Amniotic Membrane Implantation In Mucopolysaccharidosis

Amniotic membrane implantation has been performed as an approach to enzyme replacement in mucopolysaccharidosis (MPS). The rationale for this study is based on the findings that cultured amniocytes secrete lysosomal enzymes and that amnion membranes are non-immunogenic. 19 patients (MPS I,II,III), ages 3 to 16 yr., have had implantation of human amniotic membranes obtained from elective repeat C-sections. The subcutaneous implants in the abdominal wall have been well tolerated with follow-up between 4 to 12 mo. The effects of amniotic membrane implantation on the clinical status of the patients was evaluated by comparing the following studies pre- and 6 mo. post-implantation: EKG, echocardiography, head and liver CT, liver/spleen scan, skeletal survey, fundus exam, electroretinography, audiological assessment, auditory brain stem response and joint range of motion. Objective clinical improvement was noted as an increased range of motion in 3 of 18 patients. Biochemical analysis demonstrated no change in serum or WBC enzyme activity. Urinary GAG transiently decreased in 2 of 10 patients with levels returning to pre-treatment range at 6 mo. post implantation. Biopsy of the implantation site at 6 mo. post implantation demonstrated a foreign body reaction with no evidence of amnion tissue. Amniotic membrane implantation appears to have limited success as a means of enzyme replacement.