Pendant le Congrès Myologie 2005,
le Pr Lacau Saint-Guilly a présenté le jeudi 12 mai 2005, lors
du symposium parallèle "Transfert de myoblastes et applications cliniques"
une communication dont le titre est : "Greffe autologue de myoblastes dans les
muscles pharyngés de patients OPMD".
> Texte de sa communication en anglais :
PROTOCOL OF AUTOLOGOUS MYOBLAST GRAFTS IN THE PHARYNGEAL MUSCLES TO CORRECT
DYSPHAGIA IN PATIENTS WITH OCULO-PHARYNGEAL MUSCULAR DYSTROPHY
Oculo-pharyngeal muscular dystrophy (OPMD), is characterized by the selective
impairement of the upper esophageal sphincter (UES) and of the pharyngeal
muscles resulting in dysphagia. The most common treatment for dysphagia is a UES
myotomy which however does not prevent the progressive degradation of the
pharyngeal muscles which sustain the pharyngeal propulsion.
A protocol of
autologous myoblast grafts in the pharyngeal muscles has been initiated in June
2004 to correct dysphagia in patients with oculo pharyngeal muscular dystrophy,
in accordance with the French legislation on ethical rules. Our aim is to
improve both swallowing and the contractile deficit generated by the dystrophic
pharyngeal muscles. This model of cellular therapy has been tested through a
preclinical study performed in normal dogs, allowing to validate the procedure
and its safety, as well as to study the survival of the myoblasts grafted in the
pharyngeal muscles.
The clinical trial includes patients who exhibited both
signs of decreased pharyngeal propulsion and UES dysfunction. Biopsy of
unaffected muscles (quadriceps and sterno-cleido-mastoid muscle) was performed
to select the donor muscle. Then a sample of the chosen muscle was taken one
month prior to the autotransplantation, and amplification of myoblasts was
carried out in culture. The surgery consists in both a UES myotomy and
injections of myoblasts above the site of myotomy, in the pharyngeal dystrophic
muscles.
Results of the graft are evaluated by analysing the swallowing
efficacy and the pharyngeal propulsion which is pre and post-operatively studied
by videofluoroscopy swallowing study and videofiberoscopy of swallowing, and
also by a questionnaire and quantitative analysis, performed at one month
post-surgery, and every six months during two following years. As for today, 6
patients have already been enrolled in the study and 4 of them underwent the
complete grafting process. No adverse effect has been observed.
This protocol
may both improve the long-term treatment of the swallowing disorders and
decrease life-threatening complications induced by aspiration and weight loss,
due to the decreased pharyngeal propulsion.