Lectin-binding sites in quick-frozen, freeze-substituted extracellular matrix of rabbit corneal stroma: a comparative electron microscopic study with different embedding procedures.
The efficiency of Epon, Lowicryl K4M and LR White resins for electron microscopy was tested on the reactivity of carbohydrate residues to lectins in quick-frozen, freeze-substituted extracellular matrix of rabbit corneal stroma, without the use of any chemical fixation. Three lectins conjugated to gold particles were used in a post-embedding method: Wheat germ agglutinin, Concanavalin A and Ricinus communis agglutinin 1. Best gold-labelling was obtained with Lowicryl K4M for Wheat germ agglutinin, and with both Lowicryl K4M and Epon for Concanavalin A and Ricinus communis agglutinin 1. Tissues embedded in LR White gave less intense labelling for the three lectins used in comparison with the two other resins. This study demonstrates the crucial role of resins in the optimal preservation of biological activity of carbohydrate residues in cryotechnically-processed cornea for electron microscopy.
Moulessehoul
S
S
Laboratoire de Recherches Ophtalmologiques, INSERM U.86, Hôtel-Dieu, Paris, France.
Hirsch
M
M
Pouliquen
Y
Y
D000818:Animals; D001665:Binding Sites; D002367:Ricinus communis; D003208:Concanavalin A; D003315:Cornea / Q000648:ultrastructure*; D005615:Freezing; D037102:Lectins / Q000378:metabolism*; D008854:Microscopy, Electron; D037121:Plant Lectins; D010947:Plants, Toxic; D016613:Plastic Embedding / Q000379:methods*; D011817:Rabbits; D014909:Wheat Germ Agglutinins
D037102:Lectins; D037121:Plant Lectins; C017707:Ricinus communis agglutinin-1; D014909:Wheat Germ Agglutinins; D003208:Concanavalin A