Project description:After establishing a subcutaneous 4T1 tumor model in mice, we conducted PATCH treatment using HA-PCN. Tumors were harvested post-treatment for single-cell RNA sequencing to analyze cellular and transcriptional changes within the tumor microenvironment.
Project description:Therapeutic and diagnostic illumination on internal organs and tissues with high controllability and adaptability in terms of spectrum, area, depth, and intensity remains a major challenge. Here, we present a flexible, biodegradable photonic device iCarP featured with a micrometer scale air gap constructed between a refractive polyester patch and the embedded removable tapered optical fiber (TOF). ICarP combines the advantages of light diffraction by TOF, dual refractions on TOF/air and air/patch interfaces of the air gap, and reflection inside the patch to obtain a “bulb-like” illumination, guiding the light towards the target tissue. Large area, high intensity, wide spectrum, continuous/pulsatile, deeply penetrating illumination was achieved without puncturing the target tissues. ICarP supported phototherapies with different photosensitizers and achieved higher efficacy compared to optical fibers with clinically relevant optical fiber structures, attributed to the light scattering effect. The robust photonic device is compatible with thoracoscopy-based minimally invasive implantation and exhibited consistent performance on mechanically dynamic animal hearts in a demonstrative application of in situ photosynthesis for myocardial infarction treatment. The iCarP phototherapy improved survival of cardiac cells and preserved cardiac functions. These initial results showed that iCarP could be a safe, precise and widely applicable device suitable for internal organs/tissues illumination and associated therapy and diagnosis.
Project description:We employed MNase-seq and ChIP-seq to determine irregularities in chromatin architecture in mutants of the nucleosome acidic patch. Indeed, the acidic patch mutant showed defects in nucleosome positioning and occupancy at genes with high expression and H2B K123ub levels, linking the acidic patch to transcription-dependent chromatin changes. Our results emphasize the importance of the nucleosome core as a hub for proteins that regulate chromatin during transcription.
Project description:The H2A variant H2AZ is essential for embryonic development and for proper execution of developmental gene expression programs in embryonic stem cells (ESCs). Divergent regions in H2AZ are likely key for its functional specialization, but we know little about how these differences contribute to chromatin regulation. Here, we show that the extended acidic patch, specifically the three divergent residues in the C-terminal docking domain, is necessary for lineage commitment during ESC differentiation and proper execution of gene expression programs during ESC differentiation. Surprisingly, disruption of the acidic patch domain has a distinct consequence on cellular specification compared to H2AZ depletion. This is consistent with differences in gene expression profiles of H2AZ M-bM-^@M-^Sdepleted and acidic patch (AP) mutant ESCs during early lineage commitment. Interestingly, the distinct consequence of AP mutant expression on gene regulation is coincidence with an altered destabilized chromatin state and high chromatin mobility dependent on active transcription. Collectively, our data shows that the divergent residues within the acidic patch domain are key structural determinants of H2AZ function and links chromatin structure and dynamics with gene regulation and cell fate specification. H2AZ extended acidic patch was mutated, or H2AZ was KD in mouse embryonic stem cells and RNA-Seq analysis was performed on the resulting cultures. Characterization of H2AZ-WT and -AP3-mutant binding specificities were performed by ChIP-Seq.
Project description:Myocardial infarction (MI) is a leading cause of death globally. Stem cell therapy is considered a potential strategy for MI treatment. Transplantation of classic stem cells including embryonic, induced pluripotent and cardiac stem cells exhibited certain repairing effect on MI via supplementing cardiomyocytes, however, their clinical applications were blocked by problems of cell survival, differentiation, functional activity and also biosafety and ethical concerns. Here, we introduced human amniotic epithelial stem cells (hAESCs) featured with immunomodulatory activities, immune-privilege and biosafety, for constructing a stem cell cardiac patch based on porous antioxidant polyurethane (PUR), which demonstrated decent hAESCs compatibility. In rats, the administration of PUR-hAESC patch significantly reduced fibrosis and facilitated vascularization in myocardium after MI and consequently improved cardiac remodeling and function. Mechanistically, the patch facilitated a desirable immune response for cardiac repair, framing the infiltration of neutrophils and inflammatory macrophages. Our findings may provide a potential therapeutic strategy for MI.
Project description:Treatment-resistance of lethal high-grade brain tumors including H3K27M diffuse midline gliomas is thought to arise in part from transcriptional and electrophysiological heterogeneity. These phenotypes are readily studied in isolation using single-cell RNA-seq and whole-cell patch clamping, respectively, but their simultaneous capture is now possible by aspirating a cell's contents into a patch pipet after electrophysiology recordings using a method called 'patch-seq'. Here, we adapt this method to characterize the gene expression programs and functional responses of patient-derived glioma xenografts to neuronal firing at single-cell resolution.
Project description:Corneal alkali burns cause persistent inflammation, leading to corneal vascularization and fibrosis, which severely impair vision. Here, we developed a temporary adhesive silk-based patch to capture and remove inflammatory mediators from the ocular surface. The patch utilizes photocrosslinkable silk for mechanical support, chitosan as the adhesive, hyaluronan for lubrication, and polyamidoamine (PAMAM) dendrimers with heparin to enhance adsorption. After water annealing, the patch exhibited excellent transparency, mechanical strength, and resistance to swelling, remaining attached to the rat ocular surface for 3–5 days. Adsorption tests confirmed that the patch effectively captured small-molecule dyes, proteins, and free DNA. In the rat corneal alkali burn model, imaging and histological evaluations showed significant reductions in vascularization and fibrosis after 3 days of treatment, along with improved corneal transparency. RNA sequencing revealed that patch treatment effectively inhibited the PI3K–AKT inflammatory pathway. This inflammation-removing patch represents an innovative treatment for corneal alkali burns with significant clinical potential.
Project description:Microneedle patches are widely employed in pain-free drug delivery, biosensing, and cosmetic applications. However, weak tissue adhesion remains a major challenge in clinical translation of microneedle patches. Here, mimicking the structural features of honeybee stingers, stiff polymeric microneedles with unidirectionally backward facing barbs were fabricated and embedded into various elastomer films to produce self-interlocking microneedle patches. The spirality of the barbing pattern was adjusted to increase interlocking efficiency. In the challenging working condition of animal hearts beat with large cyclic strains, the barbs provided 0.4 N interlocking force, which resulted in firm fixation of the bioinspired microneedle patch. In addition, the minimal bleeding caused by microneedle puncturing adhered the porous surface of the patch substrate between microneedles to the epicardium via coagulation. In the demonstrative application of myocardial infarction treatment, the microneedle patches significantly reduced cardiac wall stress and strain in the infarct and border zone, maintaining left ventricular function and morphology. In addition, the microneedle patch was minimally invasively implanted onto beating porcine heart free of sutures and adhesives, and the fixation step only took 2 minutes. Therefore, the honeybee stinger inspired microneedles could provide an adaptive and convenient means to adhere patches for various medical applications.