Preclinical regulatory validation of a 3-stage amniotic mesenchymal stem cell manufacturing protocol.
OBJECTIVE
Because of the 4 to 6-month interval between a diagnostic amniocentesis and birth, clinical application of amniotic mesenchymal stem cell (AMSC)-based therapies demands a 3-stage cell manufacturing process, including isolation/primary expansion, cryopreservation, and thawing/secondary expansion. We sought to determine the feasibility and cell yield of such a staged cell manufacturing process, within regulatory guidelines.


METHODS
Human AMSCs isolated from diagnostic amniocentesis samples (n = 11) were processed under Food and Drug Administration-accredited good manufacturing practice. Expanded cells were characterized by flow cytometry and cryopreserved for 3 to 5 months. Cell release criteria included more than 90% CD29+, CD73+, and CD44+; less than 5% CD34+ and CD45+; negative mycoplasma quantitative polymerase chain reaction (QPCR) and endotoxin assay; and at least 70% viability.


RESULTS
Isolation and ample expansion of AMSCs was achieved in 54.5% (6/11) of the samples. Early processing and at least a 2-mL sample were necessary for reliable cell manufacturing. Cell yield before cryopreservation was 223.2 +/- 65.4 x 10(6) cells (44.6-fold expansion), plus a 14.7 x 10(6)-cell backup, after 36.3 +/- 7.8 days. Cell viability postthaw was 88%. Expanded cells maintained a multipotent mesenchymal progenitor profile.


CONCLUSIONS
Human amniotic mesenchymal stem cells can be manufactured in large numbers from diagnostic amniocentesis, by an accredited staged processing, under definite procurement guidelines. These data further support the viability of clinical trials of amniotic mesenchymal stem cell-based therapies.
Department of Surgery, Children's Hospital Boston, Harvard Medical School, Boston, MA 02115, USA.
Shaun A
SA
Steigman
Myriam
M
Armant
Lucy
L
Bayer-Zwirello
Grace S
GS
Kao
Leslie
L
Silberstein
Jerome
J
Ritz
Dario O
DO
Fauza
D000649:Amniocentesis; D000653:Amniotic Fluid / Q000166:cytology*; D002469:Cell Separation / Q000379:methods / Q000592:standards; D002470:Cell Survival; D017690:Cell Transplantation / Q000592:standards*; D015925:Cryopreservation / Q000379:methods; D005260:Female; D005434:Flow Cytometry; D005865:Gestational Age; D017408:Guidelines as Topic; D006801:Humans; D059630:Mesenchymal Stem Cells; D011247:Pregnancy; D012680:Sensitivity and Specificity; D013048:Specimen Handling / Q000592:standards; D023822:Tissue Engineering / Q000592:standards*