine incorporation 3 months after the injection. The central canal is composed of uniciliated, biciliated, and multiciliated ependymal cells, astrocytes, and neurons. Multiciliated ependymal cells show morphological characteristics similar to multiciliated ependymal cells from the lateral ventricles, and uniciliated and biciliated ependymal cells display cilia with large, star-shaped basal bodies, similar to the Ecc cells described for the rodent central canal. Here we show that ependymal cells with one or two cilia, but not multiciliated ependymal cells, proliferate and give rise to new ependymal cells that presumably remain in the macaque central canal. We found that the infant and adult human spinal cord contains ependymal cell types that resemble those present in the macaque. Interestingly, a wide hypocellular layer formed by bundles of intermediate filaments surrounded the central canal both in the monkey and in the human, being more prominent in the stenosed adult human central canal.
authors.affiliation: Laboratorio de Neurobiología Comparada, Instituto Cavanilles, Universidad de Valencia, CIBERNED, Valencia, 46980, Spain.
authors.forename: Clara
authors.initials: C
authors.lastname: Alfaro-Cervello
authors.forename: Arantxa
authors.initials: A
authors.lastname: Cebrian-Silla
authors.forename: Mario
authors.initials: M
authors.lastname: Soriano-Navarro
authors.forename: Patricia
authors.initials: P
authors.lastname: Garcia-Tarraga
authors.forename: Jorge
authors.initials: J
authors.lastname: Matías-Guiu
authors.forename: Ulises
authors.initials: U
authors.lastname: Gomez-Pinedo
authors.forename: Pilar
authors.initials: P
authors.lastname: Molina Aguilar
authors.forename: Arturo
authors.initials: A
authors.lastname: Alvarez-Buylla
authors.forename: Maria-Rosario
authors.initials: MR
authors.lastname: Luquin
authors.forename: Jose Manuel
authors.initials: JM
authors.lastname: Garcia-Verdugo
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D000818:Animals; D049109:Cell Proliferation / Q000502:physiology*; D004847:Epithelial Cells / Q000502:physiology; D005260:Female; D006801:Humans; D008251:Macaca; D008252:Macaca fascicularis; D008297:Male; D013045:Species Specificity; D013115:Spinal Canal / Q000166:cytology* / Q000502:physiology* / Q000648:ultrastructure; D013116:Spinal Cord / Q000166:cytology* / Q000502:physiology* / Q000648:ultrastructure
keywords: central canal; cilia; ependyma; neural stem cells; primate; spinal cord