Improvement of a post-embedding immunogold labeling method for osmicated tissue / 基础医学与临床

ABSTRACT

Objective To establish a new post-embedding immunoelectron microscopy method for localization of protein antigens in central nervous system using colloidal golds as probes.Methods Rat brain tissue sections were fixed with osmium-ferrocyanide mixture.Free floating frozen sections were collected to determine the retrievability of antigens by sodium metaperiodate(NaIO_(4)).Then the best concentration of NaIO_(4) for maximal antigen retrieval was determined on hydrophilic Technovit 7100 resin-embedded semithin sections.Finally,the corresponding antigen was labeled with colloidal golds on ultrathin sections.Results NaIO_(4) showed different retrieving effects on different antigens;to those antigens that could be effectively retrieved by NaIO_(4),low concentration of NaIO_(4)could realize antigen retrieval;EM microscopy showed that ultrathin sections treated by low concentration of NaIO_(4) allowed higher density of colloidal gold labeling without apparently compromising the ultrastructures of tissues.