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Nanoparticle's success as drug delivery systems for cancer treatment has been achieved through passive targeting mechanisms. However, tumor heterogeneity and rapid drug clearance limit the treatment efficacy. Improved outcomes and selective drug release can be achieved by grafting ligands at the surface of nanocarriers that bind molecules overexpressed in the tumor microenvironment (TME). In this work, we developed a docetaxel-loaded nanoemulsions (NEs) binding an anti-netrin-1 monoclonal antibody (NP137) to selectively target the netrin-1 protein overexpressed in many different tumors. The goal is to refine a combined approach utilizing NP137 and docetaxel as an improved tumor-targeting chemotherapeutic agent for addressing triple-negative breast cancer (TNBC). Several factors have been considered for the optimization of the active targeted drug delivery system via the click-chemistry conjugation, as the impact of PEGylated surfactant that stabilize the NEs shell on conjugation efficiency, cytocompatibility with EMT6 cell line and colloidal stability over time of NEs. Results showed that a 660 Da PEG chain length contributed to NEs colloidal stability and had no impact on cell viability or on the antibody binding ability for its ligand after surface conjugation. Moreover, docetaxel was encapsulated into the oily core of NEs, with an encapsulation efficiency of 70 %. To validate our treatment strategy in vivo, the 4T1 murine breast cancer model was used. As a result, the comparison of active-targeted and non-targeted NEs revealed that only active-targeted NE could decrease the tumor growth rate., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Giovanna Lollo reports financial support and equipment, drugs, or supplies were provided by University Claude Bernard Lyon 1 - Campus Rockefeller. Benjamin Gibert reports financial support and equipment, drugs, or supplies were provided by Cancer Research Centre Lyon. Ilaria Marigo reports financial support and equipment, drugs, or supplies were provided by Veneto Oncology Institute. Patrick Mehlen declares to have a coflict of interest as shareholder of Netris Pharma. The other authors declare that they have no financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

In Gram-positive bacteria, cell wall polysaccharides (CWPS) play critical roles in bacterial cell wall homeostasis and bacterial interactions with their immediate surroundings. In lactococci, CWPS consist of two components: a conserved rhamnan embedded in the peptidoglycan layer and a surface-exposed polysaccharide pellicle (PSP), which are linked together to form a large rhamnose-rich CWPS (Rha-CWPS). PSP, whose structure varies from strain to strain, is a receptor for many bacteriophages infecting lactococci. Here, we examined the first two steps of PSP biosynthesis, using in vitro enzymatic tests with lipid acceptor substrates combined with LC-MS analysis, AlfaFold2 modeling of protein 3D-structure, complementation experiments, and phage assays. We show that the PSP repeat unit is assembled on an undecaprenyl-monophosphate (C 55 P) lipid intermediate. Synthesis is initiated by the WpsA/WpsB complex with GlcNAc-P-C 55 synthase activity and the PSP precursor GlcNAc-P-C 55 is then elongated by specific glycosyltransferases that vary among lactococcal strains, resulting in PSPs with diverse structures. Also, we engineered the PSP biosynthesis pathway in lactococci to obtain a chimeric PSP structure, confirming the predicted glycosyltransferase specificities. This enabled us to highlight the importance of a single sugar residue of the PSP repeat unit in phage recognition. In conclusion, our results support a novel pathway for PSP biosynthesis on a lipid-monophosphate intermediate as an extracellular modification of rhamnan, unveiling an assembly machinery for complex Rha-CWPS with structural diversity in lactococci., Competing Interests: Conflicts of interest C. C. is an employee of Alphagraphix (cambillau.alphagraphix@gmail.com). Authors and Alphagraphix declare that they have no competing interests. The funders had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript; or in the decision to publish the results., (Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.)

Lactococcus lactis and Lactococcus cremoris are Gram-positive lactic acid bacteria widely used as starter in milk fermentations. Lactococcal cells are covered with a polysaccharide pellicle (PSP) that was previously shown to act as the receptor for numerous bacteriophages of the Caudoviricetes class. Thus, mutant strains lacking PSP are phage resistant. However, because PSP is a key cell wall component, PSP-negative mutants exhibit dramatic alterations of cell shape and severe growth defects, which limit their technological value. In the present study, we isolated spontaneous mutants with improved growth, from L. cremoris PSP-negative mutants. These mutants grow at rates similar to the wild-type strain, and based on transmission electron microscopy analysis, they exhibit improved cell morphology compared to their parental PSP-negative mutants. In addition, the selected mutants maintain their phage resistance. Whole-genome sequencing of several such mutants showed that they carried a mutation in pbp2b , a gene encoding a penicillin-binding protein involved in peptidoglycan biosynthesis. Our results indicate that lowering or turning off PBP2b activity suppresses the requirement for PSP and ameliorates substantially bacterial fitness and morphology. IMPORTANCE Lactococcus lactis and Lactococcus cremoris are widely used in the dairy industry as a starter culture. As such, they are consistently challenged by bacteriophage infections which may result in reduced or failed milk acidification with associated economic losses. Bacteriophage infection starts with the recognition of a receptor at the cell surface, which was shown to be a cell wall polysaccharide (the polysaccharide pellicle [PSP]) for the majority of lactococcal phages. Lactococcal mutants devoid of PSP exhibit phage resistance but also reduced fitness, since their morphology and division are severely impaired. Here, we isolated spontaneous, food-grade non-PSP-producing L. cremoris mutants resistant to bacteriophage infection with a restored fitness. This study provides an approach to isolate non-GMO phage-resistant L. cremoris and L. lactis strains, which can be applied to strains with technological functionalities. Also, our results highlight for the first time the link between peptidoglycan and cell wall polysaccharide biosynthesis., Competing Interests: The authors declare no conflict of interest.

Oral administration of nanoparticles (NPs) is a promising strategy to overcome solubility and stability issues of many active compounds. However, this route faces major obstacles related to the hostile gastrointestinal (GI) environment, which impairs the efficacy of orally administered nanomedicines. Here, we propose nanocomposites as a promising approach to increase the retention time of NPs in the intestinal tract by using bio- and mucoadhesive matrixes able to protect the cargo until it reaches the targeted area. A microfluidic-based approach has been applied for the production of tailored nanoemulsions (NEs) of about 110 nm, used for the encapsulation of small hydrophobic drugs such as the anti-inflammatory JAK-inhibitor tofacitinib. These NEs proved to be efficiently internalized into a mucus-secreting human intestinal monolayer of Caco-2/HT29-MTX cells and to deliver tofacitinib to subepithelial human THP-1 macrophage-like cells, reducing their inflammatory response. NEs were then successfully encapsulated into alginate hydrogel microbeads of around 300 μm, which were characterized by rheological experiments and dried to create a long-term stable system for pharmaceutical applications. Finally, ex vivo experiments on excised segments of rats' intestine proved the bioadhesive ability of NEs embedded in alginate hydrogels compared to free NEs, showing the advantage that this hybrid system can offer for the treatment of intestinal pathologies.

Rhamnose-rich cell wall polysaccharides (Rha-CWPSs) have emerged as crucial cell wall components of numerous Gram-positive, ovoid-shaped bacteria-including streptococci, enterococci, and lactococci-of which many are of clinical or biotechnological importance. Rha-CWPS are composed of a conserved polyrhamnose backbone with side-chain substituents of variable size and structure. Because these substituents contain phosphate groups, Rha-CWPS can also be classified as polyanionic glycopolymers, similar to wall teichoic acids, of which they appear to be functional homologs. Recent advances have highlighted the critical role of these side-chain substituents in bacterial cell growth and division, as well as in specific interactions between bacteria and infecting bacteriophages or eukaryotic hosts. Here, we review the current state of knowledge on the structure and biosynthesis of Rha-CWPS in several ovoid-shaped bacterial species. We emphasize the role played by multicomponent transmembrane glycosylation systems in the addition of side-chain substituents of various sizes as extracytoplasmic modifications of the polyrhamnose backbone. We provide an overview of the contribution of Rha-CWPS to cell wall architecture and biogenesis and discuss current hypotheses regarding their importance in the cell division process. Finally, we sum up the critical roles that Rha-CWPS can play as bacteriophage receptors or in escaping host defenses, roles that are mediated mainly through their side-chain substituents. From an applied perspective, increased knowledge of Rha-CWPS can lead to advancements in strategies for preventing phage infection of lactococci and streptococci in food fermentation and for combating pathogenic streptococci and enterococci., Competing Interests: Conflict of interests The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this article., (Copyright © 2022 The Authors. Published by Elsevier Inc. All rights reserved.)

Ion sensitive field effect transistors (ISFETs) form a very attractive solution for wearable sensors due to their capacity for ultra-miniaturization, low power operation, and very high sensitivity, supported by complementary metal oxide semiconductor (CMOS) integration. This paper reports for the first time, a multianalyte sensing platform that incorporates high performance, high yield, high robustness, three-dimensional-extended-metal-gate ISFETs (3D-EMG-ISFETs) realized by the postprocessing of a conventional 0.18 μm CMOS technology node. The detection of four analytes (pH, Na + , K + , and Ca 2+ ) is reported with excellent sensitivities (58 mV/pH, -57 mV/dec(Na + ), -48 mV/dec(K + ), and -26 mV/dec(Ca 2+ )) close to the Nernstian limit, and high selectivity, achieved by the use of highly selective ion selective membranes based on postprocessing integration steps aimed at eliminating any significant sensor hysteresis and parasitics. We are reporting simultaneous time-dependent recording of multiple analytes, with high selectivities. In vitro real sweat tests are carried out to prove the validity of our sensors. The reported sensors have the lowest reported power consumption, being capable of operation down to 2 pW/sensor. Due to the ultralow power consumption of our ISFETs, we achieve and report a final four-analyte passive system demonstrator including the readout interface and the remote powering of the ISFET sensors, all powered by an radio frequency (RF) signal.

Wearable systems could offer noninvasive and real-time solutions for monitoring of biomarkers in human sweat as an alternative to blood testing. Recent studies have demonstrated that the concentration of certain biomarkers in sweat can be directly correlated to their concentrations in blood, making sweat a trusted biofluid candidate for noninvasive diagnostics. We introduce a fully on-chip integrated wearable sweat sensing system to track biochemical information at the surface of the skin in real time. This system heterogeneously integrates, on a single silicon chip, state-of-the-art ultrathin body (UTB) fully depleted silicon-on-insulator (FD-SOI) ISFET sensors with a biocompatible microfluidic interface, to deliver a "lab-on-skin" sensing platform. A full process for the fabrication of this system is proposed in this work and is demonstrated by standard semiconductor fabrication procedures. The system is capable of collecting small volumes of sweat from the skin of a human and posteriorly passively driving the biofluid, by capillary action, to a set of functionalized ISFETs for analysis of pH level and Na + and K + concentrations. Drop-casted ion-sensing membranes on different sets of sensors on the same substrate enable multiparameter analysis on the same chip, with small and controlled cross-sensitivities, whereas a miniaturized quasireference electrodes set a stable analyte potential, avoiding the use of a cumbersome external reference electrode. The progress of lab-on-skin technology reported here can lead to autonomous wearable systems enabling real-time continuous monitoring of sweat composition, with applications ranging from medicine to lifestyle behavioral engineering and sports.