COLOCALIZATION OF TENASCIN WITH VERSICAN, A HYALURONATE-BINDING CHONDROITIN SULFATE PROTEOGLYCAN

Rabbit antisera against tenascin, a large extracellular matrix protein , in conjunction with monoclonal antibodies of mouse origin against ve rsican, a large hyaluronate-binding proteoglycan, were used to make a comparative study of the distribution of the two antigens in the same cryostat sections by double immunofluorescence. In the central nervous system, tenascin was invariably associated with versican, but the rev erse was not true, in that versican was also found where tenascin was not detectable, particularly in gray matter. There were major species differences in the distribution of tenascin in the central nervous sys tem. In the cow, tenascin was found in cerebral and spinal cord white matter and in the granule cell layer of the cerebellum. In the human b rain, tenascin was found in cerebral white matter but not in the cereb ellum. In the rat, tenascin was mainly confined to brain periventricul ar layer and spinal cord white matter. During the development of the c erebellum of the rat, the tenascin immunoreactivity decreased, and a l ower molecular weight band appeared (J1-160/180/restrictin?) and persi sted throughout adulthood. Tenascin expression was a relatively late e vent in the development of the rat central nervous system, immunoreact ivity being first observed after birth. In the rat embryo, tenascin wa s found to co-localize with versican in precartilaginous mesenchyme an d in connective tissue underlying epithelia. The colocalization of ver sican with tenascin suggests that versican may be the tenascin (cytota ctin)-associated proteoglycan reported in the literature.