Figure 1: Graphical description of:
a) Naturally occurring, a- helical based protein
b) Aberrant mis-folded, primarily ß-pleated sheet, ‘prion’ version.
CJD itself can be split into three distinct sub-types:
- Familial CJD. An inherited form of CJD in which offspring inherited a mutation within their genome causing the onset of CJD in later life.
- Sporadic CJD. Currently the most prolific of the human TSE’s with recorded incidences of around 0.5 – 1 person per million. Sporadic CJD is considered to occur when there is either a random mutation in the prion protein or its gene.
- Acquired CJD. A form of CJD that is by definition, obtained through a third party source. An example being variant CJD which is linked to the consumption of infected beef products, or iatrogenic CJD, where infection is induced inadvertently by the medical treatment or procedures or activity of a physician.
At the University of Southampton work on the elimination of iatrogenic CJD has been initiated.
Iatrogenic Creutzfeldt Jakob Disease (iCJD)
 As the pre-symptomatic incubation time for human TSE's is relatively unknown the risk of iatrogenic transmission is of great concern indeed if one considers that over 6 million operative procedures are carried out, annually. Then even if there is a relatively small number of the population harbouring the infection, the possibility of human-to-human transmission is very real.
Indeed 40 people have died in Britain since 1990 as a result of surgical procedures. Most had accidentally used contaminated growth hormone, and some received infected tissue to repair the protective membrane around the brain.
An official guideline for the safe handling, and use of suspected contaminated instruments was issued in 1998. These guidelines indicate that any instruments used on suspect CJD patients should be removed from circulation and quarantined immediately. To date there is no method of assessing these instruments for possible prion protein contamination. Surgical stainless steel instruments can be very expensive (e.g. £50,000) and some devices such as endoscopes, require specialised decontamination procedures.
Detecting the Undetectable?
 At the University of Southampton , the U.K. Department of Health have funded work to unlock the mysteries of whether surgical instruments that have been in contact with CJD victims are indeed contaminated. This work will assess both the requirement for instrument destruction and the efficacy of new cleaning methods.
To enable these tasks to be performed the University have collaborated with Best Scientific to produce a novel and unique microscopy technique which possesses the ability to rapidly and clearly display contamination on surgical instruments.
This, in conjunction with a bank of advanced detection procedure's, has provided the research group with the ability to 'label' and display the prion protein on surgical stainless steel.
Although at a relatively early stage, the work has shown itself to be highly sensitive, able to detect less than 1x10-12 g of protein.
 This work is ongoing and with the input of industrial partner Microgen Bioproducts Ltd, a leading diagnostic company. It is intended that a standard, easily applicable detection method can be developed, and the problem of whether surgical tools are contaminated or not, eliminated.
The work has been highly successful so far, and has enabled the research group to lodge several patents in relation to it.
Vcjd research microscope in containment cabinet 3
Further Information on TSE's
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