Bovine Reissner's fiber (RF) and the central canal of the spinal cord: an immunocytochemical study using a set of monoclonal antibodies against the RF-glycoproteins

Abstract

The subcommissural organ secretes N-linked complex-type glycoproteins into the cerebrospinal fluid. These glycoproteins condense to form Reissner's fiber (RF), which extends along the fourth ventricle and central canal of the spinal cord. A set of three monoclonal antibodies (Mabs 3E6, 3B1, and 2A5) has been obtained using these glycoproteins as immunogens. Competitive and sandwich enzyme-linked immunoassay methods have demonstrated that the three monoclonal antibodies are directed against different epitopes, and that there is no competition among them for their binding to glycoproteins of RF. Mab 3E6 displays immunoblotting properties that are similar to those of a polyclonal antibody against the pool of glycoproteins from RF, but that are different from those of Mabs 3B1 and 2A5. All three antibodies immunostain the bovine subcommissural organ and RF. A population of ependymal cells is stained by the polyclonal antibody, and Mabs 2A5 and 3E6, but not by Mab 3B1. The material present in a population of ependymal cells of the central canal, and the glycoproteins secreted by the subcommissural organ thus probably have partial chemical identity. Some evidence suggests that the immunoreactive ependymal cells are secretory cells. The luminal surface of the central canal is coated by a thin layer of material with immunocytochemical characteristics different from those of the ependymal cells; such a coat may correspond to material released from RF.

Tenascin-Y in the Developing and Adult Avian Nervous System

“…Remarkably similar staining of long, beaded processes has been observed by others using antibodies raised against the glycoproteins of Reissner's fiber, a thread-like strand of extracellular matrix that extends the length of brain ventricles and into the spinal cord's central canal [Karoumi et al, 1990;Rodriguez et al, 1996;Perez et al, 1996;Yulis et al, 1998]. Our staining pattern indicates that tenascin-Y in the chicken, and probably tenascin-X in mammals, is in either Reissner's fiber or more nebulous parts of the ventricular matrix.…”

Biosynthesis and molecular biology of the secretory proteins of the subcommissural organ

“…After Sterba's early reports, only a few studies have been performed to analyze the biochemical properties of RF. In the last decade, several biochemical studies have been performed using native and denaturing extracts of RF Meiniel et al, 1993;Nualart, 1995;Nualart and Rodríguez, 1996;Nualart et al, 1991;Pérez et al, 1996;Rodríguez et al, 1987). When RF was extracted in ammonium bicarbonate and processed for electrophoretic analysis under non-denaturing conditions, only two bands were detected.…”

“…Pérez et al (1996) Molecular cloning of bovine SCO specific cDNA. Isolation of a SCO cDNA of 2.5 kb.…”

“…1). RF grows caudally and extends along the brain aqueduct, the fourth ventricle, and the whole length of the central canal of the spinal cord Oksche, 1969;Olsson, 1993;Pérez et al, 1996;Rodríguez et al, 1985Rodríguez et al, , 1998Sterba et al, 1967;Wolf and Sterba, 1972).…”

Analysis and quantification of the secretory products of the subcommissural organ by use of monoclonal antibodies

“…At variance, a mono-clonal antibody (Mab) recognize a single epitope of the antigen and this makes them valuable, precise tools for morphological, analytical, and functional studies of the SCO-RF system (Meiniel et al, 1988;Pérez et al, 1995Pérez et al, , 1996. In this work, we describe the production and use of a series of Mabs against both the bovine RF and the secretory glycoproteins extracted from the bovine SCO.…”