The Do's and Don'ts of
Taking Human Brain Tissue into the Classroom
Paul F. Aravich, Cynthia Phelps and William Guido, SFN Committee on
Neuroscience Literacy, SFN Abstracts, 26:38, 2000.
Address correspondence regarding this report to Dr. Aravich at: Aravicpf@evms.edu
The "Do's and don'ts" of taking human brain tissue into the classroom or
to the public requires The Rs: Respect, Sensitivity, Safety.
A. Respect
- Instill care, respect and dignity for the donor before any tissue is
handled. (The sign outside one gross anatomy laboratory reads, "here the
dead teach the living").
- Set the example for students. Joking or disrespectful conduct should
not be tolerated.
- Set the ground rules before displaying or handling tissue.
- Designate an area or table where the tissue is displayed.
- Practice proper crowd control.
B. Sensitivity
- Exercise cultural competency and sensitivity at all
times. There are
well-established belief systems and cultural barriers associated with
organ donations (7,8). While most of the world's major religious
traditions (e.g., Protestantism, Catholicism, Judaism, Greek Orthodox,
Islam, Buddhism, and Hinduism) do not prohibit organ donation (9),
cultural, spiritual and religious traditions should always be kept in
mind.
C. Safety
- Deactivate potential prions such as Creutzfeldt-Jakob
Disease (CJD) prion before taking tissue to the public. Prions are not
killed by formalin fixation (see 1, 2, 4). High concentrations of phenol
or formic acid deactivate them (see 1, 2, 4). However, formic acid makes
the tissue brittle and may not be suitable for whole brains. Other
deactivating agents include 1N sodium hydroxide, 4.0 M guanidinium
hydrochloride, and household bleach (sodium hypchlorite, > 2% free
chlorine) (4). Immerse formalin-fixed brains in household bleach or
liquefied phenol (90% w/w; Fisher Scientific, Pittsburgh, PA) for 2-3 days
to deactivate potential prion that may occupy the brain surface. Special
brain dissections and brain slices should be treated in the same fashion
prior to public display so that all surface areas are deactivated.
Brain surfaces prepared in this fashion should have essentially no risk
of prion disease. Otherwise, the risk of CJD prion in 6 European
populations between 1993-1995 was 0.71 cases per million people (5). If
it is assumed that the average number of people killed by lightening in
the United States each year is 20.1 deaths per million (6), the
probability of getting killed by lightening is 28 times greater than the
probability of contacting a body with CJD. Nonetheless, even though the
bloodborne pathogens standard of the US Occupational Safety and Health
Administration (OSHA) (3) does not apply to fixed tissue unless it is
infected with the human immunodeficiency virus (HIV) or the hepatitis B
virus (HBV), deactivate potential prions prior to public display.
- Minimize formalin (and phenol) exposure. Formalin is toxic and a
potential carcinogen. Immerse all phenol-treated, formalin-fixed brains
for two or three days in a few changes of dilute ethanol (20% v/v).
Tissue fixation can be maintained for an extended period of time by
leaving the brain in the ethanol. To further minimize chemical exposure,
place the brains in water before showing them to the public.
- Minimize spills during transportation. This can be done by placing
brains in double containers (e.g., containers within plastic bags). Bag
brains in zip-locked bags to provide an extra measure of safety.
- Display tissue in well-ventilated room.
- Minimize skin contact. Gloves (latex or
rubber) should be worn at all times by all parties to avoid skin contact
(4). Very small children require adult supervision to maintain this
safety standard. Tissue contact with clothing should also be avoided.
Show students how to put on and remove gloves. Skin punctures are highly
unlikely in brain demonstrations that do not involve sharp objects. In
the unlikely event of such a puncture, swab the affected area with 1N
sodium hydroxide for 5 minuets then rinse with a large amount of water
(4).
- Instruct students not to touch others or themselves while handling
brains. "Don't touch your face."
- Never allow lay people to handle tissue without supervision.
- Minimize splashing/spraying. This can be achieved by blotting the
tissue before public demonstrations and by displaying/handling tissue over
a catch basin or absorbent material.
- Follow OSHA Safe Laboratory Practices. Prohibit eating, drinking,
smoking, applying cosmetics or lip balm, and handling of contact lenses in
the immediate area of the brain display (3).
- Note taking should be done away from display area.
- Dispose of waste properly. Treat all tissue scraps as biohazard
(double bagging and incineration). When decontaminated brains are used,
waste (paper, gloves, etc.) can be placed in normal trash.
Formalin-contaminated waste must be disposed of through a chemical safety
office.
- Decontaminate surfaces. Household bleach will inactivate prions when
left on the surface for a minimum of 15 minutes (2). When possible, place
the tissue on absorbent, disposable materials that do not contaminate
surface areas. Absorbent, plastic-lined material, such as absorbent lab
bench pads or Kendall Disposable Underpads, are ideal for this purpose.
- Instruct all parties to wash their hands thoroughly in soap and water
after handling tissue.
- Visit the Committee on Neuroscience
Literacy page, Neuroscience for
Kids or BrainSurf for educational
resources to enhance your outreach efforts.
- Consult the other educational resources provided by the SFN.
- Have fun! And remember the Rs: Respect, Sensitivity, and Safety.
Acknowledgements: The assistance of LaMarr G. Beuchler, Director of
Environmental Health & Safety/Radiation Safety, Eastern Virginia Medical
School, Norfolk, VA, is greatly acknowledged, as is the assistance of
Shaunak Deepak, Virginia Governor's School for Science and Technology, New
Horizons Regional Education Center, Hampton, VA.
References:
- Brown P, Wolff A, and Gajdusek DC. A simple and effective method for
inactivating virus infectivity in formalin-fixed tissue samples from
patients with Creutzfeldt-Jakob disease. Neurology 1990 40:887-890.
- Crain, BJ. CAP Today, College of American Pathologists, January 1996.
- OSAH Regulations (Standards - 29 CFR). Bloodborne pathogens. Standard
Number: 1910.1030 Occupational Safety and Health Administration, US
Department of Labor.
- Prions. Biosafety in Microbiological and Biomedical
Laboratories. Centers for Disease Control and Prevention, National
Institutes of Health, US Department of Health and Human Services, May,
1999 pp 134-147.
- Will RG, Alperovitch A, Poser S, Pocchiari M, Hofman A, Mitrova E, de
Silva R, D'Alessandro M, Delasnerie-Laupretre N, Zerr I, van Duijn
C. Descriptive epidemiology of Creutzfeldt-Jakob disease in six European
countries, 1993-1995. EU Collaborative Study Group for CJD. Ann Neurol
1998 Jun;43(6):763-7
- Daily Newsbulletin, Los Alamos National Laboratory (June 15,
1998. http://lanl.gov/orgs/pa/News/o61598text.html
- Marshall PA, Daar AS. Cultural and psychological dimensions of human
organ transplantation. Ann Transplant 1998;3(2):7-11.
- Callender C, Burston B, Yeager C, Miles P. A national minority
transplant program for increasing donation rates. Transplant Proc 1997
Feb-Mar;29(1-2):1482-
- Religious Perspectives. Tissue Donation and Postmortem Human Brain
Research. Harvard Brain Tissue Resource Center. Stephen L. Vincent,
Ph.D., Associate Director.