Biology subjects

Xu, K.

Publications and source records attributed to Xu, K..

At least 55 records · Page 3Linked to original sources

bioRxiv2025

TaoChongBao: A Large-Scale Caenorhabditis elegans Mutagenesis and Missense Variant Database Bridging Worm and Human Genomes

We generated and sequenced 12,069 viable Caenorhabditis elegans strains produced by ethyl methanesulfonate mutagenesis, identifying 20,315,536 variants, including 541,102 unique missense mutations across 20,914 genes. To organize and visualize this resource, we developed TaoChongBao, an open-access database and strain repository that integrates C. elegans mutation data with AlphaMissense-predicted pathogenicity scores and ClinVar clinical annotations. TaoChongBao enables users to explore worm missense variants, identify conserved residues corresponding to human pathogenic sites, and access viable strains for experimental validation. Compared with the previous Million Mutation Project in C. elegans, TaoChongBao expands mutation coverage over twenty-fold and emphasizes amino acid-altering variants. This resource provides a scalable platform for functional residuomics, variant interpretation, and comparative analyses between C. elegans and human genomes.

bioinformatics↗

bioRxiv2025

Noninvasive enrichment of circulating tumor biomarkers in a mouse model of diffuse midline glioma using focused ultrasound

BackgroundDiagnosing diffuse midline glioma (DMG) through invasive tissue biopsies is challenging due to the tumors eloquent location at the pons. Liquid biopsies offer a promising noninvasive alternative; however, their limited detection sensitivity and lack of information on the source of biomarkers pose great challenges. This study aimed to evaluate the feasibility and safety of using focused ultrasound (FUS) with microbubbles to enrich circulating DMG tumor biomarkers in blood and cerebrospinal fluid (CSF) using a mouse model. MethodsMurine DMG cells, transfected with enhanced green fluorescent protein (EGFP) and firefly luciferase (Fluc) genes, were orthotopically injected into the mouse brain. Magnetic resonance imaging was used to guide FUS targeting of the DMG tumor. Droplet digital PCR assays were developed to detect circulating tumor DNA (ctDNA) and RNA (ctRNA) of EGFP and Fluc in blood and CSF samples collected after FUS. ResultsFUS enhanced the plasma levels of EGFP ctRNA by 5.4-fold (p=0.0112), compared with liquid biopsy without FUS. CSF EGFP ctDNA was increased by 2.5-fold (p=0.0253), and Fluc ctDNA was increased by 2.6-fold (p=0.0253) with FUS. No brain tissue damage was associated with FUS sonication. ConclusionsThis study demonstrated the feasibility and safety of FUS in enriching tumor biomarkers in blood and CSF in a mouse model of DMG. The enrichment ratio for circulating biomarkers depends on the source (plasma vs. CSF), analyte type (ctDNA vs. ctRNA), and individual marker (EGFP vs. Fluc). These findings support the potential future application of FUS to advance the diagnosis of DMG through liquid biopsy. Key pointsO_LIddPCR assays were developed to detect plasma and CSF ctDNA and ctRNA in a mouse model of DMG C_LIO_LIFUS with microbubbles enriched ctDNA and ctRNA in the blood and CSF of a mouse model of DMG C_LIO_LIThe enrichment ratio on circulating biomarkers is dependent on the source (plasma vs. CSF), analyte type (ctDNA vs. ctRNA), and individual marker (EGFP vs. Fluc) C_LI Importance of the studyLiquid biopsy via detecting circulating tumor biomarkers holds enormous clinical value in the diagnosis of diffuse midline glioma (DMG), where the eloquent location of the tumor poses significant risks to invasive surgical tissue biopsies. However, the effectiveness of liquid biopsy is hindered by its low sensitivity and the lack of information about the source of biomarkers. This study demonstrated that noninvasive and spatially targeted FUS treatment can release tumor-derived DNA and RNA into the blood and CSF in a mouse model of DMG. This study also found that the enrichment effect of FUS on circulating biomarkers depends on the source (plasma vs. CSF), analyte type (ctDNA vs. ctRNA), and individual marker (EGFP vs. Fluc). This study opens new avenues for advancing noninvasive DMG diagnosis through FUS-enhanced liquid biopsy (sonobiopsy).

bioengineering↗

bioRxiv2025

Full-length structure of CPR-containing self-sufficient cytochrome P450

Cytochrome P450 (P450s) are heme-thiolate monooxygenases that exploit electrons sourced from pyridine nucleotide to reduce the oxygen and heme iron to catalyze hydroxylation of inactivated C-H bond1-4. Self-sufficient P450s that contain the substrate-binding heme-domain and the electron-donating NADPH:cytochrome P450 reductase (CPR) domain in the same polypeptide chain are highly effective and have been engineered to catalyze various challenging reactions. The high efficacy attributes to the effective electron transfer rate, but how the electrons travel among the redox centers remains elusive owing to the lack of structural information of the full-length protein. Here, we report the structure of a homologue of the most extensively studied P450BM3 from Shimazuella soli (SoP450) resolved by single particle cryo-electron microscopy (cryo-EM) and X-ray crystallography. SoP450 primarily exists as a homodimer formed via the intertwined CPR-domains. The spatial alignment of the heme-domain that is linked via an extensive loop was also determined. Notably, a class of structure that lacks one heme-domain was identified from the cryo-EM analyses, indicating that the heme-domain is mobile. We suspected that the heme-domain could move to reach the CPR-domain for electron acquisition and built a model of putative catalytic state to reveal how the electrons are relayed from NADPH to heme. These results are of fundamental importance to understand the catalytic reaction of CPR-containing self-sufficient P450s, which shall provide critical information to the engineering and applications of these enzymes.

synthetic biology↗

bioRxiv2025

Class-I myosin responds to change in membrane tension during clathrin-mediated endocytosis in human induced pluripotent stem cells

Clathrin-mediated endocytosis (CME) is an essential cellular process that needs to operate efficiently across a wide range of conditions. Internalization of the endocytic site involves forces generated by membrane-bound proteins and Arp2/3-mediated branched actin filament assembly to bend the plasma membrane (PM) from flat to omega-shaped. In mammalian CME, the requirement for a branched actin filament network varies depending on cell type and differences in membrane tension. However, how the actin network adapts to changes in load in order to ensure robustness of this process over a range of membrane tensions is not understood. Here, we combine live-cell imaging and super-resolution microscopy of genome-edited human induced pluripotent stem cells (hiPSCs) to investigate the role of the mammalian class-I myosin, Myosin1E (Myo1E), in load adaptation. Under normal conditions, sites that recruit Myo1E are rare and exhibit slow CME dynamics. However, as membrane tension increases and CME dynamics are slowed globally, Myo1E is recruited to more sites, likely to assemble more branched actin, resulting in increased force generation to rescue stalled sites and promote internalization. Loss of Myo1E results in increased Arp2/3 complex lifetime at CME sites under normal conditions, and at high membrane tension, these sites fail to recruit as many Arp2/3 molecules. We propose that Myo1E is recruited to CME sites that have stalled due to increased membrane tension, where it helps build a more effective branched actin network by generating force through motor activity and recruiting additional Arp2/3 complexes to rescue stalled sites. SignificanceFor mammalian cells to internalize extracellular cargo via clathrin-mediated endocytosis (CME), specific regions of the plasma membrane (PM) must bend from flat to inwardly curved, a process that requires force-generating proteins. One key component in generating this force during CME is the branched actin network, in which actin filaments polymerize against the plasma membrane. When PM tension increases, more force is required to generate curvature, prompting the assembly of actin and actin associated proteins to aid the process. We demonstrate that the class-I myosin motor, Myosin1E (Myo1E), becomes increasingly crucial as membrane tension rises, presumably to build a more effective branched actin network to facilitate internalization of slowed sites.

cell biology↗

bioRxiv2025

ProAffinity++

Proteins are essential biological macromolecules that play a crucial role in living organisms. Protein-protein interactions, which govern various biological processes such as signal transduction, cell metabolism, and cell growth, are key aspect of protein function. The strength of these interactions, characterized by protein-protein binding affinity({Delta}G), is a critical thermodynamic property of protein complexes. Accurate prediction of protein-protein binding affinity is meaningful for understanding the mechanisms of biological systems and improving the speed of binding affinity determination. However, current methods are limited in their accuracy and are primarily designed for binary complexes. To address these limitations, we propose ProAffinity++, an end-to-end algorithm that predicts binding affinities using a combined representation of sequence and structure. The core idea of ProAffinity++ is to model the binding regions of protein complexes and utilize graph neural networks to capture the local microenvironment of residues. Our experimental evaluations demonstrate that ProAffinity++ outperforms state-of-the-art methods in predicting protein-protein binding affinities. Moreover, it exhibits remarkable performance in challenging scenarios, such as antigen-antibody interactions and missense mutation problems, where existing methods have limitations.

bioinformatics↗

bioRxiv2025

An ultra-long acting insulin enables glucose-synchronised release

Delayed and weak glucose-responsive kinetics, coupled with short plasma exposure and complicated formulation, remain major obstacles to the clinical translation of glucose-responsive insulin formulations. Here we report a rapidly absorbable, ultra-long acting, and glucose-responsive insulin analogue via engineering recombinant human insulin with two phenylboronic acids. The insulin analogue has a long circulating half-life (t1/2{beta} [~]150 h) due to its unique, unprecedented, glucose-responsive binding to blood circulation-associated proteins. This interaction drives the formation of a unique systemic reservoir that allows synchronised dynamic response in insulin levels to glucose fluctuations. In type 1 diabetic mice and minipigs, a single subcutaneous dose can maintain normoglycaemia for over one week (47.5-fold compared to insulin glargine). After the last injection of four consecutive weekly administrations in mice, the glucose-lowering effect can last 800 hours. Administering this glucose-responsive insulin analogue with a fully automated insulin delivery system can leverage dual closed loops and achieve a glucose time in range of over 85% and a coefficient of variation of approximately 30%, better than the recommended targets for human therapy. Importantly, no toxicity was identified in the study.

bioengineering↗

bioRxiv2025

CryoSeek identification of glycofibrils with diverse compositions and structural assemblies

Last year, we reported CryoSeek, a research strategy that employs cryo-electron microscopy (cryo-EM) to discover novel bio-entities from any accessible source, supplemented with AI-facilitated data processing and bioinformatic analyses. Here we report CryoSeek characterization of five additional glycofibrils isolated from the Tsinghua Lotus Pond (TLP), named TLP-IPT, TLP-12, TLP-3, TLP-2, and TLP-0, with overall resolutions ranging from 3.0-3.5 [A]. These five glycofibrils, all covered with dense glycoshells, have decreasing ratios of the central protein components, with TLP-0 with no protein at all. IPT (immunoglobulin-like, plexins, transcription factors) refers to the tandem domain that constitutes the central filament of this type of glycofibrils. In TLP-12, the central cylindrical stem is made of a trimer of dodecapeptide repeats that weave to {beta}-sheet ribbons. The central stem of TLP-3 is also a trimer, but of linear tripeptide repeats. TLP-2, similar to our previously reported TLP-4, only has a linear chain of dipeptide repeats, and glycosylation occurs to a phosphoserine in each repeat. Glycan-mediated interactions are essential for the assembly of all five glycofibrils. Our previous and present studies demonstrate the diversity in the high-order structure and folding of glycans.

biophysics↗

bioRxiv2025

Mutations in the ubiA gene are the major mechanism of ethambutol resistance in Mycobacterium avium

Mycobacterium avium-intracellulare complex (MAC) infections are the most common nontuberculous mycobacterial (NTM) infections, and ethambutol (EMB) is one of the main therapeutic agents used to treat MAC infections. However, the EMB resistance profile and its resistance mechanisms in M. avium remain poorly understood. This study determined the minimum inhibitory concentration (MIC) on 40 M. avium clinical strains, revealing that 97.5% (39/40) of the strains were intermediate (MIC=4 g/mL) or resistant (MIC[≥]8 g/mL) to EMB. One susceptible clinical isolate strain 245 (MIC=2 g/mL) was picked for EMB-resistant mutant isolation, and a total of 121 resistant mutants were isolated and subjected to whole-genome sequencing or Sanger sequencing. Integrated analysis revealed that 94.21% (114/121) of the mutants carried mutations in the ubiA gene, which encodes DPPR (decaprenylphosphoryl-{beta}-D-5-phosphoribose) synthase - an enzyme involved in cell wall biosynthesis that has been associated with high-level EMB resistance in M. tuberculosis. Complementation with the wild-type ubiA gene restored EMB susceptibility in EMB-resistant mutants and clinical strain 322 (EMB MIC=64 g/mL) with ubiA mutation, reducing the MICs from 32 g/mL to 4 g/mL and from 64 g/mL to 8 g/mL, respectively. This study indicates that the ubiA mutation is the major mechanism of EMB resistance in M. avium, which should facilitate the development of molecular tests for rapid detection of resistance in this organism.

microbiology↗

bioRxiv2025

Mosquito vector ecologies are destabilizing as a result of climate change

Mosquito-borne infectious disease is a major cause of mortality and a significant economic burden worldwide. Shifting regional and seasonal patterns make proactive intervention challenging. Here we introduce a machine learning approach trained on satellite and mosquito observational data, improving generalizability to sparse observations while retaining similar positive performance characteristics of models used in standard practice. We provide global estimates for Aedes habitability at high spatial resolution in five-year increments from 1970-2024. The vast majority of ecologies appear to be destabilizing. Overall, we demonstrate a decrease in risk near the equator and an increase in risk in historically temperate climates including the United States, the European Union, and China. Despite this decrease in risk relative to historical averages, regions near the equator remain among the highest risk worldwide. Together, these results reflect an overall, marked expanse of the regions of the globe that support Aedes mosquitos and we observe an ongoing, linear increase in the global population at risk of contracting mosquito-borne disease.

ecology↗

bioRxiv2025

Unexpected diversity of Isidoides (Anthozoa: Octocorallia: Isidoidae) revealed by morphology and phylogenomics analysis with descriptions of four new species

Isidoidae Heestand Saucier, France & Watling, 2021 is a rare octocoral family currently represented by a single genus and species, Isidoides armata Nutting, 1910 recorded in the western Pacific Ocean. The taxonomic status and diversity of Isidoides is unclear, due to the lack of diagnostic taxonomic features and limited taxon sampling. Based on 23 Isidoides specimens obtained from the northwestern to southwestern Pacific, we carried out morphological and phylogenetic analyses to reveal the taxonomic status of new species and develop reliable features for species identification. The 23 specimens could be classified into four well-supported clades by the phylogenomic analysis of ultraconserved elements (UCEs), four groups by 28S rDNA, and two groups by mtMutS-cox1. Integrating morphology and molecular data, we uncovered unexpected diversity of Isidoides composed of the known species Isidoides armata and three new species, viz., I. elegans sp. nov., I. gracilis sp. nov. and I. pseudarmata sp. nov. The morphological analysis showed high intraspecific morphological variation in colony color and the size, shape and arrangement of polyps. By contrast, sclerite forms with their surface sculpturing are more diagnostic features for species identification. Our phylogenetic and species delimitation analyses indicate that UCEs have higher resolution than the nuclear 28S rDNA and the mitochondrial genes mtMutS and cox1 for species discrimination within Isidoidae. ZooBank: urn:lsid:zoobank.org:pub:392485F5-502E-4383-B153-45B167571190

zoology↗

bioRxiv2025

Small molecule intervention of actin-binding protein profilin1 reduces tumor angiogenesis in renal cell carcinoma

Angiogenesis plays a key role in the development and progression of renal cell carcinoma (RCC). Actin-binding protein profilin-1 (Pfn1) is overexpressed in clear cell RCC predominantly in tumor-associated vascular endothelial cells (ECs). We previously demonstrated that that EC-selective (over)expression of Pfn1 accelerates RCC progression, and conversely, genetic loss of EC-Pfn1 dramatically inhibits tumor angiogenesis impeding tumor initiation and/or progression in RCC, suggesting that Pfn1 could be an actionable therapeutic target in RCC. In this study, we demonstrate that 4,4-((4-bromophenyl)methylene)bis(3,5-dimethyl-1H-pyrazole), a small molecule that we had previously identified as an inhibitor of Pfn1-actin interaction, directly binds to Pfn1 and attenuates tumor angiogenesis when directly administered into subcutaneous RCC tumors. Next, we undertook a chemical optimization approach to design and synthesize 4,4-((4-(trifluoromethyl)phenyl)methylene)bis(3,5-dimethyl-1H-pyrazole), a structural analog of our originally identified inhibitor, that exhibits improved anti-angiogenic efficacy in vitro and in vivo. Finally, we demonstrate that Pfn1 inhibitor is amenable to lipid microbubble encapsulation and release in the tumor microenvironment (TME) by ultrasound-mediated disruption of circulating microbubbles to achieve anti-angiogenic and anti-tumor benefit. In summary, our findings suggest that tumor-localized release of Pfn1 inhibitor could be a potential therapeutic strategy in RCC.

cell biology↗

bioRxiv2025

Selenoprotein P Deficiency Drives Hepatocellular Carcinoma Progression via Induction of Neutrophil Senescence and Immunosuppressive Microenvironment

The tumor immune microenvironment (TIME) is critically shaped by immunosuppressive neutrophils, yet the molecular mechanisms underlying the functional reprogramming of these neutrophils remain poorly understood. Here, through integrative analysis of single-cell RNA sequencing (scRNA-seq) we showed the presence, in hepatocellular carcinoma (HCC) mice, of a novel subpopulation of senescent-like neutrophils that exhibit hepatic depletion of Sepp1 in concert with the accumulation of the cellular senescence marker Cdkn1a, the immunosuppressive proteins S100a8 and 9, and the pro-angiogenic factor Vegfa. Furthermore, we demonstrated that the hepatic depletion of Sepp1, in combination with this unique subset of senescent neutrophils, drives immunosuppressive activity and further accelerates tumor growth. Mechanistically, the loss of tumor cell-derived Sepp1 impaired selenium uptake in tumor-infiltrating neutrophils (TINs) by disrupting Lrp8 receptor-mediated transport, thereby suppressing intracellular selenium metabolism. This metabolic perturbation led to reduced hydrogen selenide (H2Se) production and accumulation of S-adenosylmethionine (SAM), resulting in increased levels of trimethylation of lysine 4 on histone H3 protein (H3K4me3) modification in neutrophils and collectively establishing a pro-senescence chromatin landscape in tumor-associated neutrophils. Furthermore, we demonstrated that selenium supplementation not only restores Sepp1 expression but also is essential to reshaping anti-tumor immunity in HCC mice, including reversal of the senescent-like phenotype and providing synergistic effects with anti-Programmed cell death 1 (anti-PD-1) therapy. Collectively, our findings identify SEPP1 as a master regulator acting against neutrophil senescence and the potent immunosuppressive effects of senescence in HCC. We discuss the therapeutic potential of strategies to modulate senescent-like neutrophils and underscore the potential utility of selenium supplementation as an adjuvant to enhance immunotherapy efficacy in liver cancer.

cancer biology↗

bioRxiv2025

Population-specific brain charts reveal Chinese-Western differences in neurodevelopmental trajectories

Human brain charts provide unprecedented opportunities for decoding neurodevelopmental milestones and establishing clinical benchmarks for precision brain medicine 1-7. However, current lifespan brain charts are primarily derived from European and North American cohorts, with Asian populations severely underrepresented. Here, we present the first population-specific brain charts for China, developed through the Chinese Lifespan Brain Mapping Consortium (Phase I) using neuroimaging data from 43,037 participants (aged 0-100 years) across 384 sites nationwide. We establish the lifespan normative trajectories for 296 structural brain phenotypes, encompassing global, subcortical, and cortical measures. Cross-population comparisons with Western brain charts (based on data from 56,339 participants aged 0-100 years) reveal distinct neurodevelopmental patterns in the Chinese population, including prolonged cortical and subcortical maturation, accelerated cerebellar growth, and earlier development of sensorimotor regions relative to paralimbic regions. Crucially, these Chinese-specific charts outperform Western-derived models in predicting healthy brain phenotypes and detecting pathological deviations in Chinese clinical cohorts. These findings highlight the urgent need for diverse, population-representative brain charts to advance equitable precision neuroscience and improve clinical validity across populations.

neuroscience↗

bioRxiv2025

RWKV-IF: Efficient and Controllable RNA Inverse Folding via Attention-Free Language Modeling

We present RWKV-IF, an efficient and controllable framework for RNA inverse folding based on the attention-free RWKV language model. By treating structure-to-sequence generation as a conditional language modeling task, RWKV-IF captures long-range dependencies with linear complexity. We introduce a decoding strategy that integrates Top-k sampling, temperature control, and G-C content biasing to generate sequences that are both structurally accurate and biophysically meaningful. To overcome limitations of existing datasets, we construct a large-scale synthetic training set from randomly generated sequences and demonstrate strong generalization to real-world RNA structures. Experimental results show that RWKV-IF significantly outperforms traditional search-based baselines, achieving higher accuracy and full match rate while greatly reducing edit distance. Our approach highlights the potential of lightweight generative models in RNA design under structural and biochemical constraints. The code is available at https://github.com/Lyttr/RWKVInverseFolding.git

bioengineering↗

bioRxiv2025

Ninjurin2 Regulates Vascular Smooth Muscle Cell Phenotypic Switching and Vascular Remodeling through Interacting with PDGF Receptor-β

Vascular smooth muscle cell (VSMC) phenotypic switching from a contractile to synthetic state plays a pivotal role in vascular remodeling. Although genome-wide association studies have linked NINJ2 (encode Ninjurin2) polymorphisms are associated with risk of atherosclerosis and related conditions like ischemic stroke and coronary artery disease, its functional role in regulating VSMC plasticity remains unexplored. Here, using Ninj2 knockout (Ninj2-/-) and smooth muscle-specific overexpressing (Ninj2smcTG) mice subjected to carotid artery ligation, we demonstrate that Ninjurin2 deficiency exacerbates injury-induced intimal hyperplasia, whereas its overexpression attenuates this pathological remodeling. Mechanistically, Ninjurin2 knockdown promoted PDGF-BB-mediated VSMC phenotypic switching, proliferation, and migration, while biochemical studies revealed that Ninjurin2 interacts with PDGFR{beta} to suppress FAK signaling. These findings identify Ninjurin2 as a novel regulator of VSMC phenotypic switching via the PDGFR{beta}/FAK axis, offering new mechanistic insights into vascular remodeling and potential therapeutic avenues for atherosclerosis.

pathology↗

bioRxiv2025

Divergent MIC of Clarithromycin and Azithromycin Against Clinical Isolates of Mycobacterium abscessus Complex

Current treatment guidelines for Mycobacterium abscessus complex (MAB) infections recommend macrolides (clarithromycin/CAM and azithromycin/AZM) as cornerstone therapies, considering them clinically interchangeable without distinction. This study evaluated the comparative in vitro activity of clarithromycin (CAM) and azithromycin (AZM) against 146 clinical isolates of Mycobacterium abscessus complex organisms. MIC distributions revealed significantly higher resistance to AZM (94.5% resistant at [≥]8 g/mL) compared to CAM (77.4% resistant at [≥]8 g/mL), with only 4.8% of isolates susceptible to both drugs. Notably, 26 strains (17.8% of total) showed AZM resistance despite being non-resistant to CAM (MIC <8 g/mL) among 146 clinical isolates. Among the 33 CAM-non-resistant isolates (including susceptible and intermediate strains), 78.8% (26/33) were AZM-resistant, demonstrating frequent discordance in susceptibility profiles. These findings contrast with current treatment guidelines that recommend using CAM and AZM interchangeably without distinction. Subspecies analysis showed three distinct susceptibility profiles: isolates susceptible to both antibiotics (n=3, M. massiliense), isolates resistant to both antibiotics (n=3, M. massiliense), and M. bolletii with CAM-susceptible/AZM-resistant phenotypes (n=2). This differential resistance pattern suggests that while both drugs face substantial resistance challenges, CAM retains meaningful activity against certain strains that are AZM-resistant-particularly in M. bolletii. These findings indicate that AZM and CAM should not be used interchangeably to treat MAB infections and emphasize the need to prioritize CAM over AZM in treatment regimens.

microbiology↗

bioRxiv2025

Divergent Minimum Inhibitory Concentrations of Clarithromycin and Azithromycin Against Clinical Isolates of Mycobacterium abscessus Complex

Current treatment guidelines for Mycobacterium abscessus complex (MAB) infections recommend macrolides (clarithromycin/CAM and azithromycin/AZM) as cornerstone therapies, considering them clinically interchangeable without distinction. This study evaluated the comparative in vitro activity of clarithromycin (CAM) and azithromycin (AZM) against 146 clinical isolates of Mycobacterium abscessus complex organisms. MIC distributions revealed significantly higher resistance to AZM (94.5% resistant at [≥]8 g/mL) compared to CAM (77.4% resistant at [≥]8 g/mL), with only 4.8% of isolates susceptible to both drugs. Notably, 26 strains (17.8% of total) showed AZM resistance despite being non-resistant to CAM (MIC <8 g/mL) among 146 clinical isolates. Among the 33 CAM-non-resistant isolates (including susceptible and intermediate strains), 78.8% (26/33) were AZM-resistant, demonstrating frequent discordance in susceptibility profiles. These findings contrast with current treatment guidelines that recommend using CAM and AZM interchangeably without distinction. Subspecies analysis showed three distinct susceptibility profiles: isolates susceptible to both antibiotics (n=3, M. massiliense), isolates resistant to both antibiotics (n=3, M. massiliense), and M. bolletii with CAM-susceptible/AZM-resistant phenotypes (n=2). This differential resistance pattern suggests that while both drugs face substantial resistance challenges, CAM retains meaningful activity against certain strains that are AZM-resistant--particularly in M. bolletii. These findings indicate that AZM and CAM should not be used interchangeably to treat MAB infections and emphasize the need to prioritize CAM over AZM in treatment regimens.

microbiology↗

bioRxiv2025

Specific Pathogen Free Ten Gene-Edited Pig Donor for Xenotransplantation

Xenotransplantation has entered the clinical phase to fulfill the global organ shortage. However, recent clinical studies revealed that the xenograft from current gene-edited (GE) pigs still poses the risk of immune rejection, and biosafety concerns. In this study, we successfully constructed a large batch of 10- (GTKO/CMAHKO/ {beta}4GalNT2KO/hCD46/hCD55/hCD59/hTBM/hEPCR/hCD39/hCD47) GE cloned (GEC) donor pigs by utilizing gene editing and somatic cell cloning technology, and successfully obtained F1 generation. Phenotypic characterization of 10-GEC pigs showed the deletion of three xenoantigens along with expression of seven human transgenes in various tissues. Digital droplet polymerase chain reaction, and whole genome sequencing indicated 2 copies of hCD46/hCD55/hCD59/hTBM/hCD39 and 1 copy of hEPCR/hCD47 in pig genome without significant off-target and damage to the porcine own functional genes. The validation results showed that 10-GEC pigs effectively inhibited the attacks of human antibodies, complement, and macrophages on porcine endothelial cells and alleviated the coagulation abnormalities between pigs and humans. 10-GEC pigs were negative for all zoonotic pathogens (48) including cytomegalovirus, except streptococcal infections. Kidney, heart, and liver xenografts from these 10-GE pigs were transplanted to non-human primates (NHP), which started working normally without hyperacute rejection. Among them, the heart and liver transplant recipient died without resuscitation due to unexpected interruption of oxygen supply, while the 2 kidney transplant recipients survived for 23 and 16 days, respectively. Pathological analysis showed that 10-GE pig kidney xenografts showed mesenchymal congestion, and fibrosis, cellular hyperplasia, with minor antibody and complement deposition, and significantly reduced the infiltration of CD68+ macrophage. In summary, we successfully produced a group of specific pathogen free GEC donor pigs that effectively mitigated immune rejection upon multi-organ transplantation to NHP.

immunology↗