ABSTRACT
PURPOSE: The purpose of this work is to demonstrate the feasibility of using a proprietary technology called MicroCor™, based on solid-state, biodegradable microstructures (SSBMS), for transdermal delivery of macromolecules. METHODS: The proteins FITC-BSA (66 kDa) and recombinant protective antigen (rPA; 83 kDa) were incorporated into SSBMS arrays using a mold-based, liquid formulation casting and drying process. Arrays were applied to the skin with a custom applicator and then inspected to assess the extent of microstructure dissolution. In vitro FITC-BSA delivery to human cadaver skin was visualized using light and fluorescence microscopy and quantified by extracting and measuring the fluorescently labeled protein. rPA-containing SSBMS arrays were applied in vivo to Sprague-Dawley rats. The resulting serum IgG response was measured by ELISA and compared with responses elicited from intramuscular (IM) and intradermal (ID) routes of administration. RESULTS: FITC-BSA and rPA SSBMS arrays successfully penetrated the skin. Microstructure dissolution was observed over >95% of the array area and >75% of the microstructure length. FITC-BSA delivery correlated with protein content in the formulations. Antibody titers after transdermal delivery of rPA were comparable or higher than IM and ID titers. CONCLUSIONS: Transdermal delivery of macromolecules can be conveniently and effectively accomplished using the MicroCor technology.
Subject(s)
Antigens, Bacterial/administration & dosage , Biocompatible Materials/chemistry , Drug Delivery Systems/methods , Fluorescein-5-isothiocyanate/analogs & derivatives , Microinjections/instrumentation , Recombinant Proteins/administration & dosage , Serum Albumin, Bovine/administration & dosage , Administration, Topical , Animals , Drug Carriers/chemistry , Drug Delivery Systems/instrumentation , Enzyme-Linked Immunosorbent Assay , Equipment Design , Feasibility Studies , Female , Fluorescein-5-isothiocyanate/administration & dosage , Humans , Immunization/instrumentation , Immunization/methods , Immunoglobulin G/blood , Immunoglobulin G/immunology , In Vitro Techniques , Injections, Intradermal , Injections, Intramuscular , Microinjections/methods , Phase Transition , Rats , Rats, Sprague-Dawley , Skin/drug effects , Skin/metabolism , Technology, Pharmaceutical/methodsABSTRACT
The adsorption of four proteins, RNase A, HEWL, BSA, and beta-Lac, was examined on the surface of a negatively charged SiO(2)/TiO(2) optical waveguide. The amount of adsorbed protein followed the salt series Mg(2+)>Li(+)>Na(+)>K(+) and for anions Cl(-)>Br(-)>I(-). This ordering was attributed to protein adsorption being primarily influenced by changes in hydrophobic interactions between the surface and the protein resulting from differences in water structure arising from the presence of electrolytes.
Subject(s)
Electrolytes/chemistry , Proteins/metabolism , Water/chemistry , Adsorption/drug effects , Animals , Anions/chemistry , Buffers , Cations/chemistry , Cattle , Chickens , Hydrogen-Ion Concentration/drug effects , Hydrophobic and Hydrophilic Interactions , Lactoglobulins/metabolism , Models, Chemical , Muramidase/metabolism , Ribonuclease, Pancreatic/metabolism , Serum Albumin, Bovine/metabolism , Sodium Chloride/pharmacology , Solutions , Surface Properties/drug effectsABSTRACT
The objective of this work was to conduct an in vivo comparison of nanoparticles and microparticles as vaccine delivery systems. Poly (lactide-co-glycolide) (PLG) polymers were used to create nanoparticles size 110 nm and microparticles of size 800-900 nm. Protein antigens were then adsorbed to these particles. The efficacy of these delivery systems was tested with two protein antigens. A recombinant antigen from Neisseria meningitides type B (MenB) was administered intramuscularly (i.m.) or intraperitonealy (i.p.). An antigen from HIV-1, env glycoprotein gp140 was administered intranasally (i.n.) followed by an i.m. boost. From three studies, there were no differences between the nanoparticles and micro-particles formulations. Both particles led to comparable immune responses in mice. The immune responses for MenB (serum bactericidal activity and antibody titers) were equivalent to the control of aluminum hydroxide. For the gp140, the LTK63 was necessary for high titers. Both nanoparticles and microparticles are promising delivery systems.
Subject(s)
Drug Delivery Systems , Lactic Acid/chemistry , Nanoparticles/administration & dosage , Polyglycolic Acid/chemistry , env Gene Products, Human Immunodeficiency Virus/administration & dosage , Adjuvants, Immunologic/chemistry , Animals , Anions/administration & dosage , Antigens, Bacterial/administration & dosage , Antigens, Bacterial/metabolism , Chemistry, Pharmaceutical , Lactic Acid/administration & dosage , Mice , Microspheres , Neisseria meningitidis, Serogroup B/chemistry , Neisseria meningitidis, Serogroup B/immunology , Polyglycolic Acid/administration & dosage , Polylactic Acid-Polyglycolic Acid Copolymer , env Gene Products, Human Immunodeficiency Virus/chemistry , env Gene Products, Human Immunodeficiency Virus/immunologyABSTRACT
The objective of this work was to obtain a nanoparticle formulation that could be sterile filtered, lyophilized, and resuspended to the initial size with excipients appropriate for use as a vaccine formulation. Poly(lactide-co-glycolide) (PLG) polymers were used to create nanoparticles ranging in size from 110 to 230 nm. Protein antigens were adsorbed to the particles; the protein-nanoparticles were then lyophilized with the excipients. Vaccine compatible excipient combinations of sugars alone, surfactants alone, and sugars and surfactants were tested to find conditions where initial particle size was recovered. Sterile filtration of smaller nanoparticles led to minimal PLG losses and allowed the particle preparation to be a nonaseptic process. We found that the smaller nanoparticles of size approximately 120 nm required higher surfactant concentration to resuspend postlyophilization than slightly larger ( approximately 220 nm) particles. To resuspend 120 nm nanoparticles formulations of poly(vinyl alcohol) (PVA) with sucrose/mannitol or dioctyl sodium sulfosuccinate (DSS) with trehalose/mannitol were sufficient. The protein-nanoparticles resuspension with the same excipients was dependent on the protein and protein loading level. The nanoparticle formulations in vivo were either similar or had enhanced immunogenicity compared to aluminum hydroxide formulations. A lyophilized nanoparticle formulation with adsorbed protein antigen and minimal excipients is an effective vaccine delivery system.
Subject(s)
Drug Delivery Systems , Meningococcal Vaccines/administration & dosage , Nanoparticles/administration & dosage , Nanoparticles/chemistry , Animals , Bacterial Proteins/chemistry , Chemistry, Pharmaceutical , Drug Combinations , Excipients/chemistry , Female , Filtration , Freeze Drying , Immunoglobulin G/blood , Isatin/analogs & derivatives , Isatin/chemistry , Mannitol/chemistry , Mice , Mice, Inbred Strains , Ovalbumin/chemistry , Polyglactin 910/chemistry , Polyvinyl Alcohol/chemistry , Pyridines/chemistry , Serum Albumin, Bovine/chemistry , Succinates/chemistry , Surface-Active Agents/chemistry , Trehalose/chemistryABSTRACT
Sugar excipients are shown to reduce the adsorption of ribonuclease A, bovine serum albumin, and hen egg white lysozyme at the liquid-solid interface. The amount of protein adsorbed decreased as the concentration of the sugar increased. At the same sugar concentration, the ability of sugars to reduce protein adsorption followed the trend: trisaccharides > disaccharides > 6-carbon polyols > monosaccharides. This trend in adsorbed protein amounts among sugars was explained by stabilization of the protein native state in solution by the sugar excipients. The heat of solution of the amorphous saccharide was found to correlate with the amount of protein adsorbed.
