Add Feed
Publication Archives
2007
Preparation and Characterization of Nickel Nanoparticles for Binding to His-tag Proteins and Antigens.
J Patel, R O'carra, J Jones, JG Woodward, and RJ Mumper.
Pharm Res. 2007 Feb;24(2):343-52. Epub 2006 Dec 19.
Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, Lexington, KY 40536-0082, USA.
PURPOSE: The purpose of these studies was to prepare nanoparticles (NPs) with a small amount of surface-chelated nickel for obtaining enhanced binding of histidine-tagged (his-tag) proteins compared to non-histidine-tagged protein binding to charged nanoparticles. MATERIALS AND METHODS: NPs were prepared from oil-in-water microemulsion precursors using emulsifying wax, 3 mM Brij 78 and 0.1 mM DOGS-NTA-Ni lipid (referred to as Ni-NPs). The amount of lipid entrapped in the NPs was quantitated by atomic emission spectroscopy (AES). The Ni-NPs were investigated for binding to two his-tag proteins, green fluorescent protein (GFP) and his-tag HIV-1 Gag p24. In vivo studies in mice were carried out to evaluate the immune responses obtained to his-tag Gag p24 bound to Ni-NPs. RESULTS: AES studies demonstrated that approximately 5% of the DOGS-NTA-Ni lipid used was entrapped in the NPs. The optimal binding ratio his-tag GFP and his-tag Gag p24 to Ni-NPs was found to be 1:33.7 and 1:35.4 w/w, respectively. This interaction was stable at 37 degrees C in PBS, pH 7.4 over 4 h and the interaction of his-tag GFP with the Ni-NPs was enhanced compared to control NPs prepared with no Ni on the surface (NTA-NPs). The in vivo studies demonstrated enhanced serum IgG and IgG2a responses to his-tag Gag p24 bound to Ni-NPs compared to protein adjuvanted with Alum or adsorbed on the surface of control NTA-NPs. CONCLUSIONS: Ni-NPs can be used to bind strongly to his-tag proteins. This system was demonstrated to have potential applications in vaccine delivery for enhancing immune responses to protein-based vaccines.
Publication Types:
    Research Support, N.I.H., Extramural
    Research Support, Non-U.S. Gov't
PMID: 17180725 [PubMed - indexed for MEDLINE]
Formulation and In-Vitro and In-Vivo Evaluation of a Mucoadhesive Gel Containing Freeze Dried Black Raspberries: Implications for Oral Cancer Chemoprevention
SR Mallery, GD Stoner, PE Larsen, HW Fields, KA Rodrigo, SJ Schwartz, Q Tian, J Dai and RJ Mumper.
Pharm. Res. (2007) 24:728-737.
Department of Oral Maxillofacial Surgery & Pathology, College of Dentistry, The Ohio State University, Columbus, OH 43210-1241, USA. mallery.1@osu.edu
PURPOSE: The purpose of these studies was to formulate mucoadhesive gels containing freeze dried black raspberries (FBR) and to determine optimum parameters for a subset of FBR bioactive compounds including anthocyanin stability, absorption and penetration in-vitro and in-vivo. MATERIALS AND METHODS: Berry gels were prepared having FBR at 5% and 10% w/w and final pHs ranging from 3.5 to 7.5. A HPLC assay was developed to quantify and determine the stability of the anthocyanins in the gels. A single time-point study was performed to determine anthocyanin uptake when the gels were applied to oral mucosa. Penetration of anthocyanins into human oral tissue explants was determined as a function of gel pH and FBR content. A HPLC-mass spectroscopy assay was utilized to quantify the anthocyanin levels in human oral tissue explants, saliva, and blood. RESULTS: The stability of anthocyanins in the gel was directly related to gel pH and storage temperature. Maximum stability of anthocyanins was found at lower pH (pH 3.5) and storage temperature (4 degrees C). Anthocyanins contained in mucoadhesive berry gel formulations were readily absorbed into human oral mucosa tissue as evidenced by detectable blood levels within 5 min after gel application. There was a trend for greater penetration of anthocyanins into tissue explants for berry gels with a final pH of 6.5 versus pH 3.5. CONCLUSIONS: Formulation and characterization of a novel gel formulation for local delivery of chemopreventive compounds to human oral mucosal tissues has been described. The results show anthocyanin stability was dependent upon gel pH and storage temperature and also demonstrate that the gel composition is well-suited for absorption and penetration into the target oral mucosal tissue site.
Publication Types:
Clinical Trial
Research Support, N.I.H., Extramural
Research Support, U.S. Gov't, Non-P.H.S.
PMID: 17372698 [PubMed - indexed for MEDLINE]
Copper Chelation by D-penicillamine Generates Reactive Oxygen Species that are Cytotoxic to Human Leukemia and Breast Cancer Cells
Gupte A, Mumper RJ. Free Radical Biology & Medicine. (2007) 43:1271-1278
Department of Pharmaceutical Sciences, College of Pharmacy, University of
Kentucky, Lexington, KY 40536-0082, USA.
Serum and tumor copper levels are significantly elevated in a variety of alignancies including breast, ovarian, gastric, lung, and leukemia. D-Penicillamine (D-pen), a copper-chelating agent, at low concentrations in the
presence of copper generates concentration-dependent cytotoxic hydrogen peroxide (H(2)O(2)). The purpose of these studies was to investigate the in vitro cytotoxicity, intracellular reactive oxygen species (ROS) generation, and the eduction in intracellular thiol levels due to H(2)O(2) and other ROS generated from copper-catalyzed D-pen oxidation in human breast cancer cells (BT474, MCF-7) and human leukemia cells (HL-60, HL-60/VCR, HL-60/ADR). D-pen (</=400 muM) in the resence of cupric sulfate (10 muM) resulted in concentration-dependent cytotoxicity. Catalase was able to completely protect the cells, substantiating
the involvement of H(2)O(2) in cancer cell cytotoxicity. A linear correlation between the D-pen concentration and the intracellular ROS generated was shown in both breast cancer and leukemia cells. D-pen in the presence of copper also resulted in a reduction in intracellular reduced thiol levels. The H(2)O(2)-mediated cytotoxicity was greater in leukemia cells compared to breast cancer cells. These results support the hypothesis that D-pen can be employed as a cytotoxic copper-chelating agent based on its ROS-generating ability.
PMID: 17893040 [PubMed - in process]
An Investigation into Copper Catalyzed D-Penicillamine Oxidation and Subsequent Hydrogen Peroxide Generation
A Gupte and RJ Mumper.
J. Inorganic Biochemistry. (2007) 101:594-602.
Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, 725 Rose Street, Lexington, KY 40536-0082, USA.
D-Penicillamine is a potent copper (Cu) chelating agent. D-Pen reduces Cu(II) to Cu(I) in the process of chelation while at the same time being oxidized to D-penicillamine disulfide. It has been proposed that hydrogen peroxide is generated during this process. However, definitive experimental proof that hydrogen peroxide is generated remains lacking. Thus, the major aims of these studies were to confirm and quantitatively assess the in vitro production of hydrogen peroxide during copper catalyzed D-penicillamine oxidation. The potential cytotoxic effect of hydrogen peroxide generation was also investigated in vitro against MCF-7 human breast cancer cells. Cell cytotoxicity resulting from the incubation of D-penicillamine with copper was compared to that of D-penicillamine, copper and hydrogen peroxide. The mechanism of copper catalyzed D-penicillamine oxidation and simultaneous hydrogen peroxide production was investigated as a function of time, concentration of cupric sulfate or ferric chloride, temperature, pH, anaerobic condition and chelators such as ethylenediaminetetraacetic acid and bathocuproinedisulfonic acid. A simple, sensitive and rapid HPLC assay was developed to simultaneously detect D-penicillamine, its major oxidation product D-penicillamine disulfide, and hydrogen peroxide in a single run. Hydrogen peroxide was shown to be generated in a concentration dependent manner as a result of D-penicillamine oxidation in the presence of cupric sulfate. Chelators such as ethylenediaminetetraacetic acid and
bathocuproinedisulfonic acid were able to inhibit D-penicillamine oxidation. The incubation of MCF-7 human breast cancer cells with D-penicillamine plus cupric sulfate resulted in the production of reactive oxygen species within the cell and cytotoxicity that was comparable to free hydrogen peroxide.
PMID: 17275091 [PubMed - indexed for MEDLINE]
Cationic Nanoparticles for Delivery of CpG Oligodeoxynucleotide and Ovalbumin: In Vitro and In Vivo Assessment
Patel, JD; Gandhapudi, S; Jones, J; O'Carra, R; Woodward, JG; Mumper, RJJournal of Biomedical Nanotechnology, Volume 3, Number 1, April 2007 , pp. 97-106(10)
Publisher: American Scientific Publishers
The use of cationic nanoparticles (NPs) for enhancing the delivery of an immunostimulatory adjuvant, CpG ODN, and model antigen, OVA to dendritic cells was investigated in these studies. In vitro studies demonstrated that NPs were taken up efficiently by bone-marrow derived dendritic cells (BMDDCs), with approximately 70% of the NPs found associated with cells over 12 hr. The presence of NPs intracellulary in DCs was confirmed by confocal microscopy. NPs alone did not cause release of IL-12 from BMDDCs; however, CpG-coated NPs (CpG/NPs) resulted in the release of IL-12 and the cytokine levels were greater using the NPs than CpG alone. Adoptive transfer experiments using OT-1 TCR transgenic T cells demonstrated higher proliferation of the OT-1 cells using OVA-coated NPs (OVA/NPs) compared to OVA alone, especially at lower doses of OVA. Taken together, the in vitro and in vivo data suggest that nanoparticles can enhance the uptake of antigen or immunostimulatory adjuvant into antigen presenting cells such as dendritic cells, and facilitate MHC class I restricted antigen presentation to CD8+ T cells. Moreover, in vivo immunization studies in BALB/c mice demonstrated that significant enhancements in humoral immune responses to OVA can be obtained using CpG-coated NPs compared to either CpG or NPs alone.
Document Type: Research article
DOI: 10.1166/jbn.2007.007
Nanotemplate-Engineered Nanoparticles Containing Gadolinium for Magnetic Resonance Imaging of Tumors
Zhu, D; Hardy, PA; Leggas, M; Jay, M
Invest Radiology, in press
This abstract is currently in press and is not yet available.
Aqueous polystyrene–fluor nanosuspensions for quantifying alpha and beta- radiation
Donghua Zhu and Michael Jay2007 Nanotechnology 18 225502 (6pp)
Department of Pharmaceutical Sciences, University of Kentucky, Lexington, KY 40536-0082, USA
Fluor-containing nanoparticle suspensions prepared from styrene-in-water microemulsions were used to quantify 14C in various sample matrices by aqueous liquid scintillation counting. These suspensions exhibited greater quench resistance than a conventional organic cocktail and were very efficient at detecting higher energy β- emitters and α itters. A polymerizable scintillant was prepared to prevent leaching of fluors. The relationship between particle size, kinetic energy of β- particles and counting efficiency was simulated by a theoretical model.
doi:10.1088/0957-4484/18/22/225502