The description of a microencapsulation procedure for Wharton's jelly mesenchymal stem cells (WJMSCs) is reported. The applied method is based on the generation of monodisperse droplets by a vibrational nozzle. An ionic alginate encapsulation procedure was utilized for the microbeads hardening. Different experimental parameters were analyzed, including frequency and amplitude of vibration, polymer pumping rate, and distance between the nozzle and the gelling bath. The produced barium-alginate microbeads were characterized by excellent morphological characteristics as well as a very narrow size distribution. The microencapsulation procedure did not alter the morphology and viability of the encapsulated WJMSCs. In addition, the current paper reports the functional properties in terms of secretive profiles of both free and encapsulated WJMSCs. The analyzed factors were members of the family of interleukins, chemokines, growth factors, and soluble forms of adhesion molecules. These experiments showed that despite encapsulation, most of the proteins analyzed were secreted both by the free and encapsulated cells, even if in a different extent. In conclusion, the described encapsulation procedure represents a promising strategy to utilize WJMSCs for possible in vivo applications in tissue engineering and biomedicine.

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Background. Different surgical variables are assumed to play a role in postoperative course after lower third molar extraction. The aim of study was to assess whether flap design and duration of surgery can influence acute postoperative symptoms and signs after lower third molar extraction. Methods. Twenty-five patients scheduled for lower third molar extraction were included in this study and randomly assigned to two groups in terms of flap design: group A (envelope flap) and group B (triangular flap). Swelling and trismus were assessed before and after surgery on days 0, 2 and 7. Pain was assessed for seven days after surgery. Maximum postoperative pain was chosen as the main outcome variable. ANOVA was used to assess differences between the groups regarding maximum postoperative pain, trismus and swelling at 2- and 7-day intervals. Pearson's correlation coefficient was used to assess correlation between duration of surgery and postoperative symptoms and signs. Results. No significant difference was found between the two flap designs for any postoperative symptoms and signs. The duration of surgery was found to be correlated with both trismus (r = -0.44, P = 0.04) and swelling (r = 0.59, P = 0.004) as assessed 2 days after surgery. No associations were found between duration of surgery and maximum postoperative pain and trismus and swelling at 7-day interval. Conclusion. Within the limits of the present study, the duration of surgery, and not the flap design, affected the acute postoperative symptoms and signs after lower third molar extraction.

BackgroundTo propose a novel composite outcome measure (COM) for periodontal regenerative treatment of intraosseous defects.MethodsCOM is based on the combination of clinically relevant clinical attachment level (CAL) gain (≥3 mm) and pocket closure (post‐surgery probing depth [PD] ≤ 4 mm). Treatment was regarded as successful when a clinically relevant CAL gain was associated with pocket closure, and failing when either clinically relevant CAL gain and pocket closure were not achieved. The effect of the different regenerative treatments was both collectively and separately evaluated according to COM in a defect cohort accessed by Single Flap Approach (SFA).ResultsIn the entire study cohort, the procedure resulted in a 6‐month CAL gain of 3.7 ± 1.9 mm, which was clinically relevant in 71.8% of patients. Six‐month residual PD was 3.7 ± 1.1 mm, with pocket closure recorded in 79.6% of patients. COM revealed a successful treatment in 60 patients (58%), and a treatment failure in 7 patients (7%). Mean CAL gain was clinically relevant for each treatment, whereas the residual PD values were consistent with pocket closure for the majority of treatment options. However, when COM was used to rate the treatment outcome of each procedure, it appeared that a successful treatment ranged from 41.5% to 77.5%, whereas treatment failure varied from 3% to 15% for different treatments.ConclusionsCompared to single probing measurements, COM seems (1) more accurate in capturing the overall benefit of the regenerative procedure and (2) to better identify which factor (CAL gain, residual pocket) mainly contributed to determine a treatment failure.

The pathways that control mesenchymal stem cells (MSCs) differentiation are not well understood, and although some of the involved transcription factors (TFs) have been characterized, the role of others remains unclear. We used human MSCs from tibial plateau (TP) trabecular bone, iliac crest (IC) bone marrow and Wharton’s jelly (WJ) umbilical cord demonstrating a variability in their mineral matrix deposition, and in the expression levels of TFs including Runx2, Sox9, Sox5, Sox6, STAT1 and Slug, all involved in the control of osteochondroprogenitors differentiation program. Because we reasoned that the basal expression level of some TFs with crucial role in the control of MSC fate may be correlated with osteogenic potential, we considered the possibility to affect the hMSCs behaviour by using gene silencing approach without exposing cells to induction media. In this study we found that Slug-silenced cells changed in morphology, decreased in their migration ability, increased Sox9 and Sox5 and decreased Sox6 and STAT1 expression. On the contrary, the effect of Slug depletion on Runx2 was influenced by cell type. Interestingly, we demonstrated a direct in vivo regulatory action of Slug by chromatin immunoprecipitation, showing a specific recruitment of this TF in the promoter of Runx2 and Sox9 genes. As a whole, our findings have important potential implication on bone tissue engineering applications, reinforcing the concept that manipulation of specific TF expression levels may elucidate MSC biology and the molecular mechanisms, which promote osteogenic differentiation.

Wharton's jelly from the umbilical cord is a noncontroversial source of mesenchymal stem cells (WJMSCs) with high plasticity, proliferation rate and ability to differentiate towards multiple lineages. WJMSCs from different donors have been characterized for their osteogenic potential. Although there is large evidence of WJMSCs plasticity, recently scientific debate has focused on MSCs selection, establishing predictable elements to discriminate the cells with most promising osteoprogenitor cell potential.In the present study a comparative study between the presence of osteoblastic markers and different parameters that pertain to both the newborn and the mother was performed. Umbilical cords were collected after all patients signed the informed consent and local ethical commettee approved the study. Obstetric parameters, including baby's gender and birth weight, mother's age at delivery, gestational stage at parturition and mode of delivery were examined. After characterization and expansion, WJMSCs were analyzed for two osteoblastic markers, alkaline phosphatase (ALP) activity, and the expression level of RUNX-2 transcription factor, and for their ability to deposit mineralized matrix after osteogenic induction.We found that osteoblastic potential was not influenced by baby's gender and mode of delivery. On the contrary, the highest degree of osteoblastic potential has been shown by WJMSCs with RUNX-2 high basal levels, selected from umbilical cords of the heaviest term babies.Even if further evaluation is required, our hypothesis is that our findings may help in selecting the optimal umbilical cord donors and in collecting high potential Wharton's jelly-derived osteoprogenitors efficiently.

The development and the optimization of novel culture systems of mesenchymal osteoprogenitors are some of the most important challenges in the field of bone tissue engineering (TE). A new combination between cells and extracellular matrix (ECM)-scaffold, containing ECM has here been analyzed. As source for osteoprogenitors, mesenchymal stem cells obtained from human umbilical cord Wharton's Jelly (hWJMSCs), were used. As ECM-scaffold, a powder form of isolated and purified porcine urinary bladder matrix (pUBM), was employed. The goals of the current work were: (1) the characterization of the in vitro hWJMSCs behavior, in terms of viability, proliferation, and adhesion to ECM-scaffold; (2) the effectiveness of ECM-scaffold to induce/modulate the osteoblastic differentiation; and (3) the proposal for a possible application of cells/ECM-scaffold construct to the field of cell/TE. In this respect, the properties of the pUBM-scaffold in promoting and guiding the in vitro adhesion, proliferation, and three-dimensional colonization of hWJMSCs, without altering viability and morphological characteristics of the cells, are here described. Finally, we have also demonstrated that pUBM-scaffolds positively affect the expression of typical osteoblastic markers in hWJMSCs.

For the first time human mesenchymal stem cells obtained from periodontal ligaments encapsulated in alginate microbeads were cultured in a bioreactor system. This combination could represent a promising strategy to create a cell-based smart system with enhanced osteogenic potential useful for many different dental applications.