Microenvironmental reorganization in brain tumors following radiotherapy and recurrence revealed by hyperplexed immunofluorescence imaging.

The tumor microenvironment plays a crucial role in determining response to treatment. This involves a series of interconnected changes in the cellular landscape, spatial organization, and extracellular matrix composition. However, assessing these alterations simultaneously is challenging from a spatial perspective, due to the limitations of current high-dimensional imaging techniques and the extent of intratumoral heterogeneity over large lesion areas. In this study, we introduce a spatial proteomic workflow termed Hyperplexed Immunofluorescence Imaging (HIFI) that overcomes these limitations. HIFI allows for the simultaneous analysis of > 45 markers in fragile tissue sections at high magnification, using a cost-effective high-throughput workflow. We integrate HIFI with machine learning feature detection, graph-based network analysis, and cluster-based neighborhood analysis to analyze the microenvironment response to radiation therapy in a preclinical model of glioblastoma, and compare this response to a mouse model of breast-to-brain metastasis. Here we show that glioblastomas undergo extensive spatial reorganization of immune cell populations and structural architecture in response to treatment, while brain metastases show no comparable reorganization. Our integrated spatial analyses reveal highly divergent responses to radiation therapy between brain tumor models, despite equivalent radiotherapy benefit.

Particle Size-Controlled Oxygen Reduction and Evolution Reaction Nanocatalysts Regulate Ru(bpy)32+'s Dual-potential Electrochemiluminescence for Sandwich Immunoassay.

Multiple signal strategies remarkably improve the accuracy and efficiency of electrochemiluminescence (ECL) immunoassays, but the lack of potential-resolved luminophore pairs and chemical cross talk hinders their development. In this study, we synthesized a series of gold nanoparticles (AuNPs)/reduced graphene oxide (Au/rGO) composites as adjustable oxygen reduction reaction and oxygen evolution reaction catalysts to promote and modulate tris(2,2'-bipyridine) ruthenium(II) (Ru(bpy)32+)'s multisignal luminescence. With the increase in the diameter of AuNPs (3 to 30 nm), their ability to promote Ru(bpy)32+'s anodic ECL was first impaired and then strengthened, and cathodic ECL was first enhanced and then weakened. Au/rGOs with medium-small and medium-large AuNP diameters remarkably increased Ru(bpy)32+'s cathodic and anodic luminescence, respectively. Notably, the stimulation effects of Au/rGOs were superior to those of most existing Ru(bpy)32+ co-reactants. Moreover, we proposed a novel ratiometric immunosensor construction strategy using Ru(bpy)32+'s luminescence promoter rather than luminophores as tags of antibodies to achieve signal resolution. This method avoids signal cross talk between luminophores and their respective co-reactants, which achieved a good linear range of 10-7 to 10-1 ng/ml and a limit of detection of 0.33 fg/ml for detecting carcinoembryonic antigen. This study addresses the previous scarcity of the macromolecular co-reactants of Ru(bpy)32+, broadening its application in biomaterial detection. Furthermore, the systematic clarification of the detailed mechanisms for converting the potential-resolved luminescence of Ru(bpy)32+ could facilitate an in-depth understanding of the ECL process and should inspire new designs of Ru(bpy)32+ luminescence enhancers or applications of Au/rGOs to other luminophores. This work removes some impediments to the development of multisignal ECL biodetection systems and provides vitality into their widespread applications.

Heparanase Modulates Chromatin Accessibility.

Heparanase is the sole endoglucuronidase that degrades heparan sulfate in the cell surface and extracellular matrix (ECM). Several studies have reported the localization of heparanase in the cell nucleus, but the functional role of the nuclear enzyme is still obscure. Subjecting mouse embryonic fibroblasts (MEFs) derived from heparanase knockout (Hpse-KO) mice and applying transposase-accessible chromatin with sequencing (ATAC-seq), we revealed that heparanase is involved in the regulation of chromatin accessibility. Integrating with genome-wide analysis of chromatin states revealed an overall low activity in the enhancer and promoter regions of Hpse-KO MEFs compared with wild-type (WT) MEFs. Western blot analysis of MEFs and tissues derived from Hpse-KO vs. WT mice confirmed reduced expression of H3K27ac (acetylated lysine at N-terminal position 27 of the histone H3 protein). Our results offer a mechanistic explanation for the well-documented attenuation of inflammatory responses and tumor growth in Hpse-KO mice.

The complete chloroplast genome sequence of Polypodiodes amoena (Polypodiaceae), an important medical fern.

Polypodiodes amoena is an important medical fern of Polypodiaceae. Its complete chloroplast genome is obtained through Illumina sequencing, which is 152,067 bp in length with a large single copy (LSC) region (81,187 bp), a small single copy (SSC) region (21,590 bp), and two inverted repeats (IRa and IRb) regions (24,645 bp). The genome encodes 130 genes, including 88 protein-coding genes, 33 tRNA genes, eight rRNA genes, and one pseudogene. ML phylogenetic analysis reveals that P. amoena is clustered with polypodiaceous ferns.