Preterm birth one of the biggest complications in Obstetrics and is the case of life-long morbidities or even mortality of newborns. With advances in fetal therapy, the occurrence of operation-induced failures of fetal membranes (FM) ending in preterm birth is increasing. Responsible for this adverse outcome are the created defects in the FM that do not spontaneously heal. Treatments aiming at the preventive closure these defects have not been successful so far. Understanding the biology of the FM biology at the time of intervention would be essential to develop regeneration-promoting strategies.
Term and pre-term amnion biopsies were collected after caesarian section at 36 to 37 gestational weeks (GW) and open fetal surgeries for the treatment of fetuses with spina bifida (GW 21 to 23). Protein extraction was optimized by undertaking a systematic shotgun proteomics approach using a high pH reversed-phase liquid chromatography (RPLC) sample fractionation followed by low pH liquid chromatography-mass spectrometry analysis (LC-MS/MS). Isolated FM cells and tissues were encapsulated in synthetic poly(ethylene glycol) PEG-based biomaterials, treated with selected stimulants and the proliferation and migration of cells was followed.
Over 5000 proteins were identified in the term human amniotic membrane. Differential expression of extracellular matrix (ECM) components were identified in preterm and term amnion. Selected growth factors and ECM components were shown to modify the growth and migration of amnion cells.
The high number of identifications demonstrates for the first time the high complexity of this fetal tissue. We identified several core ECM and ECM-associated proteins that can modify the regeneration of the amnion. Integrating the identified signals into new hybrid biomimetic materials could be promising for the treatment of FM defects.
To our knowledge, this is the first time that the human amnion protein composition of preterm amnion has been evaluated in a global proteomics approach. This knowledge will instruct the development of therapies for the prevention of preterm birth."