Protein micro- and nano-capsules for biomedical applications

Micro- and nano-scale systems have emerged as important tools for developing clinically useful drug delivery systems. In this tutorial review, we discuss the exploitation of biomacromolecules for this purpose, focusing on proteins, polypeptides, nucleic acids and polysaccharides and mixtures thereof as potential building blocks for novel drug delivery systems. We focus on the mechanisms of formation of micro- and nano-scale protein-based capsules and shells, as well as on the functionalization of such structures for use in targeted delivery of bioactive materials. We summarise existing methods for protein-based capsule synthesis and functionalization and highlight future challenges and opportunities for delivery strategies based on biomacromolecules.U.S. is grateful to Professor Aharon Gedanken, Chemistry Department, Bar-Ilan University, Israel, for his support and supervision during her PhD research work. G.J.L.B. is a Royal Society University Research Fellow at the Department of Chemistry, University of Cambridge and an Investigador FCT at the Instituto de Medicina Molecular, Lisboa. We thank Nuno Azoia assistance with the preparation of the figures. The authors thank the European Union Seventh Framework Programme (FP7/20072013) under grant agreement NMP4-LA-2009-228827 NANOFOL

Folic acid-tagged protein nanoemulsions loaded with CORM-2 enhance the survival of mice bearing subcutaneous A20 lymphoma tumors

Folic Acid (FA)-tagged protein nanoemulsions were found to be preferentially internalized on B-cell lymphoma cell line (A20 cell line), which, for the first time, are reported to express folate receptor (FR)-alpha. Carbon monoxide releasing molecule-2 (CORM-2) was incorporated in the oil phase of the initial formulation. FA-functionalized nanoemulsions loaded with CORM-2 exhibited a considerable antitumor effect and an increased survival of BALB/c mice bearing subcutaneous A20 lymphoma tumors. The developed nanoemulsions also demonstrated to be well tolerated by these immunocompetent mice. Thus, the results obtained in this study demonstrate that FA-tagged protein nanoemulsions can be successfully used in cancer therapy, with the important ability to delivery drugs intracellularly.SFRH/BD/81479/2011 and SFRH/BD/81269/2011 scholarships from Fundação para a Ciência e a Tecnologia (FCT). This work has received funding from the European Union Seventh Framework Programme (FP7/2007-2013) under grant agreement NMP4-LA-2009-228827 NANOFOL. This work was supported by FEDER through POFC-COMPETE and by Portuguese funds from FCT through the project PEst-OE/BIA/UI4050/2014

Functionalized protein nanoemulsions by incorporation of chemically modified BSA

The incorporation of bioactive compounds in stealth nanoparticles or nanoemulsions enhances their half-life in systemic circulation and can overcome the problems associated with the free drug. Bovine serum albumin (BSA)-drug conjugates were produced with either methotrexate (MTX), a potent anticancer agent, or vancomycin (VCM), a potent antibiotic. Those conjugates were used to produce functionalized BSA nanoemulsions in a formulation composed by aqueous phase and organic phase. BSA-Folic acid (FA) conjugates were also produced allowing specific folate receptor (FR) mediated targeting of cancer cells (KB cell line). All conjugates had similar effects either in solution or in the form of nanoemulsions: BSA-MTX as anti-proliferative over Caco-2 cell line and BSA-VCM as lower minimum inhibitory concentration (MIC) comparatively to VCM solution on Staphylococcus aureus strain Newman. The production of nanoemulsions using BSA-drug conjugates for obtaining vectors loaded with stabilized drugs offers a good, flexible template for a wide range of medical applications.Ana Loureiro (SFRH/BD/81479/2011) holds a scholarship from Fundacao para a Ciencia e a Tecnologia (FCT). Goncalo J. L. Bernardes is a Royal Society University Research Fellow at the Department of Chemistry, University of Cambridge and an Investigador FCT at the Instituto de Medicina Molecular, Faculdade de Medicina da Universidade de Lisboa. This work has received funding from the European Union Seventh Framework Programme (FP7/2007-2013) under grant agreement NMP4-LA-2009-228827 NANOFOL. This work was supported by FEDER through POFC - COMPETE and by Portuguese funds from FCT through the project PEst-OE/BIA/UI4050/2014

Collagen labelling with an azide-proline chemical reporter in live cells.

We have developed a strategy for selective imaging of collagen in live foetal ovine osteoblasts. Our approach involves the incorporation of an azide-tagged proline in the biosynthesis of collagen followed by labelling using a strain-promoted [3+2] azide-alkyne cycloaddition reaction

Quaternization of Vinyl/Alkynyl Pyridine enables ultrafast cysteine‐selective protein modification and charge modulation

© 2019 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.Quaternized vinyl- and alkynyl-pyridine reagents were shown to react in an ultrafast and selective manner with several cysteine-tagged proteins at near-stoichiometric quantities. We have demonstrated that this method can effectively create a homogenous antibody-drug conjugate that features a precise drug-to-antibody ratio of 2, which was stable in human plasma and retained its specificity towards Her2+ cells. Finally, the developed warhead introduces a +1 charge to the overall net charge of the protein, which enabled us to show that the electrophoretic mobility of the protein may be tuned through the simple attachment of a quaternized vinyl pyridinium reagent at the cysteine residues. We anticipate the generalized use of quaternized vinyl- and alkynyl-pyridine reagents not only for bioconjugation, but also as warheads for covalent inhibition and as tools to profile cysteine reactivity.Funded under the EU Horizon 2020 Programme, Marie Skłodowska-Curie ITN GA No. 675007, the Royal Society (UF110046 and URF\R\180019 to G.J.L.B.), FCT Portugal (iFCT IF/00624/2015 to G.J.L.B. and PhD studentship SFRH/BD/115932/2016 to A.G.), Xunta de Galicia (Galician Plan of research, innovation and growth 2011–2015, ED481B 2014/086-0 and ED481B 2018/007 to M.J.M.), D.G.I. MINECO/FEDER (grants CTQ2015-70524-R and RYC-2013–14706 to G.J.-O. and C.D.N and CTQ2015-67727-R to F.C.), Universidad de la Rioja (FPI PhD studentship to I.C.), FAPESP (BEPE 2015/07509-1 and 2017/13168-8 to B.B.), and by an ERC StG (GA No. 676832).info:eu-repo/semantics/publishedVersio

Accelerating Reaction Rates of Biomolecules by Using Shear Stress in Artificial Capillary Systems.

Funder: Frances and Augustus Newman FoundationFunder: Emmanuel College, University of CambridgeFunder: Biotechnology and Biological Sciences Research CouncilFunder: Centre for Misfolding Diseases, University of CambridgeFunder: Wellcome TrustBiomimetics is a design principle within chemistry, biology, and engineering, but chemistry biomimetic approaches have been generally limited to emulating nature's chemical toolkit while emulation of nature's physical toolkit has remained largely unexplored. To begin to explore this, we designed biophysically mimetic microfluidic reactors with characteristic length scales and shear stresses observed within capillaries. We modeled the effect of shear with molecular dynamics studies and showed that this induces specific normally buried residues to become solvent accessible. We then showed using kinetics experiments that rates of reaction of these specific residues in fact increase in a shear-dependent fashion. We applied our results in the creation of a new microfluidic approach for the multidimensional study of cysteine biomarkers. Finally, we used our approach to establish dissociation of the therapeutic antibody trastuzumab in a reducing environment. Our results have implications for the efficacy of existing therapeutic antibodies in blood plasma as well as suggesting in general that biophysically mimetic chemistry is exploited in biology and should be explored as a research area

Merging the Isonitrile‐Tetrazine (4+1) cycloaddition and the Ugi four‐component reaction into a single multicomponent process

© 2023 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.Multicomponent reactions are of utmost importance at generating a unique, wide, and complex chemical space. Herein we describe a novel multicomponent approach based on the combination of the isonitrile-tetrazine (4+1) cycloaddition and the Ugi four-component reaction to generate pyrazole amide derivatives. The scope of the reaction as well as mechanistic insights governing the 4H-pyrazol-4-imine tautomerization are provided. This multicomponent process provides access to a new chemical space of pyrazole amide derivatives and offers a tool for peptide modification and stapling.This work was supported by a Marie Skłodowska-Curie grant (Agreement No. 101018454) from the European Union's Horizon 2020 research and innovation program. We thank the DFG (post-doctoral fellowship, grant no. 493006134, to A. V. V.), Fundação para a Ciência e a Tecnologia (Ph.D. studentship 2022.09827.BD to A. L. D.) and MCIN/AEI/10.13039/501100011033 (PID2021-125946OB-I00 to G. J. O. and CEX2021-001136-S to CIC bioGUNE).info:eu-repo/semantics/publishedVersio

Platinum-Triggered Bond-Cleavage of Pentynoyl Amide and N-Propargyl Handles for Drug-Activation.

The ability to create ways to control drug activation at specific tissues while sparing healthy tissues remains a major challenge. The administration of exogenous target-specific triggers offers the potential for traceless release of active drugs on tumor sites from antibody-drug conjugates (ADCs) and caged prodrugs. We have developed a metal-mediated bond-cleavage reaction that uses platinum complexes [K2PtCl4 or Cisplatin (CisPt)] for drug activation. Key to the success of the reaction is a water-promoted activation process that triggers the reactivity of the platinum complexes. Under these conditions, the decaging of pentynoyl tertiary amides and N-propargyls occurs rapidly in aqueous systems. In cells, the protected analogues of cytotoxic drugs 5-fluorouracil (5-FU) and monomethyl auristatin E (MMAE) are partially activated by nontoxic amounts of platinum salts. Additionally, a noninternalizing ADC built with a pentynoyl traceless linker that features a tertiary amide protected MMAE was also decaged in the presence of platinum salts for extracellular drug release in cancer cells. Finally, CisPt-mediated prodrug activation of a propargyl derivative of 5-FU was shown in a colorectal zebrafish xenograft model that led to significant reductions in tumor size. Overall, our results reveal a new metal-based cleavable reaction that expands the application of platinum complexes beyond those in catalysis and cancer therapy.EPSRC studentship for Benjamin Stenton

Synthesis, characterization and photoinduced CO-release by manganese(i) complexes

Herein, we report the CO-release activity of three new photoCORMs, two with nonbonding pyridine moieties and one with a benzyl group. The compounds [MnBr(CO)3(bpa-κ2)] (2, where bpa = N-benzyl(2-pyridylmethyl)amine); [MnBr(CO)3(pmpeaκ2)] (3, where pmpea = N-(2-pyridylmethyl)-N’-(2-pyridylethyl)amine) and [MnBr(CO)3(bpea-κ2)] (4, where bpea = N-bis(2- pyridylethyl)amine) were synthesized and characterized by common spectroscopic techniques (UV-Vis, IR). Density functional theory studies were also performed to provide new insights into the M–C bond and to assume the orbitals involved in the absorption transitions. Their CO-release activities were measured both in organic and in physiological media and compared to that of a previously published compound [Mn(CO)3(dpa-κ3)]Br (1, where dpa = N-bis(2- pyridylmethyl)amine). An increase in the number of members of the chelate from five to six, influenced the release of CO, affecting both the binding mode of the ligand and the CO-release process and affecting their potential use as potentials CO release carriers as therapeutic agents