[Molecular basis of familial and sporadic forms of human prion diseases]

A role for B lymphocytes in anti-infective prion therapies?

The deposition of proteins in the form of amyloid fibrils and plaques is the characteristic feature of a number of neurodegenerative conditions affecting the nervous system. These disorders include prion and Alzheimer's diseases and are of enormous importance for public health. It has become apparent over the last 20 years that specificity and application in prion diseases' diagnostic and therapeutic situations are the most important considerations in designing strategies for the generation of antiprion antibodies. Specific antiprion therapeutics have been suggested and the establishment of the 'proof-of-principle' that the use of epitope-specific antiprion antibodies leads to indefinite delay of disease onset, has increased momentum for its use, although caution should be exerted prior to the application of new therapeutic strategies in a clinical set up. Furthermore, in vivo stimulation of immune-competent cells to specifically recognize and neutralize the abnormally folded isoform should also be pursued.

[Prion diseases in pediatrics]

Prion diseases are rare neurologic affections with a poor prognosis, occurring in both humans and animals. Creutzfeldt-Jakob disease (CJD) secondary to human extracted growth hormone treatment is the most frequent condition in pediatrics. In 1994, a new type of CJD (variant CJD) was described in young adults in the United Kingdom, only 10 years after the bovine spongiform encephalopathy epidemic, with recent works showing a direct relationship between the bovine epidemic and the human cases. An accumulation of a single protein called the prion protein (PrP) has been discovered in the brain in all of these cases, animal and human, leading to the hypothesis that a new infectious agent could proceed without any nuclear acid information; another hypothesis is that of a still unknown viral agent. The PRNP gene encoding for this PrP protein is well described: some mutations and a polymorphism in the 129th codon have been shown to be implicated in many cases of CJD. PrP is a ubiquitous protein, with yet unknown physiological function. There are still many questions to be answered: shall we expect new pediatric cases of variant CJD? Assuming that animal-human contamination is related to alimentation, are there other ways of contamination.