Localization of GFP in frozen sections from unfixed mouse tissues: immobilization of a highly soluble marker protein by formaldehyde vapor.
Green fluorescent protein (GFP) and its variants, such as enhanced GFP (EGFP), have been introduced into mammalian cells by transgenes, e.g., to distinguish donor from host cells after transplantation. Free GFP is extremely soluble and leaks out from liquid-covered cryostat sections so that fixation of whole organs before sectioning has been mandatory. This precludes the analysis of serial sections with respect to fixation-sensitive enzyme activities and antigens. We describe here a vapor fixation for sections from unfixed cryostat blocks of tissue that allows unrestricted enzyme and immunohistochemistry on adjacent sections, as demonstrated for cross-striated muscle and other tissues from EGFP transgenic "green mice" and for a transplantation experiment.
Jockusch
Harald
H
Developmental Biology and Molecular Pathology, University of Bielefeld, Bielefeld, Germany. h.jockusch@uni-biefeld.de
Voigt
Sylvana
S
Eberhard
Daniel
D
D000818:Animals; D005404:Fixatives; D005557:Formaldehyde; D005629:Frozen Sections; D049452:Green Fluorescent Proteins; D008164:Luminescent Proteins / Q000378:metabolism*; D051379:Mice; D008822:Mice, Transgenic; D009928:Organ Specificity; D016707:Tissue Fixation; D014835:Volatilization
D005404:Fixatives; D008164:Luminescent Proteins; D049452:Green Fluorescent Proteins; D005557:Formaldehyde