POSTSCRIPT: In an email to me regarding this article, Dr. Alafuzoff wanted to add this: "[A]s new antibodies are produced almost monthly and some of them work better than others on archived material (ex. synuclein), maybe we all working in this field should try out new antibodies at regular intervals."
I discuss issues pertaining to the practice of neuropathology -- including nervous system tumors, neuroanatomy, neurodegenerative disease, muscle and nerve disorders, ophthalmologic pathology, neuro trivia, neuropathology gossip, job listings and anything else that might be of interest to a blue-collar neuropathologist.
Friday, January 15, 2010
Can that brain you left in storage since 1996 still be assessed immunohistochemically?
The current issue of the Journal of Neuropathology and Experimental Neurology features an article about the effect of prolonged fixation time on the immunoreactivity of brain tissue being assessed for neurodegenerative disease. Dr. Irina Alafuzoff from Uppsula University in Sweden is the senior author on this study which looked at 20 post-mortem brains to determine whether prolonged fixation time has a deleterious effect on typical immunohistochemical stains used for neurodegenerative disease diagnosis. A panel of commercial antibodies to amyloid-[beta], ubiquitin, p62/sequestosome, tau, and [alpha]-synuclein was assessed using tissue microarray with several antigen retrieval methods. Short-term fixation was defined as a time period of up to 70 days before paraffin embedment. Long-term fixation was defined as 71 days to 14 years in formalin. The bottom line is that brains that are stored in 10% formalin for periods far exceeding a decade do indeed lose some immunoreactivity. But with proper antigen retrieval techniques (which are outlined in detail in the article) immunoreactivity can be maintained in these long-fixed tissues. Keep this article in mind to avoid false-negative results in brain autopsy specimens that have fixed for prolonged periods of time.
Subscribe to:
Post Comments (Atom)
Neuropathology Blog is Signing Off
Neuropathology Blog has run its course. It's been a fantastic experience authoring this blog over many years. The blog has been a source...
-
Shannon Curran, MS with her dissection Shannon Curran, a graduate student in the Modern Human Anatomy Program at the University of Co...
-
Last summer I put up a post about a remarkable whole nervous system dissection that was carried out at the University of Colorado School of ...
No comments:
Post a Comment