The University of Texas System

Swr&d Inc.

Jim Klostergaard

Gabriel Lopez-Berestein

Mien-Chie Hung

William A Yuill

Charles E Seeney

Donald D Gibson

Mathoor Sivaramakrishnan

Toshihiko Utsumi

Jim Turpin

Stanley D Tucker

Magnetically responsive therapeutic carriers comprise nanoparticles including single-domain nanoparticles comprising magnetite and having an average particle size ranging between 1 and 50 nanometers, clusters of the single-domain nanoparticles, the clusters having an average cluster size ranging between 5 and 1000 nanometers, and mixtures of the two. The single-domain nanoparticles are encapsulated with a silica coating. A silane coupling agent is bonded to the silica coating and has a specific pendant functional group capable of selectively binding with the therapeutic. Preferably, the bond between the specific pendant functional group and the therapeutic is a covalent bond. The movement of magnetically responsive nanoparticle therapeutic constructs, with concentration and extravasation/endocytosis at a target site, such as cancerous tumors, uses a controllable magnetic field generator adapted to move the therapeutic constructs in three dimensions, and is enhanced using a repetitively-varying magnetic field. A method for treating cancer comprises administering and magnetically guiding a therapeutic construct comprising paclitaxel.

Magnetically responsive nanoparticle therapeutic constructs and methods of making and using

A tumor necrosis factor (TNF) preparation with high cytolytic activity is described. The TNF preparation includes modified forms of TNF associated with or encapsulated within liposomes. The TNF molecule is modified at up to 3 amino acid residues per trimer with nearly complete retention (80-95%) of biological activity. Amino acid residues of the TNF are modified to include long chain fatty acids via TNF lysyl side chains and/or N-terminal amino acid groups. The disclosed modified TNF molecules provide a highly efficient method for preparing liposome-associated or encapsulated TNF complexes in either standard multilamellar vesicles (MLVs) or small unilamellar vesicles (SUVs) having enhanced in vivo stability. The liposomes of the present invention feature particularly small diameters in the range of 0.02-0.05 um in diameter. The binding of the modified TNF molecules to the surface of SUVs is up to 100% efficiency. Pharmacologically acceptable preparations of modified TNF for the particular treatment of TNF-responsive tumors are also provided. Methods of preparing liposomal-lipophilic TNF molecules are provided. Highly efficient methods of preparing stable, surface-associated protein liposome complexes having enhanced stability in vivo are also provided.

Preparation and characterization of liposomal formulations of tumor

Disclosed herein is a novel antitumor factor, termed Human Monocyte Toxin, obtained by the precise activation of cells of monocyte/macrophage lineage. Monocytes are isolated in the absence of endotoxin by counterflow elutriation. HMT release can be triggered by exposure to low levels of 6-0-stearoyl muramyl dipeptide, lipopolysaccharide, phorbol myristate acetate or other known macrophage activating agents. Triggering results in the rapid release of HMT which requires transcription, translation, and intact secretory apparatus. The requirement for precise control of the triggering agent concentration is disclosed.

Method for obtaining soluble antitumor factor

This invention provides a cytotoxin composition that inhibits mitochondrial respiration and causes cytostasis in cells, independent of nitric oxide. The invention comprises a conditioned supernatant derived from macrophage cell line (EA13.5) that inhibits mitochondrial respiration and causes cytostasis in cells. More particularly, the invention comprises a macrophage cytotoxin obtained from conditioned supernatant collected from cultured EA13.5 cell. This macrophage cytotoxin (1) inhibits mitochondrial respiration, (2) causes cytostasis independent of L-arginine derived nitric oxide, (3) is a weakly acidic (pI of about 7.5 to 8.0) glycoprotein (as determined by binding to lentil lectin sepharose). The invention also discloses a method for producing an L-arginine-derived nitric oxide-independent macrophage cytotoxin by culturing EA13.5 cells, adding IFN-.gamma. and lipopolysaccharide to trigger secretion of the macrophage cytotoxin into the conditioned supernatant, collecting the conditioned supernatant, and isolating the macrophage cytotoxin from the conditioned supernatant. Further disclosed by this invention is a method for producing a nitric oxide independent macrophage cytotoxin, that inhibits mitochondrial respiration independent of L-arginine, from cultured rodent macrophages.

Macrophage cytotoxin compositions and methods of preparation

A substantially purified preparation containing one or more soluble Iron-Releasing Monokines and a method of preparing and using same are disclosed. The monokine is heat labile and is retained by ultrafiltration on a YM-10 membrane. Molecular exclusion chromatography of macrophage conditioned supernatant containing the monokine yields fractions in the 30,000 to 65,000 relative molecular weight range with iron-releasing activity. Kinetic studies show that the monokine is rapidly released from activated macrophages after triggering with bacterial endotoxin, reaching plateau levels within 2-4 hours. The response of cells to the monokine depends on both the dose of the monokine administered and the duration of its exposure. The Iron-Releasing Monokine is distinct from other factors secreted by activated macrophages, such as a cytolytic factor and Respiratory Inhibition Factor which causes reversible lesions in the electron transport chain.

Growing community of inventors

Kingwood, TX, United States of America

Jim Klostergaard