Dix ans de traitement substitutif de maladies neurodégénératives par greffe de neurones fœtaux : un bilan positif mais des interrogations sur l’avenir

Abstract

Fetal neural allografts have already proven their therapeutic value in several hundreds of patients with Parkinson's disease, and have very recently provided promising results for patients with Huntington's disease in our center. Fetal neurons integrate readily into the neural parenchyma of the adult hosts, differentiate into mature neurons and substitute, anatomically and functionally for lost host neurons. Notable clinical improvements have been obtained using this procedure. Nevertheless, a major obstacle hampers the development of the technique, that provoked by the logistic difficulty in retrieving and preparing the tissue. Indeed, this requires, for each surgical session, the organization of a chain of expertise which cannot be taken up by an external provider (e.g. a biotech company). This is difficult to organize outside of specialized research centers. The future of the technique relies, therefore, upon the design of alternative sources of tissue. Two different ways are currently explored very actively, namely xenografting of neurons of porcine origin and human stem cells, in particular derived from ES cells. In both cases, but in different ways, the goal of both techniques is to allow the organisation of cell banking systems, relieving the constraints of obtaining the collaboration of specialized obstetricians and biologists. Obstacles foreseen for these two alternative ways of fetal neurons to be are identified and research laboratories are actively exploring ways to overcome them.