Adipose-derived stem cell-based optimization strategies for musculoskeletal regeneration: recent advances and perspectives.

Musculoskeletal disorders are the leading causes of physical disabilities worldwide. The poor self-repair capacity of musculoskeletal tissues and the absence of effective therapies have driven the development of novel bioengineering-based therapeutic approaches. Adipose-derived stem cell (ADSC)-based therapies are being explored as new regenerative strategies for the repair and regeneration of bone, cartilage, and tendon owing to the accessibility, multipotency, and active paracrine activity of ADSCs. In this review, recent advances in ADSCs and their optimization strategies, including ADSC-derived exosomes (ADSC-Exos), biomaterials, and genetic modifications, are summarized. Furthermore, the preclinical and clinical applications of ADSCs and ADSC-Exos, either alone or in combination with growth factors or biomaterials or in genetically modified forms, for bone, cartilage, and tendon regeneration are reviewed. ADSC-based optimization strategies hold promise for the management of multiple types of musculoskeletal injuries. The timely summary and highlights provided here could offer guidance for further investigations to accelerate the development and clinical application of ADSC-based therapies in musculoskeletal regeneration.

Shape-Morphing Liquid-Crystal polymers.

Liquid-crystal polymers are a type of representative material combining the order-disorder transition of liquid crystals and the superior properties of polymers. The phase transition from the liquid-crystal phase to the isotropic state of mesogens causes large, controllable, and reversible deformation of polymers; thus, liquid-crystal polymers have emerged as one of the most valuable candidates for shape-morphing materials. Therefore, this review will focus on the recent development of shape-morphing liquid-crystal polymers, including the modes of energy conversions, material design strategies and further applications. In the main, novel material design methods and a wide range of application of shape-morphing liquid-crystal polymers are discussed.

Decreased numbers and sex-based differences of circulating regulatory T cells in patients with seropositive undifferentiated arthritis.

AIMS: CD4+ T cells play crucial roles as both mediators and regulators of the pathogenesis of rheumatoid arthritis (RA). However, the characteristics of CD4+ T cell subpopulations in the earliest stage of RA development remain unclear. Hence, we determined the proportions and absolute counts of circulating CD4+ T cell subsets in patients with seropositive undifferentiated arthritis (SUA), the early and preclinical stage of RA. METHODS: Peripheral blood samples and clinical information were collected from 177 patients with SUA, 104 patients with RA, and 120 healthy controls. All patients were newly diagnosed and untreated. Proportions and absolute counts of CD4+ T cell subpopulations were determined by flow cytometric analysis. RESULTS: In patients with SUA, percentages and absolute counts of circulating regulatory T (Treg) cells were decreased significantly and Th17/Treg cell ratios were abnormally increased, whereas Th17 cell numbers were similar to those in healthy controls. In addition, sex-based differences in circulating Treg cells were observed, with female SUA patients having lower proportions and absolute counts of Treg cells than those in males. Moreover, female patients with SUA had higher erythrocyte sedimentation rates and 28-joint Disease Activity Scores than those in males. CONCLUSION: Immune tolerance deficiency resulting from an abnormal reduction in circulating Treg cells might be the most crucial immunological event in the earliest stage of RA. The sex-specific disparity in Treg cells should also be considered for immunoregulatory and preventive strategies targeting early RA.