title: Evaluation of zinc salt based fixatives for preserving antigenic determinants for immunohistochemical demonstration of murine immune system cell markers.
abstract: Conventional aldehyde based fixatives produce good morphological preservation. However, owing to their cross-linking mechanism of action, epitope loss may occur during fixation compromising the tissue for subsequent immunohistochemical (IHC) analysis. IHC is an important tool for characterizing antigen, cytokine and cytomorphological markers. The increasing use of mouse models for study of pathogenesis has highlighted the need to investigate alternative fixatives. In the study reported here, tissue samples from RIII mice with immune mediated lesions, Mycobacterium bovis infected mice, and uninfected control mice were fixed in either zinc salt fixative or buffered formalin, then tested for IHC using a panel of antibodies (CD3, CD4, CD8, CD45, CD54, F4/80, Interferon-gamma and MIP2). Zinc salt fixation preserved processing-sensitive murine cell markers (CD4, CD8 and CD54) and improved the intensity of immunolabeling for CD45, F4/80 and CD3. Buffered formalin failed to preserve any of the processing-sensitive murine epitopes for demonstration by subsequent IHC.
authors.affiliation: Departments of Pathology, Veterinary Laboratories Agency, New Haw, Addlestone, Surrey, KT15 3NB, United Kingdom.
authors.forename: D J
authors.initials: DJ
authors.lastname: Hicks
authors.forename: L
authors.initials: L
authors.lastname: Johnson
authors.forename: S M
authors.initials: SM
authors.lastname: Mitchell
authors.forename: J
authors.initials: J
authors.lastname: Gough
authors.forename: W A
authors.initials: WA
authors.lastname: Cooley
authors.forename: R M
authors.initials: RM
authors.lastname: La Ragione
authors.forename: Y I
authors.initials: YI
authors.lastname: Spencer
authors.forename: A
authors.initials: A
authors.lastname: Wangoo
mesh_terms: D000818:Animals; D000954:Antigens, Surface / Q000032:analysis*; D016516:CD4-CD8 Ratio; D002712:Chlorides; D004195:Disease Models, Animal; D005404:Fixatives / Q000737:chemistry*; D007150:Immunohistochemistry / Q000379:methods*; D018799:Intercellular Adhesion Molecule-1 / Q000032:analysis; D051379:Mice / Q000276:immunology* / Q000382:microbiology; D009163:Mycobacterium bovis / Q000276:immunology; D014376:Tuberculosis / Q000276:immunology; D019345:Zinc Acetate; D017967:Zinc Compounds
chemical_list: D000954:Antigens, Surface; D002712:Chlorides; D005404:Fixatives; D017967:Zinc Compounds; D018799:Intercellular Adhesion Molecule-1; C016837:zinc chloride; D019345:Zinc Acetate