the results obtained by [ 35s ] methionine labeling , immunoblotting , immunoprecipitation , fluorescence microscopy , ultracytochemistry , immunogold labeling , and silver enhancement experiments revealed that thrombospondin secreted by endothelial cells is structurally organized together with proteoheparan sulfate in spherical granules at the cell surface .
C0076560
thrombospondin
C0225336
endothelial cells