Tenascin during gut development: appearance in the mesenchyme, shift in molecular forms, and dependence on epithelial-mesenchymal interactions [published erratum appears in J Cell Biol 1989 Mar;108(3):following 1175]

Abstract

Abstract. Tenascin, an extracellular matrix protein, is expressed in the mesenchyme around growing epithelia in the embryo. We therefore investigated whether epithelial cells can stimulate expression of tenascin in embryonic mesenchyme. Mesenchyme from the presumptive small intestine was used because it is known that reciprocal epithelial-mesenchymal interactions are important for gut morphogenesis. Rat monoclonal antibodies against mouse tenascin were raised and were found to react specifically with mouse tenascin in ELISA. In supernatants of cultured fibroblasts, the antibodies precipitated two peptides of Mr 260 and 210 kD. One of the antibodies also reacted with these tenascin chains in immunoblots of tissue extracts. We found that tenascin was absent during early stages of gut development, at stages when the mesenchyme is already in contact with the stratified epithelium of the endoderm. Rather, it appeared in the mesenchyme when the homogenous endodermal epithelium differentiated into the heterogenous absorptive epithelium.Tenascin remained present in the stroma of the adult gut, close to the migration pathways of the continuously renewing epithelium. When first detected during intestinal differentiation, the 210-kD component was predominant but at birth the relative amount of the 260-kD component had increased. The expression data suggested that the appearance of tenascin in the mesenchyme was dependent on the presence of epithelium. To test this, isolated gut mesenchymes from 13-d-old mouse embryos were cultured for 24 h either alone or together with epithelial and nonepithelial cells. Whereas mesenchyme cultured alone or in the presence of nonepithelial B16-F1 melanoma cells produced only trace amounts of tenascin, expression was strongly stimulated by the epithelial cell line, Madin-Darby canine kidney (MDCK). We propose that growing and differentiating epithelia produce locally active factors which stimulate synthesis of tenascin in the surrounding mesenchyme.

Tenascin variants: differential binding to fibronectin and distinct distribution in cell cultures and tissues.

“…This variant is not detectable anymore in adult gizzard smooth muscle but is instead expressed underneath the differentiating epithelium. These shifts in molecular forms of tenascin variants during gizzard development are reminiscent of the situation reported for gut development in the mouse (Aufderheide and Ekblom, 1988). It is possible that the late appearance of the largest form of tenascin in the gut of newborn mice could correlate with the final differentiation of the epithelial cells of the crypts where tenascin has been postulated to promote cell shedding (Probstmeier et al, 1990).…”

Epithelial synthesis of tenascin at tips of growing bronchi and graded accumulation in basement membrane and mesenchyme

“…It has therefore been postulated that the protein is required for mesenchymalepithelial interactions during morphogenesis. Corresponding data were provided by studies on developing vibrissae, mammary gland, tooth [5], feathers [6], kidney [7], gut [8], and neural tube 191. These studies showed that tenascin is predominantly accumulated around actively growing epithelia in basement membrane and mesenchyme.…”

Tenascin-C: Exploitation and collateral damage in cancer management

“…53 The BFC was designed to give a better thermodynamic stability and to prevent hydrolysis in vivo. The synthesized L* was tested for its ability to be coupled to the monoclonal antibodies B28-13, an antibody recognizing human tenascin-C 8 or to MTn12, an antibody recognizing murine tenascin-C. 56 This work has shown that the ligand L* can be coupled to primary amines but also to large biomolecules, the antibodies B28-13 53 and MTn12. 54 Immunostaining on respective human or murine cancer tissue further confirmed the ability of coupled B28-13 or MTn12 to retain its affinity toward tenascin-C. 53,54 Although a careful evaluation in vivo is still lacking, the developed activated phosphonated BFC, especially when coupled to antibodies targeting tenascin-C may provide a new powerful tool to improve metal based imaging diagnostics and radiotherapeutic applications.…”