Optimization of polydimethylsiloxane (PDMS) surface chemical modification and formulation for improved T cell activation and expansion.

Adoptive T cell therapy has undergone remarkable advancements in recent decades; nevertheless, the rapid and effective ex vivo expansion of tumor-reactive T cells remains a formidable challenge, limiting their clinical application. Artificial antigen-presenting substrates represent a promising avenue for enhancing the efficiency of adoptive immunotherapy and fostering T cell expansion. These substrates offer significant potential by providing flexibility and modularity in the design of tailored stimulatory environments. Polydimethylsiloxane (PDMS) silicone elastomer stands as a widely utilized biomaterial for exploring the varying sensitivity of T cell activation to substrate properties. This paper explores the optimization of PDMS surface modification and formulation to create customized stimulatory surfaces with the goal of enhancing T cell expansion. By employing soft PDMS elastomer functionalized through silanization and activating agent, coupled with site-directed protein immobilization techniques, a novel T cell stimulatory platform is introduced, facilitating T cell activation and proliferation. Notably, our findings underscore that softer modified elastomers (Young' modulus E∼300 kPa) exhibit superior efficacy in stimulating and activating mouse CD4+ T cells compared to their stiffer counterparts (E∼3 MPa). Furthermore, softened modified PDMS substrates demonstrate enhanced capabilities in T cell expansion and Th1 differentiation, offering promising insights for the advancement of T cell-based immunotherapy.

miR-197-3p Promotes Osteosarcoma Stemness and Chemoresistance by Inhibiting SPOPL.

First-line treatment for osteosarcoma includes chemotherapy and surgery. However, the five-year survival rate of refractory osteosarcoma remains unsatisfactory. Osteosarcoma cancer stem cells, possessing stemness and chemoresistance, are one of the critical causes of poor response to chemotherapy. Elucidating regulatory signaling pathways of osteosarcoma cancer stem cells may provide a rationale for improving regimens against chemoresistant osteosarcoma. Methotrexate (MTX)-resistant osteosarcoma cells were established. microRNA expression profiles were used for detecting differentially expressed microRNA in resistant clones and the parental cells. microRNA target databases were employed to predict potential microRNA and mRNA interactions. Flow cytometry was performed to measure stem cell marker Prominin-1 (CD133)-positive cells. Immunofluorescence staining was applied to detect CD133 expression. miR-197-3p mimic or anti-miR-197-3p stably transfected cells were used to generate xenograft models. In the study, we found that miR-197-3p was increased in MTX-resistant cell lines. Overexpression of miR-197-3p enhanced the expression of cancer stem cell markers CD133, Octamer-binding protein 4 (OCT4), Transcription factor SOX-2 (SOX2), and Homeobox protein NANOG (NANOG), as well as chemoresistance-associated genes ATP-dependent translocase ABCB1 (ABCB1) and Broad substrate specificity ATP-binding cassette transporter ABCG2 (ABCG2), whereas miR-197-3p knockdown inhibited stemness and recovered sensitivity to MTX. We also classified the tumor suppressor Speckle-type POZ protein-like (SPOPL) as a target of miR-197-3p. The miR-197-3p mutation that could not combine SPOPL promoter regions was unable to sustain stemness or chemoresistance. Collectively, we discovered miR-197-3p conferred osteosarcoma stemness and chemotherapy resistance by targeting SPOPL, prompting promising therapeutic candidates for refractory osteosarcoma treatment.

Mending a broken heart-targeting cardiomyocyte regeneration: a literature review.

Background and Objectives: Cardiovascular diseases have been the leading cause of death globally for decades. Pharmacological advances targeting the sympathetic nervous system, renin-angiotensin-aldosterone system, and fibrosis slow the progression of diverse cardiovascular diseases. However, ongoing cardiomyocyte loss is inevitable in divergent cardiovascular diseases, eventually leading to heart failure as the end stage. In this review, we focused on the key biomedical findings and underlying principles of cardiomyocyte regeneration. Methods: Literature regarding the key findings in cardiomyocyte regeneration research, including controversies on the origins of newly formed cardiomyocytes, potential barriers and strategies to heart regeneration, and the key animals, models, and methods applied in the study of heart regeneration, were broadly researched using the PubMed and Web of Science databases. Key Content and Findings: In the mammalian heart, cardiomyocytes proliferate during the embryonic and early postnatal stages, while the capability of proliferation disappears in the adult stage. An increasing amount of evidence suggests that cardiomyocytes self-renew at a very limited level and that most newly formed cardiomyocytes originate from pre-existing cardiomyocytes and not cardiac progenitor cells (CPCs). Several potential barriers to heart regeneration have been addressed, including metabolic switch, a large increase in multinucleated and polyploid cardiomyocytes, and alteration in the epigenome and transcriptome. In addition, immune system evolution is also associated with the loss of regenerative capacity. However, the activation of resident cardiomyocytes, somatic cell reprogramming, and direct reprogramming, in addition to the promotion of neovascularization and immune modulation, constitute the new insights into those strategies that can boost cardiac regeneration. Conclusions: Heart regeneration is one of the most popular fields in cardiovascular research and represents a promising avenue of therapeutics for mending a broken heart. Despite the controversies and challenges, a clearer picture of adult mammalian cardiac regeneration is emerging.

Dexras1 Induces Dysdifferentiation of Oligodendrocytes and Myelin Injury by Inhibiting the cAMP-CREB Pathway after Subarachnoid Hemorrhage.

White matter damage (WMD), one of the research hotspots of subarachnoid hemorrhage (SAH), mainly manifests itself as myelin injury and oligodendrocyte differentiation disorder after SAH, although the specific mechanism remains unclear. Dexamethasone-induced Ras-related protein 1(Dexras1) has been reported to be involved in nervous system damage in autoimmune encephalitis and multiple sclerosis. However, whether Dexras1 participates in dysdifferentiation of oligodendrocytes and myelin injury after SAH has yet to be examined, which is the reason for creating the research content of this article. Here, intracerebroventricular lentiviral administration was used to modulate Dexras1 levels in order to determine its functional influence on neurological injury after SAH. Immunofluorescence, transmission electron microscopy, and Western blotting methods, were used to investigate the effects of Dexras1 on demyelination, glial cell activation, and differentiation of oligodendrocyte progenitor cells (OPCs) after SAH. Primary rat brain neurons were treated with oxyhemoglobin to verify the association between Dexras1 and cAMP-CREB. The results showed that Dexras1 levels were significantly increased upon in vivo SAH model, accompanied by OPC differentiation disturbances and myelin injury. Dexras1 overexpression significantly worsened OPC dysdifferentiation and myelin injury after SAH. In contrast, Dexras1 knockdown ameliorated myelin injury, OPC dysdifferentiation, and glial cell activation. Further research of the underlying mechanism discovered that the cAMP-CREB pathway was inhibited after Dexras1 overexpression in the in vitro model of SAH. This study is the first to confirm that Dexras1 induced oligodendrocyte dysdifferentiation and myelin injury after SAH by inhibiting the cAMP-CREB pathway. This present research may reveal novel therapeutic targets for the amelioration of brain injury and neurological dysfunction after SAH.

Characterizing Risk of In-Hospital Mortality Following Subarachnoid Hemorrhage Using Machine Learning: A Retrospective Study.

Background: Subarachnoid hemorrhage has a high rate of disability and mortality, and the ability to use existing disease severity scores to estimate the risk of adverse outcomes is limited. Collect relevant information of patients during hospitalization to develop more accurate risk prediction models, using logistic regression (LR) and machine learning (ML) technologies, combined with biochemical information. Methods: Patient-level data were extracted from MIMIC-IV data. The primary outcome was in-hospital mortality. The models were trained and tested on a data set (ratio 70:30) including age and key past medical history. The recursive feature elimination (RFE) algorithm was used to screen the characteristic variables; then, the ML algorithm was used to analyze and establish the prediction model, and the validation set was used to further verify the effectiveness of the model. Result: Of the 1,787 patients included in the mimic database, a total of 379 died during hospitalization. Recursive feature abstraction (RFE) selected 20 variables. After simplification, we determined 10 features, including the Glasgow coma score (GCS), glucose, sodium, chloride, SPO2, bicarbonate, temperature, white blood cell (WBC), heparin use, and sepsis-related organ failure assessment (SOFA) score. The validation set and Delong test showed that the simplified RF model has a high AUC of 0.949, which is not significantly different from the best model. Furthermore, in the DCA curve, the simplified GBM model has relatively higher net benefits. In the subgroup analysis of non-traumatic subarachnoid hemorrhage, the simplified GBM model has a high AUC of 0.955 and relatively higher net benefits. Conclusions: ML approaches significantly enhance predictive discrimination for mortality following subarachnoid hemorrhage compared to existing illness severity scores and LR. The discriminative ability of these ML models requires validation in external cohorts to establish generalizability.

Photocurable Hydrogel Substrate-Better Potential Substitute on Bone-Marrow-Derived Dendritic Cells Culturing.

Dendritic cells (DCs) are recognized as the most effective antigen-presenting cells at present. DCs have corresponding therapeutic effects in tumor immunity, transplantation immunity, infection inflammation and cardiovascular diseases, and the activation of T cells is dependent on DCs. However, normal bone-marrow-derived Dendritic cells (BMDCs) cultured on conventional culture plates are easy to be activated during culturing, and it is difficult to imitate the internal immune function. Here, we reported a novel BMDCs culturing with hydrogel substrate (CCHS), where we synthesized low substituted Gelatin Methacrylate-30 (GelMA-30) hydrogels and used them as a substitute for conventional culture plates in the culture and induction of BMDCs in vitro. The results showed that 5% GelMA-30 substrate was the best culture condition for BMDCs culturing. The low level of costimulatory molecules and the level of development-related transcription factors of BMDCs by CCHS were closer to that of spleen DCs and were capable of better promoting T cell activation and exerting an immune effect. CCHS was helpful to study the transformation of DCs from initial state to activated state, which contributes to the development of DC-T cell immunotherapy.