Biology subjects

Zhu, L.

Publications and source records attributed to Zhu, L..

At least 127 records · Page 7Linked to original sources

bioRxiv2024

OfWRKY33 binds to the key linalool synthase gene OfTPS7 to promote linalool synthesis in Osmanthus fragrans flowers

Volatile aroma compounds make significant contributions to human perception of flowers. Osmanthus fragrans is a famous aroma plant and linalool along with its oxides are proved to be the dominant aroma active compounds. Although some terpene synthases (TPSs) have been characterized, a comprehensive study of the hub metabolic gene and its transcriptional regulation remain to be revealed. Here, we selected a specific cultivar Boyeyingui (BBYG) with the highest content of linalool among 20 wide-cultivated cultivars for genome and transcriptome sequencings. Among the 25 new putative OfTPSs, only OfTPS6, OfTPS7 could exclusively produce linalool in planta. Biochemical analysis demonstrated that OfTPS6, OfTPS7 were able to catalyze geranyl diphosphate (GPP) into linalool and a small proportion of other monoterpenes in vitro. Spatial and temporal correlation analysis further confirmed the transcript level of OfTPS7 was closely associated with linalool content in diverse cultivars and different tissues, suggesting OfTPS7 was the essential linalool synthase gene. Combined with yeast one-hybrid screen and weighted correlation network analysis (WGCNA), a nucleus-localized transcriptional factor OfWRKY33 was considered as a potential modulator. Y1H, dual-luciferase assay and electrophoretic mobility shift assay (EMSA) demonstrated that OfWRKY33 directly bound to the W-box of OfTPS7 promoter to stimulate its transcription. OfWRKY33 could coordinately induce the expressions of OfTPS7, 1-deoxy-d-xylulose 1 (OfDXS1), thereby promoting the linalool formation. The results first revealed the hub linalool synthase gene OfTPS7 and a novel TF participating in the complex transcriptional regulation of linalool biosynthesis in O. fragrans flowers.

biochemistry↗

bioRxiv2024

Female-germline specific protein Sakura interacts with Otu and is crucial for germline stem cell renewal and differentiation and oogenesis

During oogenesis, self-renewal and differentiation of germline stem cells (GSCs) must be tightly regulated. The Drosophila female germline serves as an excellent model for studying these regulatory mechanisms. Here, we report that a previously uncharacterized gene CG14545, which we named sakura, is essential for oogenesis and female fertility in Drosophila. Sakura is predominantly expressed in the ovaries, particularly in the germline cells, including GSCs. sakura null mutant female flies display rudimentary ovaries with germline-less and tumorous phenotypes, fail to produce eggs, and are completely sterile. The germline-specific depletion of sakura impairs Dpp/BMP signaling, leading to aberrant bag-of-marbles (bam) expression, resulting in faulty differentiation and loss of GSCs. sakura is also necessary for normal levels of piwi-interacting RNAs (piRNAs) levels and for female-specific splicing of sex-lethal (sxl), a master regulator of sex identity determination. We identified Ovarian Tumor (Otu) as a protein binding partner of Sakura and found that loss of otu phenocopies loss of sakura in ovaries. Thus, we identify Sakura as a crucial factor for GSC renewal and differentiation and oogenesis, and propose that Sakura and Otu function together in these processes.

genetics↗

bioRxiv2024

Tumor Priming by Ultrasound Mechanogenetics for with SynNotch CAR T Therapy

Cell-based cancer immunotherapy holds potential as a therapeutic approach, yet its application for solid tumor treatment remains challenging. We created a system where focused ultrasound (FUS) is able to remotely stimulate gene expressions in a specific tissue area through mechanical induction, gated by a chemical inducer to minimize the background noise. This system, known as CaDox, integrates FUS-triggered mechanical and calcium stimulation with doxycycline-responsive genetic circuits, which allows the localized expression of the clinically validated and specific antigen CD19 within a subpopulation of cancer cells upon FUS stimulation. These CD19-expressing cells can then function as "training centers" that activate synNotch chimeric antigen receptor (CAR) T cells to generate CARs that recognize a less specific but widespread antigen in cancer cells, thereby attacking and suppress the whole cancer cell population nearby at the tumor site. We validated the functionality of this CaDox system in vitro, in organoids, and in vivo, demonstrating its potential for various cell types and as a versatile platform for precisely controllable immunotherapy. Our combinatorial approach thus offers a FUS-controlled remote and non-invasive priming of solid tumors for effective and safe CAR T immunotherapy via the induced production of clinically validated antigens.

synthetic biology↗

bioRxiv2024

Probiotic acoustic biosensors for noninvasive imaging of gut inflammation

Inflammatory bowel diseases (IBD) affect millions of people globally, result in severe symptoms, and are difficult to diagnose and monitor - often necessitating the use of invasive and costly methods such as colonoscopies or endoscopies. Engineered gut bacteria offer a promising alternative due to their ability to persist in the gastrointestinal (GI) tract and sense and respond to specific environmental signals. However, probiotics that have previously been engineered to report on inflammatory and other disease biomarkers in the Gl tract rely on fluorescent or bioluminescent reporters, whose signals cannot be resolved in situ due to the poor penetration of light in tissue. To overcome this limitation, we introduce probiotic biosensors that can be imaged in situ using ultrasound - a widely available, inexpensive imaging modality providing sub-mm spatial resolution deep inside the body. These biosensors are based on the clinically approved probiotic bacterium E. coli Nissle, which we engineered to transiently colonize the GI tract, sense inflammatory biomarkers, and respond by expressing air-filled sound-scattering protein nanostructures called gas vesicles. After optimizing biomolecular signaling circuits to respond sensitively to the biomarkers thiosulfate and tetrathionate and produce strong and stable ultrasound contrast, we validated our living biosensors in vivo by noninvasively imaging antibiotic-induced inflammation in mice. By connecting cell-based diagnostic agents to ultrasound, this "diagnostic yogurt" will make it easier, cheaper, and less painful to diagnose and monitor IBD or other GI conditions.

bioengineering↗

bioRxiv2024

A novel OsIAA3-OsARF16-OsBUL1 module regulates grain size in rice

Auxin plays an important role in almost every aspect of plant growth and development. However, the molecular mechanism underlying the control of grain size via auxin signaling pathways is still obscure. Here, we reported that the rice Aux/IAA gene OsIAA3 positively regulates grain size by promoting the cell expansion and proliferation of spikelet hulls. OsIAA3 interacted with 11 OsARFs, among which the interaction with OsARF16 was the strongest. Knockout of osarf16 led to smaller grain with decreased grain length, grain width, grain thickness and 1,000-grain weight. Meanwhile, transgenic plants overexpressing OsARF16 produced apparently bigger grain with increased grain length and 1,000-grain weight. Additionally, OsBUL1, which positive regulates grain size by promoting cell expansion is a direct target gene of OsARF16. Results demonstrated that the interaction between OsIAA3 and OsARF16 repressed the transcriptional activation of OsARF16 on OsBUL1. Taken together, our study revealed a novel OsIAA3-OsARF16-OsBUL1 module which regulates grain size, enriching the molecular mechanism of auxin signaling pathway involved in regulating grain size.

genetics↗

bioRxiv2024

Early intrinsic plasticity of ACC engram neurons defines memory formation and precision

Neocortical memory engrams are thought to stabilize and mature via enhanced interconnectivity during the so-called systems-consolidation process 1,2. While synaptic plasticity of these engram connections is considered an important mechanism for storing memories 3,4, it cannot fully account for the dynamic vividness of remote, cortically-based memories. Indeed, cell-intrinsic plasticity has been touted as the crucial early priming mechanism that renders nascent engram neurons susceptible to ongoing plastic processes while providing flexibility for later encoding events 5-7. Here, we reveal that learning-related neuron-wide intrinsic excitability (IE) plasticity of nascent cortical engram neurons is a permissive mechanism for the formation and specificity of remote associative memories. Using a c-fos-dependent genetic and viral system for the targeted labeling of engram neurons in the anterior cingulate cortex (ACC) combined with ex vivo electrophysiology, we found that contextual fear learning triggered a time-dependent increase in their IE signature expressed over days during the early, but not late, phase of memory formation. Remarkably, chemogenetically hyperpolarizing engram neurons during this early plastic phase enhanced their maturation, increasing the strength and context-precision of consolidated memories and preventing memory disturbance caused by an interference event. Altogether, our findings identify cell-intrinsic plasticity within nascent ACC engram neurons as an essential tagging mechanism whose features determine the fate and dynamic content of remote memories.

neuroscience↗

bioRxiv2024

Osterix Facilitates Osteocytic Communication by Targeting Connexin43

Osteocytes, terminal-differentiated cells in bone, are now considered as more pivotal regulators of mature bone homeostasis than other bone cells, since they constitute 90- 95% of the bone cell population. Given their non-migratory nature within the mineralized matrix, their unique dendrites are crucial for cell-to-cell communication in response to both intracellular and extracellular stimuli, such as bone fracture or mechanical load. Here, we showed that Osterix (Osx), usually recognized as a specific doorkeeper for osteoblast differentiation during new bone formation marked by collagen type I 1 (Col11), was unexpectedly co-expressed with Col11 in osteocytes within the cortical bone of mice. Deleting Osx in Col11-positive osteocytes disrupted cortical bone structure and osteocytic dendrites in mice, thus impairing transcellular fluid flow and intercellular communication. Conversely, overexpression of Osx in osteocytes enhanced these processes. Furthermore, we identified Connexin43, a critical protein of gap junction channel, was a direct transcriptional target of Osx in regulating dendrites of osteocytes. Pharmacological restoration of Connexin43 levels rescued the dysfunction in Osx-deficient osteocytes both in vitro and in vivo. Taken together, this work demonstrated Osxs distinct role in osteocyte function through maintaining intercellular signaling, which broadened the current understanding of its role in Col11-positive bone cells, extending beyond osteoblasts and bone mineralization, offering new insights into bone diseases such as fracture nonunion or disuse osteoporosis.

cell biology↗

bioRxiv2024

Spatiotemporal Single-Cell Roadmap of Human Skin Wound Healing

Wound healing is vital for human health, yet the details of cellular dynamics and coordination in human wound repair remain largely unexplored. To address this, we conducted single-cell and spatial transcriptomics analyses on human skin and acute wound tissues through inflammation, proliferation, and remodeling phases of wound repair from the same individuals, monitoring the cellular and molecular dynamics of human skin wound healing at an unprecedented spatiotemporal resolution. This singular roadmap reveals the cellular architecture of the wound margin and identifies FOSL1 as a critical driver of re-epithelialization. It shows that pro-inflammatory macrophages and fibroblasts sequentially support keratinocyte migration like a relay race across different healing stages. Comparison with single-cell data from venous and diabetic foot ulcers uncovers a link between failed keratinocyte migration and impaired inflammatory response in chronic wounds. Additionally, comparing human and mouse acute wound transcriptomes underscores the indispensable value of this roadmap in bridging basic research with clinical innovations. HighlightsO_LIA spatiotemporal atlas to explore human in vivo gene expression across wound healing C_LIO_LIWound margin architecture unveils a model for human re-epithelialization C_LIO_LIDistinct healing challenges in venous ulcers and diabetic foot ulcers C_LIO_LIUnique human healing traits emerge in cellular heterogeneity and gene expression C_LI

cell biology↗

bioRxiv2024

Electron tomography visualization of HIV-1 virions trapped by fusion inhibitors to host cells in infected tissues

HIV-1 delivers its genetic material to infect a cell after fusion of the viral and host cell membranes, which takes place after the viral envelope (Env) binds host receptor and co-receptor proteins. Binding of host receptor CD4 to Env results in conformational changes that allow interaction with a host co-receptor (CCR5 or CXCR4). Further conformational rearrangements result in an elongated pre-hairpin intermediate structure in which Env is anchored to the viral membrane by its transmembrane region and to the host cell membrane by its fusion peptide. Although budding virions can be readily imaged by electron tomography (ET) of HIV-1-infected tissues and cultured cells, virions that are fusing (attached to host cells via pre-hairpin intermediates) are not normally visualized, perhaps because the process of membrane fusion is too fast to capture by EM. To image virions during fusion, we used fusion inhibitors to prevent downstream conformational changes in Env that lead to membrane fusion, thereby trapping HIV-1 virions linked to target cells by prehairpin intermediates. ET of HIV-1 pseudovirions bound to CD4+/CCR5+ TZM-bl cells revealed presumptive pre-hairpin intermediates as 2-4 narrow spokes linking a virion to the cell surface. To extend these results to a more physiological setting, we used ET to image tissues and organs derived from humanized bone marrow, liver, thymus (BLT) mice infected with HIV-1 and then treated with CPT31, a high-affinity D-peptide fusion inhibitor linked to cholesterol. Trapped HIV-1 virions were found in all tissues studied (small intestine, mesenteric lymph nodes, spleen, and bone marrow), and spokes representing pre-hairpin intermediates linking trapped virions to cell surfaces were similar in structure and number to those seen in the previous pseudovirus and cultured cell ET study. IMPORTANCETrapped and untrapped HIV-1 virions, both mature and immature, were distinguished by localizing spokes via 3D tomographic reconstructions of HIV-1 infected and fusion-inhibitor treated tissues of humanized mice. The finding of trapped HIV-1 virions in all tissues examined demonstrates a wide distribution of the CPT31 inhibitor, a desirable property for a potential therapeutic. In addition, the presence of virions trapped by spokes, particularly in vascular endothelial cells, demonstrates that fusion inhibitors can be used as markers for potential HIV-1-target cells within tissues, facilitating the mapping of HIV-1 target cells within the complex cellular milieu of infected tissues.

microbiology↗

bioRxiv2024

Long-Range Enhancer Networks Gradually Emerge as Key Regulators During Human Cortical Neurogenesis

The chromatin in the human brain cortex shows more enhancer-enhancer contacts than in macaques and mice, yet the organization of these contacts across cellular states and their mechanisms remain unclear. Here, we developed SCOPE-C, a cost-effective technique designed for mapping DNase I Hypersensitive Sites and their spatial interactions, with the potential for scalability to single-cell resolution. Employing SCOPE-C, we generated a comprehensive chromatin map detailing cis-regulatory elements in four cell types during neurogenesis in human, macaque, and mouse fetal cortex. This map introduces a model of long-range enhancer networks that regulate gene transcription during human cortical neurogenesis. In this model, CTCF-mediated loop extrusion forms stripes of enhancer interaction hubs extending up to 10 Mb in human Excitatory Neurons. Enriched with human-specific enhancers and neuropsychiatric disorder-linked SNPs, these remarkably long-range networks predominantly control EN marker genes, suggesting their critical role in robust gene expression during human cortical neurogenesis.

genomics↗

bioRxiv2024

Synchronous assembly of peptide anisosome

Biomolecular condensates, formed by liquid-liquid phase separation (LLPS) of proteins or the complex of protein and nucleic acids, play key roles in regulating physiological events in biological system. However, the formation of mono-component yet inhomogeneous condensates is limited, and the underlying mechanism remains unclear. Here, we report the symmetrical core-shell structural biomolecular condensates formed through the LLPS by programming a tetra-peptide library. Mechanistic studies reveal that the tryptophan (W) is critical for the formation of core-shell structure because of its stronger homotypical {pi}-{pi} interaction compared with other amino acids, which endow us to modulate the droplets from core-shell to homogeneous structures by encoding the amino acid composition. Using molecular dynamics (MD) simulation and molecular engineering, we find that the inner core of LLPS is composed of dynamic and reversible fibers surrounded by liquid-like shells, resulting in a stable core-shell LLPS. Furthermore, we could control the multiphasic droplet formation by an intrinsic redox reaction or post-translational modification of peptide through phosphorylation, which facilitates the rational design of synthetic LLPS with various applications on demand.

bioengineering↗

bioRxiv2024

Systematic identification of secondary bile acid production genes in global microbiome

Microbial metabolism of bile acids (BAs) is crucial for maintaining homeostasis in vertebrate hosts and environments. Although certain organisms involved in BA metabolism have been identified, a global, comprehensive elucidation of the microbes, metabolic enzymes, and BA remains incomplete. To bridge this gap, we employed hidden Markov models to systematically search in a large-scale and high-quality search library comprising 28,813 RefSeq multi-kingdom microbial complete genomes, which enabled us to construct a secondary bile acid (SBA)-production gene catalog. This catalog greatly expanded the distribution of SBA-production genes across 11 phyla, encompassing bacteria, archaea and fungi, and extended to 14 habitats spanning hosts and environmental contexts. Furthermore, we highlighted the associations between SBAs and gastrointestinal and hepatic disorders, including inflammatory bowel disease, colorectal cancer and nonalcoholic fatty liver disease, further elucidating disease-specific alterations in SBA-production genes. Additionally, we proposed the pig as a particularly suitable animal model for investigating SBA production in humans, given its closely aligned SBA-production gene composition. This gene catalog provides a comprehensive and reliable foundation on microbial BA metabolism for future studies, offering new insights into the microbial contributions to health and disease.

genomics↗

bioRxiv2024

Hepatic Macrophage Migration Inhibitory Factor Promotes Pancreatic Cancer Liver Metastasis in NAFLD

How pathological livers shape tumors, thereby driving pancreatic ductal adenocarcinoma (PDAC) metastasis to the liver, is poorly understood. In the present study, we focus on examining key molecules implicated in this process and assessing their translational significance. We demonstrated that patients with combined non-alcoholic fatty liver disease (NAFLD) have approximately a ninefold increased risk of developing liver metastasis compared to those without NAFLD. In mice model, NAFLD fosters an immunosuppressive microenvironment with increased tumor cell pluripotency and focal adhesion. Mechanistically, NAFLD-induced MIF mediated the progression of PDAC liver metastasis by attracting CD44 positive pancreatic cells. Hepatic MIF knockdown significantly reduced metastases burden with decreased stem-like cancer cells, tumor associated macrophages (TAMs) infiltration and focal adhesion. Targeting the MIF-CD44 axis by either a MIF tautomerase inhibitor, IPG1576, or by CD44 knockdown in tumor cells significantly attenuate liver metastasis of PDAC within the NAFLD context. Patients with PDAC liver metastasis and NAFLD had elevated hepatic MIF expression and increased number of stem-cell like cancer cells. Collectively, our study highlights a pivotal role for MIF-CD44 axis in cancer stemness and offer novel avenues for tailoring therapeutic strategies to individual patients with NAFLD as an underlying condition.

cancer biology↗

bioRxiv2024

scRNA-seq revealed the rules for CDR3 length pairing in TCR beta and alpha chains and BCR heavy and light chains in human and mice

The binding of T cell receptor (TCR)/B cell receptor (BCR) CDR3 with linear or conformational epitopes is a prerequisite for the adaptive immune response. The rules for CDR3 length pairing and the amino acid (AA) distributions in the prioritized rearrangement of the {beta} chain (or heavy chain) and subsequent rearrangement of the chain (or light chain) during the process of germline V(D)J gene rearrangement and self-tolerance selection to form the T- or B-cell CDR3 repertoire are currently unknown. Single-cell VDJ sequencing can provide abundant information on CDR3 sequences in paired chains. In this study, the paired-chain CDR3 sequences of central and peripheral T and B cells in humans and mice were analyzed according to single-cell VDJ sequencing data. This is the first study to find that T cells with {beta} chains longer than paired chains and B cells with heavy chains longer than paired light chains have absolute advantages. The proportion of T cells with length differences of three or more AAs between paired chains in CDR3 in humans was significantly higher than that in mice, and the proportion of B cells with length differences of six or more AAs between paired chains in CDR3 in humans was significantly higher than that in mice. The CDR3 length range of the {beta} chain was narrower than that of the chain, while the heavy chain had a much wider range than the light chain. The CDR3 length in human TCRs and BCRs was greater than that in mice. Extreme length differences were found between paired chains in both human and mouse T and B cells. There were significant differences in the range of pairing length, AA distribution, hydrophobicity, and polarity of the paired-chain CDR3 region in 5 chains ({beta}, , H, {kappa}, and {lambda}). Human TCR and BCR paired CDR3 sequences exhibited greater plasticity than those of mice. This study reveals new ideas about the molecular mechanisms of TCR and BCR responses to different antigenic epitopes. Our innovative findings offer novel perspectives and techniques for examining V(D)J rearrangement and selection mechanisms in T and B cells. These advancements enable us to analyze antigenic epitopes targeted by TCRs and BCRs, and further, to explore the genetic evolution of T and B cell responses across diverse animal species. Graphical AbstractscRNA-seq the TCR and BCR CDR3 repertoires of 35 samples from the central and peripheral tissues of humans and mice. It provides an opportunity to reveal the rules for CDR3 length pairing in TCR beta and alpha chains and BCR heavy and light chains. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=45 SRC="FIGDIR/small/596201v1_ufig1.gif" ALT="Figure 1"> View larger version (14K): org.highwire.dtl.DTLVardef@11982edorg.highwire.dtl.DTLVardef@1e2d1aaorg.highwire.dtl.DTLVardef@33200dorg.highwire.dtl.DTLVardef@7d61b1_HPS_FORMAT_FIGEXP M_FIG C_FIG

immunology↗

bioRxiv2024

Recognition of RNA secondary structures with a programmable peptide nucleic acid-based platform

RNA secondary structures comprise double-stranded (ds) and single-stranded (ss) regions. Antisense peptide nucleic acids (asPNAs) enable the targeting of ssRNAs and weakly formed dsRNAs. Nucleobase-modified dsRNA-binding PNAs (dbPNAs) allow for targeting of relatively stable dsRNAs. A programmable RNA structure-specific targeting strategy is needed for simultaneous recognition of dsRNAs and ssRNAs. Here, we report on combining dbPNAs and asPNAs (designated as daPNAs) for the targeting of dsRNA-ssRNA junctions. Our binding and modeling data suggest that combining traditional asPNA (with a 4-letter code: T, C, A, and G) and dbPNA (with a 4-letter code: T or s2U, L, Q, and E) scaffolds facilitates RNA structure-specific tight binding (nM to M) under physiologically-relevant conditions. We further applied our daPNAs in substrate specific inhibition of Dicer acting on pre-miR-198 in a cell-free assay and regulating ribosomal frameshifting induced by model hairpins in both cell-free and cell culture assays. daPNAs would be a useful platform for developing chemical probes and therapeutic ligands targeting RNA. HighlightO_LIWe demonstrated that sequence- and structure-specific targeting of RNA can be facilitated by nucleobase-modified dsRNA-binding PNAs (dbPNAs) platform in combination with antisense PNAs (asPNAs). We name the novel PNAs as daPNAs. C_LIO_LIdaPNAs can be used in a programmable way for targeting RNAs by formation of a short triplex next to a short duplex at a dsRNA-ssRNA junction. C_LIO_LIWe applied our daPNAs in substrate specific inhibition of Dicer acting on pre-miR-198 in a cell-free assay and regulating ribosomal frameshifting induced by model hairpins in both cell-free and cell culture assays. C_LIO_LIThe daPNAs platform would serve as useful junction-specific molecular glues for the targeting of many biologically important RNA structures in transcriptomes. C_LI

biochemistry↗

bioRxiv2024

Nothing but lies: improving the validity of neural predictors of deception

Deception is a universal human behavior. Yet longstanding skepticism about the validity of measures used to understand the biological mechanisms underlying deceptive behavior has relegated such studies to the scientific periphery. Here we address these fundamental questions by applying novel machine learning methods and functional neuroimaging to signaling games capturing motivated deception in human participants. First, we develop an approach to test for the presence of confounding processes and thereby validate past skepticism by showing that much of the predictive power of neural predictors trained on deception data comes from confounding processes. Second, we show that the presence of confounding signals need not be fatal, and we improve the validity of our neural predictor via a novel machine learning procedure that identifies and removes these confounding signals. Together, these findings point to a scientific approach for studying a neglected class of behavior, with important methodological and societal implications.

neuroscience↗

bioRxiv2024

CD4 downregulation precedes Env expression and protects HIV-1-infected cells from ADCC mediated by non-neutralizing antibodies

HIV-1 envelope glycoprotein (Env) conformation substantially impacts antibody-dependent cellular cytotoxicity (ADCC). Envs from primary HIV-1 isolates adopt a prefusion "closed" conformation, which is targeted by broadly-neutralizing antibodies (bnAbs). CD4 binding drives Env into more "open" conformations, which are recognized by non-neutralizing Abs (nnAbs). To better understand Env-Ab and Env-CD4 interaction in CD4+ T cells infected with HIV-1, we simultaneously measured antibody binding and HIV-1 mRNA expression using multiparametric flow cytometry and RNA-flow fluorescent in situ hybridization (FISH) techniques. We observed that env mRNA is almost exclusively expressed by HIV-1 productively-infected cells that already downmodulated CD4. This suggest that CD4 downmodulation precedes env mRNA expression. Consequently, productively-infected cells express "closed" Envs on their surface, which renders them resistant to nnAbs. Cells recognized by nnAbs were all env mRNA negative, indicating Ab binding through shed gp120 or virions attached to their surface. Consistent with these findings, treatment of HIV-1 infected humanized mice with the ADCC mediating nnAb A32 failed to lower viral replication or reduce the size of the viral reservoir. These findings confirm the resistance of productively-infected CD4+ T cells to nnAbs-mediated ADCC and question the rationale of immunotherapy approaches using this strategy. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=199 SRC="FIGDIR/small/592003v2_ufig1.gif" ALT="Figure 1"> View larger version (30K): org.highwire.dtl.DTLVardef@1c34d91org.highwire.dtl.DTLVardef@11975c0org.highwire.dtl.DTLVardef@81b5beorg.highwire.dtl.DTLVardef@1c2e0b2_HPS_FORMAT_FIGEXP M_FIG C_FIG

microbiology↗

bioRxiv2024

Sacrificing Adaptability for Functionality: The Ivory Tower of Macular Muller Cells

The predilection of many retinal diseases for the macula suggests it may be less resistant to stress than the peripheral retina. Profiling of single-cell level transcriptional changes found that the peripheral retina exhibited more transcriptional changes than the macula in response to stress. One pronounced change was in a subgroup of Muller cells (MCs) that were dominant in the peripheral retina. Genes more abundantly expressed in peripheral MCs were mainly associated with stress responses and were more influenced by light stress. In contrast, genes highly expressed in MCs that predominated in the macula had roles in cellular function and were less influenced by light stress. Metallothionein 1, A Kinase Anchor Protein 12 and MAF BZIP Transcription Factor F were more abundantly expressed in peripheral MCs than in macular MCs. Knockdown of these genes in primary MCs reduced their viability under stress. Our findings indicate that macular MCs are more directed toward maintaining retinal function rather than mounting a stress response when exposed to stress, which may contribute to the maculas vulnerability to degenerative diseases.

neuroscience↗