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Mesenchymal stromal/stem cells (MSCs) demonstrate immunomodulation capacity that has been implicated in the reduction of graft-versus-host disease. Accordingly, we herein investigated the capacity of MSCs derived from several tissue sources to modulate both proinflammatory (interferon [IFN] γ and tumor necrosis factor [TNF] α) and immunosuppressive cytokines (transforming growth factor [TGF] β and interleukin [IL] 10) employing xenogeneic human MSC-mixed lymphocyte reaction (MLR) test. Bone marrow-derived MSCs showed higher self-renewal capacity with relatively slow proliferation rate in contrast to adipose-derived MSCs which displayed higher proliferation rate. Except for the lipoprotein gene, there were no marked changes in osteogenesis- and adipogenesis-related genes following in vitro differentiation; however, the histological marker analysis revealed that adipose MSCs could be differentiated into both adipose and bone tissue. TGFβ and IL10 were detected in adipose MSCs and bone marrow MSCs, respectively. However, skin-derived MSCs expressed both IFNγ and IL10, which may render them sensitive to immunomodulation. The xenogeneic human MLR test revealed that MSCs had a partial immunomodulation capacity, as proliferation of activated and resting peripheral blood mononuclear cells was not affected, but this did not differ among MSC sources. MSCs were not tumorigenic when introduced into immunodeficient mice. We concluded that the characteristics of MSCs are tissue source-dependent and their in vivo application requires more in-depth investigation regarding their precise immunomodulation capacities.

The present study compared the potential of porcine bone marrow mesenchymal stem cells (pBMSCs) at different passages as nuclear transfer (NT) donors and the developmental efficiency of NT embryos from donor cells transfected with/without Oct4 and Sox2. Early-passage pBMSCs showed higher proliferation and expression of Oct4 and Sox2 and differentiation potential into mesenchymal lineages than middle- and late-passage pBMSCs. Cleavage rate did not differ among pBMSCs at different passages, but NT embryos with early-passage pBMSCs and middle-passage pBMSCs transfected with Oct4 (Oct4-pBMSCs) had significantly (p<0.05) higher blastocyst development than those with middle-passage pBMSCs. The incidence of apoptotic bodies in NT blastocysts from late-passage pBMSCs and Sox2-transfected middle-passage pBMSCs (Sox2-pBMSCs) was significantly (p<0.05) higher than others. The transcriptional levels of Oct4, Sox2, Nanog, Cdx2, Dnmt3a, and Igf2r genes were significantly (p<0.05) higher in Oct4- and Sox2-pBMSCs NT embryos. Middle-passage pBMSCs NT embryos revealed lower transcriptional levels of Bcl2 than others, except Sox2-pBMSCs NT embryos. The transcriptional level of Bax increased gradually in NT embryos derived from pBMSCs following extended passages and was significantly (p<0.05) higher in Sox2-pBMSCs NT embryos. Our results demonstrated that early-passage pBMSCs are more potent in expressing transcription factors and displayed higher differentiation ability, and middle-passage pBMSCs transfected with Oct4 improved the developmental efficiency of NT embryos, suggesting that high Oct4 expression cells are more efficient as NT donors.

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Lately, in orthodontic treatments, the use of transparent aligners for the correction of malocclusions has become prominent owing to their intrinsic advantages such as esthetics, comfort, and minimal maintenance. Attempts at improving upon this technology by varying various parameters to investigate the effects on treatments have been carried out by several researchers. Here, we aimed to investigate the biomechanical and clinical effects of aligner thickness on stress distributions in the periodontal ligament and changes in the tooth’s center of rotation. Dental finite element models comprising the cortical and cancellous bones, gingiva, teeth, and nonlinear viscoelastic periodontal ligaments were constructed, validated, and used together with aligner finite element models of different aligner thicknesses to achieve the goal of this study. The finite element analyses were conducted to simulate the actual orthodontic aligner treatment process for the correction of malocclusions by generating pre-stresses in the aligner and allowing the aligner stresses to relax to induce tooth movement. The results of the analyses showed that orthodontic treatment in lingual inclination and axial rotation with a 0.75 mm-thick aligner resulted in 6% and 0.03% higher principal stresses in the periodontal ligament than the same treatment using a 0.05 mm-thick aligner, respectively. Again, for both aligner thicknesses, the tooth’s center of rotation moved lingually and towards the root direction in lingual inclination, and diagonally from the long axis of the tooth in axial rotation. Taken together, orthodontic treatment for simple malocclusions using transparent aligners of different thicknesses will produce a similar effect on the principal stresses in the periodontal ligament and similar changes in the tooth’s center of rotation, as well as sufficient tooth movement. These findings provide orthodontists and researchers clinical and biomechanical evidence about the effect of transparent aligner thickness selection and its effect on orthodontic treatment.