Background: Myometrial contractions of the non-pregnant uterus induce intra-uterine peristaltic flows. We developed a tissue engineered endometrial barrier to study the effect of peristaltic wall shear stresses (PWSS).
Methods: Endometrial epithelial cells (EEC) and myometrial smooth muscle cells (MSMC) were co-cultured in custom-designed wells that enable mechanobiology experiments. The SMSC were cultured first on a collagen coated PTFE synthetic membrane, and then, the EEC were cultured on the MSMC that were coated with Matrigel to simulate the stromal tissue. In order to induce PWSS on the in vitro model we developed a new experimental setup. A 3D printed belt with a sinusoidal periodic shape induced elastic wall movements in a flow chamber equipped with 3 well bottoms with the endometrial model. We also conducted a finite element analysis with the ADINA software in order to compute the time dependent PWSS exerted on top of the in vitro endometrial model at the bottom of the flow chamber. Then, we exposed the in vitro biological model to peristaltic flows for 30 and 60 minutes. After the test, the cells were stained for immunofluorescence studies.
Results: Using confocal imaging we verified that the 3D co-culture model is actually mimicking the intrauterine structure with specific and non-specific antibodies. WE observed variations in the cytoskeletal structure after exposure to PWSS for 60 minutes, but not after 30 minutes.
Conclusion: A tissue-engineered endometrial was built for the first time and subjected to in vitro peristaltic flows to mimic in vivo uterine peristalsis.