Production of a monoclonal antibody to an attachment protein derived from human cementum

Abstract

Cementum is the mineralized structure that covers the surface of the roots of teeth; it serves as the attachment site for collagen fibers of adjacent soft connective tissues. Very little is known about how cementum formation is regulated or how it affects other periodontal structures. We have raised a monoclonal antibody that may aid in studies to determine the biology and function of cementum. Mice were immunized with a 55-kDa attachment protein partially purified from human cementum and a monoclonal antibody, H166, was produced. Incubation of tissue sections with this antibody and fluorescein isothiocyanate-conjugated secondary antibody revealed that it immunostains cementum but not dentin, gingiva, or periodontal ligament. Alveolar bone did not bind the antibody, although a few paravascular cells were positive. Long bones, kidney, liver, skin, and several other tissues were negative. Protein fractions separated from cementum extracts by binding to immobilized H166 column contained 55-, 49-, 39-, 29- to 31-, and 23- to 26-kDa components that cross-reacted with the antibody in Western blots; these components were previously shown to be derived from a common precursor. We conclude that the antibody recognizes a group of proteins related to 55-kDa attachment protein in cementum. Our data show that the antibody could serve as a marker for cementum.

Signaling Reactions Induced in Human Fibroblasts During Adhesion to Cementum-Derived Attachment Protein

“…(24,25) The distribution of this protein, cementumderived attachment protein (CAP), appears to be limited to cementum. (26) The CAP promotes cell adhesion at least as well as FN, and among the periodontal cells, alveolar bone cells and fibroblast subpopulations bind and adhere to CAP-coated surfaces with different affinities. (24,27) In contrast, epithelial cells do not adhere to CAP.…”

Localización de las proteínas específicas del cemento radicular CEMP1 y CAP en células neoplásicas

“…Estudios previos han demostrado que CEMP1 contribuye a disminuir la expresión de marcadores relacionados con la mineralización como Runx2 y osteocalcina en células del ligamento periodontal [9][10][11]19 . La contribución de CEMP1 en la formación de tejidos mineralizados a través de la modulación de moléculas en los fibroblastos, debe constituir un proceso importante en el metabolismo óseo, y quizás sea capaz de estimular otras funciones y procesos celulares en células malignas en todos los estadios de la tumorogénesis, particularmente en aquellos tumores que evolucionan a una enfermedad metastásica ósea.…”

“…Por otro lado la Proteína de Adhesión al Cemento (CAP), es considerada como una proteína específica de cemento presente en la matriz madura de cemento radicular en el periodonto adulto y en los cementoblastos, además, las células progenitoras del ligamento periodontal estimuladas con CAP expresan fosfatasa alcalina y forman tejidos mineralizados in vitro 9,10 .…”

“…La formación de tejidos mineralizados estimulada por CEMP1 y CAP se ha atribuido a la modulación de moléculas regulatorias en fibroblastos [9][10][11][12] , dicho proceso puede ser crucial en el metabolismo óseo.…”

Cementum attachment protein/protein-tyrosine phosphotase-like member A is not expressed in teeth

“…When isolated from human or bovine cementum, CAP has a molecular mass of 55-56 kDa. Two monoclonal antibodies were generated against CAP (5,6). Experiments with these antibodies revealed that CAP was restricted to the cementum matrix and to cementoblasts.…”