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Therapeutic antibodies (Abs) which act on a broader range of epitopes may provide more durable protection against the genetic drift of a target, typical of viruses or tumors. When these Abs exist concurrently on the targeted antigen, several mechanisms of action (MoAs) can be engaged, boosting therapeutic potency. This study selected combinations of four and five Abs with non- or partially overlapping epitopes to the SARS-CoV-2 spike glycoprotein, on or outside the crucial receptor binding domain (RBD), to offer resilience to emerging variants and trigger multiple MoAs. The combinations were derived from a pool of unique-sequence scFv Ab fragments retrieved from two SARS-CoV-2-naïve human phage display libraries. Following recombinant expression to full-length human IgG1 candidates, a biolayer interferometric analysis mapped epitopes to bins and confirmed that up to four Abs from across the bins can exist simultaneously on the spike glycoprotein trimer. Not all the bins of Abs interfered with the spike protein binding to angiotensin converting enzyme 2 (ACE2) in competitive binding assays, nor neutralized the pseudovirus or authentic virus in vitro, but when combined in vivo, their inclusion resulted in a much stronger viral clearance in the lungs of intranasally challenged hamsters, compared to that of those treated with mono ACE2 blockers. In addition, the Ab mixtures activated in vitro reporter cells expressing Fc-gamma receptors (FcγRs) involved in antibody-dependent cellular cytotoxicity (ADCC) and phagocytosis (ADCP). The best four-Ab combination neutralized seventeen variants of concern from Wuhan-Hu1 to Omicron BA.4/BA.5 in vitro.

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The shortage of organs for transplantation is a global crisis, with an increasing demand and an inadequate supply of organ donors. The convergence of biology and engineering has led to the emergence of 3D bioprinting, which enables the precise and customizable construction of biological structures. Various 3D bioprinting techniques include inkjet printing, extrusion printing, and laser-assisted bioprinting (LAB). Although it has the potential for many benefits, 3D bioprinting comes with its own set of challenges and requirements, specifically associated with the bioprinting of various tissues. The challenges of bioprinting include issues with cells, bioinks, and bioprinters, as well as ethical concerns, clinical efficacy, and cost-effectiveness, making it difficult to integrate 3D bioprinting into widespread clinical practice. Three-dimensional bioprinting holds great promise in addressing the organ shortage crisis, and its applications extend beyond organ transplantation to include drug screening, disease modeling, and regenerative medicine. However, further research is needed to overcome the technical, biological, and ethical challenges associated with 3D bioprinting, paving the way for its widespread clinical implementation. This article discusses the processes and challenges of bioprinting as well as the current research direction in the field.

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Due to the current relevance of pulmonary toxicology (with focus upon air pollution and the inhalation of hazardous materials), it is important to further develop and implement physiologically relevant models of the entire respiratory tract. Lung model development has the aim to create human relevant systems that may replace animal use whilst balancing cost, laborious nature and regulatory ambition. There is an imperative need to move away from rodent models and implement models that mimic the holistic characteristics important in lung function. The purpose of this review is therefore, to describe and identify the various alternative models that are being applied towards assessing the pulmonary toxicology of inhaled substances, as well as the current and potential developments of various advanced models and how they may be applied towards toxicology testing strategies. These models aim to mimic various regions of the lung, as well as implementing different exposure methods with the addition of various physiologically relevent conditions (such as fluid-flow and dynamic movement). There is further progress in the type of models used with focus on the development of lung-on-a-chip technologies and bioprinting, as well as and the optimization of such models to fill current knowledge gaps within toxicology.

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CD157 acts as a receptor, regulating leukocyte trafficking and the binding of extracellular matrix components. However, the expression pattern and the role of CD157 in human blood (BEC) and the lymphatic endothelial cells (LEC) of human dermal microvascular cells (HDMEC), remain elusive. We demonstrated constitutive expression of CD157 on BEC and LEC, in fetal and juvenile/adult skin, in situ, as well as in isolated HDMEC. Interestingly, CD157 epitopes were mostly localized on BEC, co-expressing high levels of CD31 (CD31High), as compared to CD31Low BEC, whereas the podoplanin expression level on LEC did not affect CD157. Cultured HDMEC exhibited significantly higher numbers of CD157-positive LEC, as compared to BEC. Interestingly, separated CD157- and CD157+ HDMEC demonstrated no significant differences in clonal expansion in vitro, but they showed distinct expression levels of cell adhesion molecules, before and after cytokine stimulation in vitro. In particular, we proved the enhanced and specific adherence of CD11b-expressing human blood myeloid cells to CD157+ HDMEC fraction, using an in vitro immune-binding assay. Indeed, CD157 was also involved in chemotaxis and adhesion of CD11b/c monocytes/neutrophils in prevascularized dermo-epidermal skin substitutes (vascDESS) in vivo. Thus, our data attribute specific roles to endothelial CD157, in the regulation of innate immunity during inflammation.

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Heavy metal/metalloids (HMs) and polycyclic aromatic hydrocarbons (PAHs) in soil have caused serious environmental problems, compromised agriculture quality, and have detrimental effects on all forms of life including humans. There is a need to develop appropriate and effective remediation methods to resolve combined contaminated problems. Although conventional technologies exist to tackle contaminated soils, application of biochar as an effective renewable adsorbent for enhanced bioremediation is considered by many scientific researchers as a promising strategy to mitigate HM/PAH co-contaminated soils. This review aims to: (i) provide an overview of biochar preparation and its application, and (ii) critically discuss and examine the prospects of (bio)engineered biochar for enhancing HMs/PAHs co-remediation efficacy by reducing their mobility and bioavailability. The adsorption effectiveness of a biochar largely depends on the type of biomass material, carbonisation method and pyrolysis conditions. Biochar induced soil immobilise and remove metal ions via various mechanisms including electrostatic attractions, ion exchange, complexation and precipitation. PAHs remediation mechanisms are achieved via pore filling, hydrophobic effect, electrostatic attraction, hydrogen bond and partitioning. During last decade, biochar engineering (modification) via biological and chemical approaches to enhance contaminant removal efficiency has garnered greater interests. Hence, the development and application of (bio)engineered biochars in risk management, contaminant management associated with HM/PAH co-contaminated soil. In terms of (bio)engineered biochar, we review the prospects of amalgamating biochar with hydrogel, digestate and bioaugmentation to produce biochar composites.

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Mammalian post-implantation development comprises the coordination of complex lineage decisions and morphogenetic processes shaping the embryo. Despite technological advances, a comprehensive understanding of the dynamics of these processes and of the self-organization capabilities of stem cells and their descendants remains elusive. Building synthetic embryo-like structures from pluripotent embryonic stem cells in vitro promises to fill these knowledge gaps and thereby may prove transformative for developmental biology. Initial efforts to model the post-implantation embryo resulted in structures with compromised morphology (gastruloids). Recent approaches employing modified culture media, an extracellular matrix surrogate or extra-embryonic stem cells, however, succeeded in establishing embryo-like architecture. For example, embedding of gastruloids in Matrigel unlocked self-organization into trunk-like structures with bilateral somites and a neural tube-like structure, together with gut tissue and primordial germ cell-like cells. In this review, we describe the currently available models, discuss how these can be employed to acquire novel biological insights, and detail the imminent challenges for improving current models by in vitro engineering.

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The epidermal growth factor receptor (EGFR) pathway functions through the autocrine or paracrine activation of cellular EGFR by a number of transmembrane ligands. Amplified or mutant EGFR can lead to tumour formation due to increased cell proliferation, growth, migration and survival signals. These oncogenic effects were thought to be confined to aberrant cells hosting genetic alterations in EGFR. However, in the past decade, numerous studies identified that tumour cells could harness extracellular vesicles (EVs) to disseminate EGFR, mutant EGFR, phosphorylated EGFR and EGFR ligands to local and distant cells. This functions to impart a pro-tumourigenic phenotype in recipient cells. EVs play an essential role in intracellular communication, through receptor signalling or the release of their intra-vesicular content into recipient cells. This review will discuss the role of EVs delivering EGFR or EGFR ligands either to or from tumour cells and how this can promote metastases, pre-metastatic niche formation, osteoclastogenesis, angiogenesis and immune modulation in cancer. We will examine how circulating EVs positive for EGFR may be exploited as diagnostic, prognostic or therapeutic markers in cancers including breast, lung, glioblastoma, ovarian and prostate. Finally, we will explore recent breakthroughs in bio-engineering EVs with EGFR targeting abilities for targeted drug delivery.

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The structural and physiological complexity of currently available liver organoids is limited, thereby reducing their relevance for drug studies, disease modelling, and regenerative therapy. In this study we combined mouse liver progenitor cells (LPCs) with mouse liver sinusoidal endothelial cells (LSECs) to generate hepatobiliary organoids with liver-specific vasculature. Organoids consisting of 5x103 cells were created from either LPCs, or a 1:1 combination of LPC/LSECs. LPC organoids demonstrated mild hepatobiliary differentiation in vitro with minimal morphological change; in contrast LPC/LSEC organoids developed clusters of polygonal hepatocyte-like cells and biliary ducts over a 7 day period. Hepatic (albumin, CPS1, CYP3A11) and biliary (GGT1) genes were significantly upregulated in LPC/LSEC organoids compared to LPC organoids over 7 days, as was albumin secretion. LPC/LSEC organoids also had significantly higher in vitro viability compared to LPC organoids. LPC and LPC/LSEC organoids were transplanted into vascularised chambers created in Fah-/-/Rag2-/-/Il2rg-/- mice (50 LPC organoids, containing 2.5x105 LPCs, and 100 LPC/LSEC organoids, containing 2.5x105 LPCs). At 2 weeks, minimal LPCs survived in chambers with LPC organoids, but robust hepatobiliary ductular tissue was present in LPC/LSEC organoids. Morphometric analysis demonstrated a 115-fold increase in HNF4α+ cells in LPC/LSEC organoid chambers (17.26 ± 4.34 cells/mm2 vs 0.15 ± 0.15 cells/mm2, p = 0.018), and 42-fold increase in Sox9+ cells in LPC/LSEC organoid chambers (28.29 ± 6.05 cells/mm2 vs 0.67 ± 0.67 cells/mm2, p = 0.011). This study presents a novel method to develop vascularised hepatobiliary organoids, with both in vitro and in vivo results confirming that incorporating LSECs with LPCs into organoids significantly increases the differentiation of hepatobiliary tissue within organoids and their survival post-transplantation.

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BACKGROUND: Searching for a substitute donor corneal is a hotspot for treating fungal corneal ulcer. OBJECTIVE: To Investigate the clinical effect of bio-engineering cornea and donor cornea on treating fungal corneal ulcer. METHODS: Forty-four cases (44 eyes) of fungal corneal in General Hospital of Northern Theater Command were enrolled, and were randomized into two groups, followed by underwent lamellar keratoplasty using acellular porcine corneal matrix (bio-engineering group, n=22) and human donor cornea (donor group, n=22). The patients were followed up for 12 months. The control rate of infection, visual acuity, graft transparency, epithelizatlon time and complications were observed In both groups. The study was approved by the Ethical Committee of General Hospital of Northern Theater Command, approval No. K(2018)05. RESULTS AND CONCLUSION: (1) The control rate of Infection showed no significant difference between two groups (91%, 91%, P > 0.05). (2) The visual acuity in both groups was improved with time. The visual acuity in the donor group was significantly better than that in the bio-engineering group at 12 months after surgery (P 0.05). (4) The epithelization time showed no significant difference [(6.6±2.0) days, (6.7±1.9) days, P > 0.05]. (5) There was no significant difference In the Incidence of delayed healing of corneal epithelium, rejection reaction of graft, neovascularization, or recurrence between two group (P > 0.05). The rate of graft dissolved In the bio-engineering group was significantly higher than that In the donor group (32%, 8%, P < 0.05). (6) In summary, bio-engineering cornea used for lamellar keratoplasty holds significant efficacy, high safety and good prognosis in the treatment of fungal cornea ulcer, which may as substitute when donor cornea is deficient.

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This work aims at developing an adequate theoretical basis for comparing assimilation of the ancestral C3 pathway with CO2 concentrating mechanisms (CCM) that have evolved to reduce photorespiratory yield losses. We present a novel model for C3 , C2 , C2  + C4 and C4 photosynthesis simulating assimilatory metabolism, energetics and metabolite traffic at the leaf level. It integrates a mechanistic description of light reactions to simulate ATP and NADPH production, and a variable engagement of cyclic electron flow. The analytical solutions are compact and thus suitable for larger scale simulations. Inputs were derived with a comprehensive gas-exchange experiment. We show trade-offs in the operation of C4 that are in line with ecophysiological data. C4 has the potential to increase assimilation over C3 at high temperatures and light intensities, but this benefit is reversed under low temperatures and light. We apply the model to simulate the introduction of progressively complex levels of CCM into C3 rice, which feeds > 3.5 billion people. Increasing assimilation will require considerable modifications such as expressing the NAD(P)H Dehydrogenase-like complex and upregulating cyclic electron flow, enlarging the bundle sheath, and expressing suitable transporters to allow adequate metabolite traffic. The simpler C2 rice may be a desirable alternative.

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Morphogenesis involves interactions of asymmetric cell populations to form complex multicellular patterns and structures comprised of distinct cell types. However, current methods to model morphogenic events lack control over cell-type co-emergence and offer little capability to selectively perturb specific cell subpopulations. Our in vitro system interrogates cell-cell interactions and multicellular organization within human induced pluripotent stem cell (hiPSC) colonies. We examined effects of induced mosaic knockdown of molecular regulators of cortical tension (ROCK1) and cell-cell adhesion (CDH1) with CRISPR interference. Mosaic knockdown of ROCK1 or CDH1 resulted in differential patterning within hiPSC colonies due to cellular self-organization, while retaining an epithelial pluripotent phenotype. Knockdown induction stimulates a transient wave of differential gene expression within the mixed populations that stabilized in coordination with observed self-organization. Mosaic patterning enables genetic interrogation of emergent multicellular properties, which can facilitate better understanding of the molecular pathways that regulate symmetry-breaking during morphogenesis.

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We created APC-mimetic synthetic substrates to study the impact of ligand clustering on T cell activation and spreading. The substrates exhibit antibodies directed against the TCR-complex in the form of a patterned array of sub micrometric dots surrounded by a fluid supported lipid bilayer (SLB) which may itself be functionalized with another bio-molecule. We show that for T cell adhesion mediated by T cell receptor (TCR) alone, in the patterned, but not in the corresponding homogeneous controls, the TCR, ZAP-70 and actin are present in the form of clusters or patches that co-localize with the ligand-dots. However, global cell scale parameters like cell area and actin distribution are only weakly impacted by ligand clustering. In presence of ICAM-1 - the ligand of the T cell integrin LFA-1 - on the SLB, the TCR is still clustered due to the patterning of its ligands, but now global parameters are also impacted. The actin organization changes to a peripheral ring, resembling the classical actin distribution seen on homogeneous substrates, the patterned membrane topography disappears and the membrane is flat, whereas the cell area increases significantly. These observations taken together point to a possible pivotal role for LFA-1 in amplifying the effect of TCR-clustering. No such effect is evident for co-engagement of CD28, affected via its ligand B7.2. Unlike on ICAM-1, on B7.2 cell spreading and actin organization are similar for homogeneous and patterned substrates. However, TCR and ZAP-70 clusters are still formed in the patterned case. These results indicate complementary role for LFA-1 and CD28 in the regulation and putative coupling of TCR micro-clusters to actin. The engineered substrates presented here clearly have the potential to act as platform for fundamental research in immune cell biology, as well as translational analyses in immunotherapy, for example to screen molecules for their role in T cell adhesion/activation.

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Wounds are of a variety of types and each category has its own distinctive healing requirements. This realization has spurred the development of a myriad of wound dressings, each with specific characteristics. It is unrealistic to expect a singular dressing to embrace all characteristics that would fulfill generic needs for wound healing. However, each dressing may approach the ideal requirements by deviating from the 'one size fits all approach', if it conforms strictly to the specifications of the wound and the patient. Indeed, a functional wound dressing should achieve healing of the wound with minimal time and cost expenditures. This article offers an insight into several different types of polymeric materials clinically used in wound dressings and the events taking place at cellular level, which aid the process of healing, while the biomaterial dressing interacts with the body tissue. Hence, the significance of using synthetic polymer films, foam dressings, hydrocolloids, alginate dressings, and hydrogels has been reviewed, and the properties of these materials that conform to wound-healing requirements have been explored. A special section on bioactive dressings and bioengineered skin substitutes that play an active part in healing process has been re-examined in this work.

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The oviduct was long considered a largely passive conduit for gametes and embryos. However, an increasing number of studies into oviduct physiology have demonstrated that it specifically and significantly influences gamete interaction, fertilization and early embryo development. While oviduct epithelial cell (OEC) function has been examined during maintenance in conventional tissue culture dishes, cells seeded into these two-dimensional (2-D) conditions suffer a rapid loss of differentiated OEC characteristics, such as ciliation and secretory activity. Recently, three-dimensional (3-D) cell culture systems have been developed that make use of cell inserts to create basolateral and apical medium compartments with a confluent epithelial cell layer at the interface. Using such 3-D culture systems, OECs can be triggered to redevelop typical differentiated cell properties and levels of tissue organization can be developed that are not possible in a 2-D culture. 3-D culture systems can be further refined using new micro-engineering techniques (including microfluidics and 3-D printing) which can be used to produce 'organs-on-chips', i.e. live 3-D cultures that bio-mimic the oviduct. In this review, concepts for designing bio-mimic 3-D oviduct cultures are presented. The increased possibilities and concomitant challenges when trying to more closely investigate oviduct physiology, gamete activation, fertilization and embryo production are discussed.

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Vitamin C participates in several physiological processes, among others, immune stimulation, synthesis of collagen, hormones, neurotransmitters, and iron absorption. Severe deficiency leads to scurvy, whereas a limited vitamin C intake causes general symptoms, such as increased susceptibility to infections, fatigue, insomnia, and weight loss. Surprisingly vitamin C deficiencies are spread in both developing and developed countries, with the latter actually trying to overcome this lack through dietary supplements and food fortification. Therefore new strategies aimed to increase vitamin C in food plants would be of interest to improve human health. Interestingly, plants are not only living bioreactors for vitamin C production in optimal growing conditions, but also they can increase their vitamin C content as consequence of stress conditions. An overview of the different approaches aimed at increasing vitamin C level in plant food is given. They include genotype selection by "classical" breeding, bio-engineering and changes of the agronomic conditions, on the basis of the emerging concepts that plant can enhance vitamin C synthesis as part of defense responses.

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@#ObjectiveTo study the effects on growth characteristics of cells mutated by outer space. Methods5 tumor cell lines and 1 bio-pharmaceutical cell line were carried in the recoverable satellite No.18 and returned after 18 days flying in outer space.The cell living systems were utilized in passive carrying. Some survival cells were monocoloned, and the experimental methods such as cell morphological observation,MTT assay and FACS were used for analysis of cell growth characteristics. ResultsThe survival cell rates of tumor cell lines and bio-pharmaceutical cells were markedly different. Compared with the control group, mutated cells appeared to have multiple cell morphological changes and the cell number of G1 phase was increased markedly (P<0.05). Growth rate in mutated cells were varied without specific discipline. ConclusionEffects of outer space on growth characteristics were complicated and multiplex in mutated cells,which were not all heredity in further passage. The differences of the monoclonal cell lines provide the potential to obtain optimizing cell lines by screen.