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1.
Methods Mol Biol ; 2622: 173-189, 2023.
Article in English | MEDLINE | ID: mdl-36781760

ABSTRACT

Click chemistry, and particularly azide-alkyne cycloaddition, represents one of the principal bioconjugation strategies that can be used to conveniently attach various ligands to the surface of preformed liposomes. This efficient and chemoselective reaction involves a Cu(I)-catalyzed azide-alkyne cycloaddition which can be performed under mild experimental conditions in aqueous media. Here we describe the application of a model click reaction to the conjugation, in a single step, of unprotected α-1-thiomannosyl ligands, functionalized with an azide group, to liposomes containing a terminal alkyne-functionalized lipid anchor. Excellent coupling yields were obtained in the presence of bathophenanthrolinedisulphonate, a water-soluble copper-ion chelator, acting as catalyst. No vesicle leakage was triggered by this conjugation reaction, and the coupled mannose ligands were exposed at the surface of the liposomes. The major limitation of Cu(I)-catalyzed click reactions is that this type of conjugation is restricted to liposomes made of saturated (phospho)lipids. To circumvent this constraint, an example of alternate copper-free azide-alkyne click reaction has been developed, and it was applied to the anchoring of a biotin moiety that was fully functional and could be therefore quantified. Molecular tools and results are presented here.


Subject(s)
Click Chemistry , Liposomes , Liposomes/chemistry , Click Chemistry/methods , Azides/chemistry , Catalysis , Alkynes/chemistry , Ligands , Cycloaddition Reaction
2.
Bioconjug Chem ; 32(3): 482-496, 2021 03 17.
Article in English | MEDLINE | ID: mdl-33662203

ABSTRACT

Cyclic anhydrides are potent tools for bioconjugation; therefore, they are broadly used in the functionalization of biomolecules and carriers. The pH-dependent stability and reactivity, as well as the physical properties, can be tuned by the structure of the cyclic anhydride used; thus, their application in smart delivery systems has become very important. This review intends to cover the last updates in the use of cyclic anhydrides as pH-sensitive linkers, their differences in reactivity, and the latest applications found in bioconjugation chemistry or chemical biology, and when possible, in drug delivery.


Subject(s)
Anhydrides/chemistry , Cyclization , Drug Delivery Systems , Hydrogen-Ion Concentration , Nanoparticles/chemistry
3.
Molecules ; 23(1)2017 Dec 28.
Article in English | MEDLINE | ID: mdl-29283366

ABSTRACT

The aim of the present research work was the synthesis of molecularly imprinted polymers (MIPs) with a rod-like geometry via "mesophase polymerization". The ternary lyotropic system consisting of sodium dodecyl sulfate (SDS), water, and decanol was chosen to prepare a hexagonal mesophase to direct the morphology of the synthesized imprinted polymers using theophylline, methacrylic acid, and ethylene glycol dimethacrylate as a drug model template, a functional monomer, and a crosslinker, respectively. The obtained molecularly imprinted microrods (MIMs) were assessed by performing binding experiments and in vitro release studies, and the obtained results highlighted good selective recognition abilities and sustained release properties. In conclusion, the adopted synthetic strategy involving a lyotropic mesophase system allows for the preparation of effective MIPs characterized by a rod-like morphology.


Subject(s)
Molecular Imprinting/methods , Polymers/chemistry , Polymers/chemical synthesis , Cross-Linking Reagents/chemistry , Drug Carriers/chemistry , Humans , Methacrylates/chemistry , Particle Size , Polymerization , Sodium Dodecyl Sulfate/chemistry , Solvents/chemistry , Surface Properties , Theophylline/chemistry , Water/chemistry
4.
Int J Pharm ; 530(1-2): 354-363, 2017 Sep 15.
Article in English | MEDLINE | ID: mdl-28743554

ABSTRACT

The potent antitumor effect of α-galactosylceramide (α-GalCer) is based on its recognition by invariant Natural Killer T cells (iNKT) after its capture and presentation by antigen presenting cells including dendritic cells (DCs). Synthetic α-GalCer has already been tested in advanced cancer patients but no or only moderate clinical responses were obtained. To optimize α-GalCer efficacy, we have postulated that alternative formulations impacting its molecular organization in aqueous medium could modify DC uptake and iNKT-based immune responses. To this end, we have developed two strategies: (1) the formulation of α-GalCer in non-cationic liposomes and (2) the synthesis of a water-soluble α-GalCer analogue by anchoring a polyethyleneglycol moiety on its sugar head. The biological activities of these new preparations were compared to that induced by the classically used Polysorbate 20 α-GalCer micelles. Both formulations retained their uptake by DCs and activated iNKT cells both in vitro and in vivo. Despite a lower cytokine production, the formulations induced a potent immune response able to control lung murine carcinoma. In conclusion, it is possible to increase α-GalCer solubility in aqueous solution without limiting its antitumor properties.


Subject(s)
Antineoplastic Agents/chemistry , Galactosylceramides/chemistry , Lung Neoplasms/drug therapy , Lymphocyte Activation/drug effects , Natural Killer T-Cells/drug effects , Animals , Cell Line, Tumor , Drug Carriers/chemistry , Liposomes/chemistry , Lung Neoplasms/immunology , Male , Mice , Mice, Inbred C57BL
5.
Methods Mol Biol ; 1522: 93-106, 2017.
Article in English | MEDLINE | ID: mdl-27837533

ABSTRACT

Click chemistry represents a new bioconjugation strategy that can be used to conveniently attach various ligands to the surface of preformed liposomes. This efficient and chemoselective reaction involves a Cu(I)-catalyzed azide-alkyne cycloaddition which can be performed under mild experimental conditions in aqueous media. Here we describe the application of a model click reaction to the conjugation, in a single step, of unprotected α-1-thiomannosyl ligands, functionalized with an azide group, to liposomes containing a terminal alkyne-functionalized lipid anchor. Excellent coupling yields have been obtained in the presence of bathophenanthroline disulfonate, a water soluble copper-ion chelator, acting as a catalyst. No vesicle leakage is triggered by this conjugation reaction and the coupled mannose ligands are exposed at the surface of the liposomes. The major limitation of Cu(I)-catalyzed click reactions is that this conjugation is restricted to liposomes made of saturated (phospho)lipids. To circumvent that constraint, an example of alternative copper-free azide-alkyne click reaction has been developed. Molecular tools and results are presented here.


Subject(s)
Click Chemistry/methods , Liposomes/chemistry , Copper/chemistry , Ligands , Lipids/chemical synthesis , Lipids/chemistry
6.
Oncotarget ; 7(40): 64942-64956, 2016 10 04.
Article in English | MEDLINE | ID: mdl-27409341

ABSTRACT

DR4 (Death Receptor 4) and DR5 (Death Receptor 5) are two potential targets for cancer therapy due to their ability to trigger apoptosis of cancer cells, but not normal ones, when activated by their cognate ligand TRAIL (TNF related apoptosis-inducing ligand). Therapies based on soluble recombinant TRAIL or agonist antibodies directed against one of the receptors are currently under clinical trials. However, TRAIL-R positive tumor cells are frequently resistant to TRAIL induced apoptosis. The precise mechanisms of this resistance are still not entirely understood. We have previously reported on synthetic peptides that bind to DR5 (TRAILmim/DR5) and induce tumor cell apoptosis in vitro and in vivo. Here, we showed that while hexameric soluble TRAIL is able to efficiently kill the DR5 positive lymphoma Jurkat or the carcinoma HCT116, these cells are resistant to apoptosis induced by the divalent form of TRAILmim/DR5 and are poorly sensitive to apoptosis induced by an anti-DR5 agonist monoclonal antibody. This resistance can be restored by the cross-linking of anti-DR5 agonist antibody but not by the cross-linking of the divalent form of TRAILmim/DR5. Interestingly, the divalent form of TRAILmim/DR5 that induced apoptosis of DR5 positive BJAB cells, acts as an inhibitor of TRAIL-induced apoptosis on Jurkat and HCT116 cells. The rapid internalization of DR5 observed when treated with divalent form of TRAILmim/DR5 could explain the antagonist activity of the ligand on Jurkat and HCT116 cells but also highlights the independence of the mechanisms responsible for internalization and activation when triggering the DR5 apoptotic cascade.


Subject(s)
Immunotherapy/methods , Neoplasms/metabolism , Protein Multimerization , Receptors, TNF-Related Apoptosis-Inducing Ligand/metabolism , TNF-Related Apoptosis-Inducing Ligand/metabolism , Antibodies, Monoclonal/chemistry , Antibodies, Monoclonal/metabolism , Antibodies, Monoclonal/therapeutic use , Antibodies, Monoclonal, Humanized , Apoptosis , HCT116 Cells , Humans , Jurkat Cells , Ligands , Molecular Targeted Therapy , Neoplasms/therapy , Organ Specificity , Receptor Aggregation , Receptors, TNF-Related Apoptosis-Inducing Ligand/immunology , TNF-Related Apoptosis-Inducing Ligand/chemical synthesis , TNF-Related Apoptosis-Inducing Ligand/therapeutic use
7.
Chem Phys Lipids ; 188: 27-36, 2015 May.
Article in English | MEDLINE | ID: mdl-25823428

ABSTRACT

Click-based reactions were conducted at the surface of small unilamellar vesicles (SUVs) to provide onto-vesicle chemistry with efficient innovative ready-for-use tools. For that purpose, four amphiphilic molecules were designed to insert into bilayers while presenting a reactive functional head. In this manner, a dioleylglycero-ethoxy-ethoxy-ethoxy-ethanamine (DOG-PEG4-NH2) was chosen as a common platform while the reactive amine head was converted into several electrophilic functions. Thus, two dioleylglycerol-based cyclooctyne anchors were prepared: cyclooct-1-yn-3-glycolic acid-based anchor (DOG-COA) and 1-fluorocyclooct-2-ynecarboxylic acid-based anchor (DOG-FCOA). The last one differed from the first one in that a fluorine atom reinforces the electrophilic properties of the unsaturated bond. In addition, a third dioleylglycerol-based triphenylphosphine (DOG-PPh3) was synthesized for the first time. These three innovative amphiphilic anchors were designed to react with any azide-based biomolecule following copper-free Huisgen 1,4-cycloaddition and Staudinger ligation, respectively. A fourth anchor bearing a 3,4-dibromomaleimide ring (DOG-DBM) was also unprecedentedly synthesized, to be further substituted by two thiols. Model reactions conducted in solution with either model biotinyl azide or model biotinyl disulfide gave good to total conversions and excellent isolated yields. The four new anchors were inserted into SUVs whose formula is classically used in in vivo biology. Stability and surface overall electrostatic charge were in the expected range and constant over the study. Then, the functionalized liposomes were ligated to biotin-based reagents and the experimental conditions were finely tuned to optimize the conversion. The biotinyl liposomes were demonstrated functional and totally accessible in an affinity test based on biotin scaffold quantification. Finally, DOG-FCOA's reactivity was confronted to that of DOG-DBM in a 'one-pot' orthogonal reaction. (Biotin-S)2 and TAMRA-N3 (tetramethylcarboxyrhodamine azide) were successively conjugated to the liposome suspension in a successful manner. These data implement and reinforce the interest of bioorthogonal click-like reactions onto lipid nanoparticles.


Subject(s)
Click Chemistry , Surface-Active Agents/chemistry , Unilamellar Liposomes/chemistry , Molecular Structure , Surface-Active Agents/chemical synthesis , Unilamellar Liposomes/chemical synthesis
8.
Eur J Med Chem ; 51: 174-83, 2012 May.
Article in English | MEDLINE | ID: mdl-22483966

ABSTRACT

A more complete understanding of the mechanism of action of TLR agonists has fueled the investigation of new synthetic immunoadjuvants. In this context, we designed and synthesized glycolipids of the type Pam(2)Cys-α-Galactose as novel immunoadjuvants. Their synthesis required modifying a hydrophobic tBoc-[2,3-bispalmitoyloxy-(2R)-propyl]-R-cysteinyl moiety, i.e. the minimal structure required for TLR2 agonist activity, by addition of a hydrophilic head, either an α-Galactosylpyranose or an α-Galactosylfuranose to gain respectively Pam(2)CGalp and Pam(2)CGalf. While preparing a carbohydrate building block, an unexpected stereoselectivity was observed during a halide ion-catalytic process on a protected galactofuranose: the alpha anomer was obtained with surprisingly high selectivity (α/ß ratio>9) and with good isolated yield (51%). The TLR2 binding properties of Pam(2)CGalp and Pam(2)CGalf were then fully evaluated. Their efficiency in triggering the proliferation of BALB/c mouse splenocytes was also compared to that of Pam(2)CAG and Pam(3)CAG, two well-established ligands of TLRs. Moreover, the maturation state of murine dendritic cells previously incubated with either Pam(2)CGalp or Pam(2)CGalf was monitored by flow cytometry and compared to that induced by lipopolysaccharide. Pam(2)CGalp and Pam(2)CGalf were found to be equivalent TLR2 agonists, and induced splenocyte proliferation and DC maturation. With very similar activity, Pam(2)CGalp and Pam(2)CGalf were also 10-fold to 100-fold better than Pam(2)CAG and Pam(3)CAG at inducing B cell proliferation. This represents the first time a glucidic head has been added to the tBoc-[2,3-bispalmitoyloxy-(2R)-propyl]-R-cysteinyl moiety whilst maintaining the immunomodulating activity. This should greatly enrich the data available on Pam(2)C structure/activity relationships.


Subject(s)
Adjuvants, Immunologic/chemistry , Adjuvants, Immunologic/metabolism , Chemistry Techniques, Synthetic , Galactose/chemistry , Glycolipids/chemistry , Glycolipids/metabolism , Toll-Like Receptor 2/metabolism , Adjuvants, Immunologic/chemical synthesis , Adjuvants, Immunologic/pharmacology , Animals , Cell Line , Female , Glycolipids/chemical synthesis , Glycolipids/pharmacology , Humans , Ligands , Mice , Structure-Activity Relationship , Toll-Like Receptor 2/agonists
9.
J Gene Med ; 12(6): 491-500, 2010 Jun.
Article in English | MEDLINE | ID: mdl-20527042

ABSTRACT

BACKGROUND: Nonviral gene therapy still suffers from low efficiency. Methods that would lead to higher gene expression level of longer duration would be a major advance in this field. Lipidic vectors and physical methods have been investigated separately, and both induced gene expression improvement. METHODS: We sought to combine both chemical and physical methods. Cationic or anionic lipids can potentially destabilize the cell membrane and could consequently enhance gene delivery by a physical method such as electrotransfer. A plasmid model encoding luciferase was used, either free or associated with differently-charged lipoplexes before electrotransfer. RESULTS: Electrotransfer alone strongly enhanced gene expression after intramuscular and intradermal injection of naked DNA. On the other hand, cationic and anionic lipoplex formulations decreased gene expression after electrotransfer, whereas poorly-charged thiourea-based complexes, brought no benefit. Pre-injection of the lipids, followed by administration of naked DNA, did not modified gene expression induced by electroporation in the skin. CONCLUSIONS: The results obtained in the present study suggest that packing of DNA plasmid in lipoplexes strongly decreases the efficiency of gene electrotransfer, independently of the lipoplex charge. Non-aggregating complexes, such as poorly-charged thiourea-based complexes, should be preferred to increase DNA release.


Subject(s)
Cations/chemistry , Electroporation/methods , Gene Transfer Techniques , Liposomes/chemistry , Transfection , Animals , CHO Cells , Cations/metabolism , Cricetinae , Cricetulus , DNA/chemistry , Female , Liposomes/metabolism , Mice , Mice, Inbred BALB C , Muscle, Skeletal/cytology , Muscle, Skeletal/physiology , Plasmids/chemistry , Plasmids/genetics , Skin/cytology , Skin/metabolism
10.
Bioorg Med Chem Lett ; 20(6): 1869-72, 2010 Mar 15.
Article in English | MEDLINE | ID: mdl-20172719

ABSTRACT

Four novel water-soluble lipid immunoadjuvants were designed, synthesized and characterized by MS and NMR. They all induce mouse dendritic cell maturation and B cell proliferation. We demonstrate that in spite of the chemical modification, the four compounds remain TLR2 agonists.


Subject(s)
Adjuvants, Immunologic/pharmacology , B-Lymphocytes/cytology , Cell Proliferation/drug effects , Dendritic Cells/cytology , Lipids/pharmacology , Toll-Like Receptor 2/metabolism , Animals , Magnetic Resonance Spectroscopy , Mass Spectrometry , Mice , Solubility , Water
11.
Bioorg Med Chem Lett ; 18(12): 3628-31, 2008 Jun 15.
Article in English | MEDLINE | ID: mdl-18513963

ABSTRACT

Three synthesized series of compounds based on a thiazolidine core allowed identification of potent inhibitors of thymidylate synthase X. The evaluation of the catalytic activity of the enzyme in the presence of these molecules revealed two distinct classes of compounds that inhibit ThyX with submicromolar concentrations, which could lead, after optimization, to effective inhibitors with potential biomedical interest.


Subject(s)
Enzyme Inhibitors/chemical synthesis , Enzyme Inhibitors/pharmacology , Thiazolidines/chemical synthesis , Thiazolidines/pharmacology , Thymidylate Synthase/antagonists & inhibitors , Drug Design , Drug Evaluation, Preclinical , Enzyme Inhibitors/chemistry , Molecular Conformation , Stereoisomerism , Structure-Activity Relationship , Thiazolidines/chemistry , Thymidylate Synthase/chemistry , Time Factors
12.
Bioconjug Chem ; 18(2): 484-93, 2007.
Article in English | MEDLINE | ID: mdl-17373770

ABSTRACT

A DNA-transfection protocol has been developed that makes use of thiourea non-cationic synthetic lipid, N-[1,3-bis(carbamothioylamino)propan-2-yl]-2-(dialkycarbamoylmethoxy)acetamide. It was found that these new compounds could be formulated without helper lipid and that the N-decanoyl and N-lauryl derivatives transfected B16 cells in the presence of serum with an efficiency at the same level as cationic lipids, under identical conditions. In vivo transfection using intratumoral injection was also investigated. It was found that compounds 18c and 19 showed an efficiency of the same magnitude as naked DNA and cationic lipid.


Subject(s)
DNA/administration & dosage , Gene Transfer Techniques , Lipids/chemistry , Melanoma, Experimental/genetics , Thiourea/chemistry , Animals , Cations , DNA/chemistry , Lipids/chemical synthesis , Liposomes , Luciferases/genetics , Luciferases/metabolism , Melanoma, Experimental/metabolism , Mice , Mice, Inbred C57BL , Plasmids/administration & dosage , Thiourea/chemical synthesis , Transfection , Tumor Cells, Cultured
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