Transplantation into the central nervous system: a therapy of the future.

Grafts in the central nervous system probably work by a number of mechanisms. Our understanding of these mechanisms and how they might be employed to treat neurological disease is still elementary. As the sophistication in the functioning of the grafts increases, so does the sophistication required in the preparation of the tissues for grafting. Similarly, new techniques will be required to place the grafts in a manner advantageous to both graft survival and function and that carries minimal risk to the host. There is still much basic science investigation that must be performed, but basic science investigations without clinical input frequently go off track. Animal work has never completely solved medical problems, but it is also true that clinical investigations without solid scientific background are likely to fail. Clinical investigations must proceed in centers that have the expertise to evaluate these clearly experimental procedures until the technique is sufficiently mastered to allow widespread use. Neither our colleagues nor the public will long tolerate unmerited or inappropriate surgical procedures.