Proteomic Comparison of Amnion and Chorion and Evaluation of the Effects of Processing on Placental Membranes.

OBJECTIVE: The purpose of this study is to compare the growth factor and cytokine content found within the amnion and chorion layers and to determine the effects of dehydration on them.

MATERIALS AND METHODS: Placentas were collected from 5 to 6 consented donors following elective cesarean section, and 1-cm2 sections of either amnion or chorion were immediately stored at -80°C or dehydrated prior to -80°C storage until proteomic analysis. Signaling molecules from tissue samples were evaluated using quantitative multiplex proteomics microarrays, and data were analyzed based on a per cm2 basis and also on pg/mg of extracted protein for potency.

RESULTS: Fresh chorion contained more of some signaling molecules per cm2 compared with amnion. Specifically, the chorion contained significantly higher levels of adiponectin, APN, ANG-2, bFGF, EG-VEGF, HGF, IGF-1, PDGF-AA, PDGF-BB, TIMP-2, and TIMP-4. When samples were dehydrated, a significant drop in total growth factor and cytokine content was observed in both amnion and chorion samples with a loss of 51.1% ± 20.2% and 55.5% ± 37.3%, respectively. When evaluating the potency of fresh amnion and fresh chorion, there were similar levels of signaling molecules found with some exceptions. Amnion had significantly higher GAL-7, TGF-β1, and IL-1F5, and chorion had significantly more EG-VEGF, PDGF-BB, and TIMP-2.

CONCLUSION: The processing of placental membranes can have a dramatic effect on the total growth factor and cytokine load found within these tissues.