Diaminobenzidine cytochemistry in cryoultramicrotomy for the detection of peroxidases

Wolf D. Kuhlmann, A. Viron


Immunocytochemistry SFB 136, Institut für Nuklearmedizin, Deutsches Krebsforschungszentrum
Im Neuenheimer Feld 280, D-6900 Heidelberg, Germany
Institut de Recherches Scientifiques sur le Cancer, Villejuif, France
Rat erythrocytes and lymphoid cells were fixed by glutaraldehyde and encapsulated in bovine serum albumin plus rabbit IgG globulins for cryo-ultramicrotomy. A technical procedure is described by which endogenous peroxidases of erythrocytes in ultrathin frozen sections were detected by hydrogen peroxide and diaminobenzidine as hydrogen donor. Modifications of this classical cytochemical procedure proved also useful in cryo-ultramicrotomy for immunoperoxidase labeling of antigenic determinants in rabbit IgG globulins which have been cross-linked within the supporting matrix of cells.