## 4 Discussion  
As MSCs age, their properties gradually become compromised, including the properties of multilineage differentiation, homing, immune modulation, and wound healing [28; 29; 30]. Although it is well known that the number and function of BM-MSCs are affected by bone pathology, such as osteoarthritis or osteoporosis [31], no similar studies have been carried out on hAMSCs. In the present study, we have isolated hAMSCs obtained from aged and pre-eclamptic pregnant women accordingly, to established protocols for non-aged hAMSCs [8; 9; 32; 33]. To the best of our knowledge, this is the first time that a comparison of such sources of hAMSCs has been carried out concerning various phenotypic and functional parameters. Although the yield of hAMSCs from PE donors was lower than that for non-aged and aged women, also these donors gave sufficient numbers of hAMSCs to be expanded and cultured up to passage 5. If, however, we think that the advantage to comply on these ethical sources of MSCs is to yield a higher number of cells and avoid passaging that could lead to karyotypic abnormalities, this is a setback with pathological hAMSCs. Since the gestational age is similar between Group 1 and Group 2, and is even lower in Group 3, how could maternal factors influence the functional behavior of hAMSCs in terms of yield, viability, proliferation, and differentiation? It has been demonstrated that MSCs age in different organs [34], and that the increase in reactive oxygen species and epigenetic changes may underlie these alterations [31; 35; 36], that may well be at work also in aged placentas. Interestingly, [PERSON] et al. [37] determined by an immunohistochemistry study on MSCs in AM and Warthon's jelly of the umbilical cord, that CD105 and CD29 expression showed an inverse correlation with age, with the least expression in women aged older than 40 years. As concerning pre-eclampsia, this pathological condition is thought to be due to inadequate placental cytotrophoblast invasion, followed by widespread maternal endothelial dysfunction, which leads to placental hypoperfusion and ischemia [38; 39; 40]. The only report, to the best of our knowledge, that is concerned about the effects of PE on amniotic cells is the one by [PERSON] and colleagues [41], who found that surface marker profile of PE-hAMSCs was similar to that of normal hAMSCs, although the expression of co-stimulatory and immunomodulatory molecules was quantitatively different, perhaps as a response to the inflammatory infiltrates that have been detected in the amniotic membranes of pre-eclamptic placentas. Therefore, it is conceivable that alterations in the maternal and placental environment due to ageing and pathology may lead to a dysfunctional behavior (perhaps linked to heightened senescence) in cells belonging to the amniotic membrane, a hypothesis that has to be confirmed with further experiments. MSCs are characterized by a unique set of membrane molecules involved in adhesion and migration. CD29, which is also known as integrin \(\beta\)1, is highly expressed not only in MSCs but also in macrophages and plays an important role in cell migration [42; 43]. CD29 was found to be essential in the trafficking of BM-MSCs to the infarcted myocardium [44]. It is also the principal receptor for binding extracellular matrix (ECM) components, such as laminin, fibronectin, and collagens, and is involved in cell attachment [45]. It has been previously shown that integrin \(\beta\)1 is required for \begin{table}
\begin{tabular}{l c c} \hline \hline
**Time/Titanium Disk** & **Group 1** & **Group 2** \\ \hline
3 h/machined & 0.011 & 0.0358 \\
6 h/machined & 0.0049 & 0.0195 \\
24 h/machined & 0.0076 & 0.0130 \\
48 h/machined & 0.0087 & 0.0246 \\ \hline
3 h/sandblasted & 0.0013 & 0.0148 \\
6 h/sandblasted & \textless{}0.0001 & 0.0064 \\
24 h/sandblasted & 0.0007 & 0.0122 \\
48 h/sandblasted & 0.0005 & 0.0716 \\
72 h/sandblasted & 0.0199 & 0.0096 \\ \hline \hline \end{tabular}
\end{table}