Assuming that you are fixing fresh-frozen tissue sections: Tissue is autolysing.
Use Formalin for 10 mins or 1:1 acetone:alcohol for 10 mins. Imho, acetone is not a fixative..it's a delipidizer. 5 mins in that mixture is too short a time for the alcohol to be an effective coagulant fixer. However, a longer time in alcohol may well mask your Ag sites. I see this artefact in acetone fixed frozen sections, often. When immunostaining for MHCs in muscle, no fixation is required but, if DAPI/Hoechst is included....nuclear streaming will be seen. Always try several fixing fluids to get the best results on any new Ab. I may be wrong....happy to be corrected. Curious always, Carl _______________________________________________ Histonet mailing list Histonet@lists.utsouthwestern.edu http://lists.utsouthwestern.edu/mailman/listinfo/histonet
