RESUMEN
Liposomes are one of the most important drug delivery vectors, nowadays used in clinics. In general, polyethylene glycol (PEG) is used to ensure the stealth properties of the liposomes. Here, we have employed hydrophilic, biocompatible and highly non-fouling N-(2-hydroxypropyl) methacrylamide (HPMA)-based copolymers containing hydrophobic cholesterol anchors for the surface modification of liposomes, which were prepared by the method of lipid film hydration and extrusion through 100 nm polycarbonate filters. Efficient surface modification of liposomes was confirmed by transmission electron microscopy, atomic force microscopy, and gradient ultracentrifugation. The ability of long-term circulation in the vascular bed was demonstrated in rabbits after i.v. application of fluorescently labelled liposomes. Compared to PEGylated liposomes, HPMA-based copolymer-modified liposomes did not induce specific antibody formation and did not activate murine and human complement. Compared with PEGylated liposomes, HPMA-based copolymer-modified liposomes showed a better long-circulating effect after repeated administration. HPMA-based copolymer-modified liposomes thus represent suitable new candidates for a generation of safer and improved liposomal drug delivery platforms.
Asunto(s)
Interacciones Hidrofóbicas e Hidrofílicas , Liposomas , Polietilenglicoles , Propiedades de Superficie , Animales , Conejos , Ratones , Polietilenglicoles/química , Humanos , Activación de Complemento/efectos de los fármacos , Acrilamidas/química , Colesterol/química , Colesterol/sangre , Sistemas de Liberación de Medicamentos , Masculino , Polímeros/químicaRESUMEN
New synthetic aminooxy lipid was designed and synthesized as a building block for the formulation of functionalised nanoliposomes (presenting onto the outer surface of aminooxy groups) by microfluidic mixing. Orthogonal binding of cellular mannan (Candida glabrata (CCY 26-20-1) onto the outer surface of functionalised nanoliposomes was modified by orthogonal binding of reducing termini of mannans to oxime lipids via a click chemistry reaction based on aminooxy coupling (oxime ligation). The aminooxy lipid was proved as a suitable active component for preparation of functionalised nanoliposomes by the microfluidic mixing method performed with the instrument NanoAssemblr™. This "on-chip technology" can be easily scaled-up. The structure of mannan-liposomes was visualized by transmission and scanning electron microscopy, including immunogold staining of recombinant mannan receptor bound onto mannosylated-liposomes. The observed structures are in a good correlation with data obtained by DLS, NTA, and TPRS methods. In vitro experiments on human and mouse dendritic cells demonstrate selective internalisation of fluorochrome-labelled mannan-liposomes and their ability to stimulate DC comparable to lipopolysaccharide. We describe a potentially new drug delivery platform for mannan receptor-targeted antimicrobial drugs as well as for immunotherapeutics. Furthermore, the platform based on mannans bound orthogonally onto the surface of nanoliposomes represents a self-adjuvanted carrier for construction of liposome-based recombinant vaccines for both systemic and mucosal routes of administration.
Asunto(s)
Células Dendríticas/inmunología , Lectinas Tipo C/inmunología , Liposomas/inmunología , Mananos/inmunología , Lectinas de Unión a Manosa/inmunología , Nanopartículas/química , Receptores de Superficie Celular/inmunología , Adyuvantes Inmunológicos/farmacología , Animales , Antígenos de Superficie/metabolismo , Candida glabrata/química , Química Clic , Humanos , Hidroxilaminas/síntesis química , Hidroxilaminas/química , Lípidos/síntesis química , Lípidos/química , Liposomas/química , Liposomas/farmacología , Mananos/química , Mananos/farmacología , Receptor de Manosa , Ratones Endogámicos BALB C , Microfluídica/métodos , Tamaño de la PartículaRESUMEN
Fatty acyl analogues of muramyldipeptide (MDP) (abbreviated N-L18 norAbuGMDP, N-B30 norAbuGMDP, norAbuMDP-Lys(L18), norAbuMDP-Lys(B30), norAbuGMDP-Lys(L18), norAbuGMDP-Lys(B30), B30 norAbuMDP, L18 norAbuMDP) are designed and synthesized comprising the normuramyl-l-α-aminobutanoyl (norAbu) structural moiety. All new analogues show depressed pyrogenicity in both free (micellar) state and in liposomal formulations when tested in rabbits in vivo (sc and iv application). New analogues are also shown to be selective activators of NOD2 and NLRP3 (inflammasome) in vitro but not NOD1. Potencies of NOD2 and NLRP3 stimulation are found comparable with free MDP and other positive controls. Analogues are also demonstrated to be effective in stimulating cellular proliferation when the sera from mice are injected sc with individual liposome-loaded analogues, causing proliferation of bone marrow-derived GM-progenitors cells. Importantly, vaccination nanoparticles prepared from metallochelation liposomes, His-tagged antigen rOspA from Borrelia burgdorferi, and lipophilic analogue norAbuMDP-Lys(B30) as adjuvant, are shown to provoke OspA-specific antibody responses with a strong Th1-bias (dominance of IgG2a response). In contrast, the adjuvant effects of Alum or parent MDP show a strong Th2-bias (dominance of IgG1 response).
Asunto(s)
Acetilmuramil-Alanil-Isoglutamina/análogos & derivados , Acetilmuramil-Alanil-Isoglutamina/farmacología , Adyuvantes Inmunológicos/farmacología , Antígenos de Superficie/farmacología , Proteínas de la Membrana Bacteriana Externa/farmacología , Vacunas Bacterianas/farmacología , Borrelia burgdorferi/inmunología , Lipoproteínas/farmacología , Acetilmuramil-Alanil-Isoglutamina/química , Acetilmuramil-Alanil-Isoglutamina/inmunología , Adyuvantes Inmunológicos/química , Animales , Formación de Anticuerpos , Antígenos de Superficie/química , Antígenos de Superficie/inmunología , Proteínas de la Membrana Bacteriana Externa/química , Proteínas de la Membrana Bacteriana Externa/inmunología , Vacunas Bacterianas/química , Vacunas Bacterianas/inmunología , Femenino , Células HEK293 , Humanos , Inmunización , Lipoproteínas/química , Lipoproteínas/inmunología , Enfermedad de Lyme/inmunología , Enfermedad de Lyme/microbiología , Ratones , Ratones Endogámicos BALB C , Proteína con Dominio Pirina 3 de la Familia NLR/agonistas , Proteína con Dominio Pirina 3 de la Familia NLR/inmunología , Células RAW 264.7RESUMEN
Pseudorabies virus (PrV), a causative agent of Aujeszky's disease, is deadly to most mammals with the exception of higher primates and men. This disease causes serious economic loses among farm animals, especially pigs, yet many European countries are today claimed to be Aujeszky's disease free because of the discovery of an efficient vaccination for pigs. In reality, the virus is still present in wild boar. Current vaccines are neither suitable for dogs nor are there anti-PrV drugs approved for veterinary use. Therefore, the disease still represents a high threat, particularly for expensive hunting dogs that can come into close contact with infected boars. Here we report on the anti-PrV activities of a series of synthetic diaminopurine-based acyclic nucleoside phosphonate (DAP-ANP) analogues. Initially, all synthetic DAP-ANPs under investigation are shown to exhibit minimal cytotoxicity by MTT and XTT tests (1-100µM range). Thereafter in vitro infection models are established using PrV virus SuHV-1, optimized on PK-15 and RK-13 cell lines. Out of the six DAP-ANP analogues tested, analogue VI functionalized with a cyclopropyl group on the 6-amino position of the purine ring proves the most effective antiviral DAP-ANP analogue against PrV infection, aided by sufficient hydrophobic character to enhance bioavailability to its cellular target viral DNA-polymerase. Four other DAP-ANP analogues with functional groups introduced to the C2'position are shown ineffective against PrV infection, even with favourable hydrophobic properties. Cidofovir(®), a drug approved against various herpesvirus infections, is found to exert only low activity against PrV in these same in vitro models.