Disclosed herein are novel compounds, pharmaceutical compositions comprising such compounds and related methods of their use. The compounds described herein are useful, e.g. as liposomal delivery vehicles to facilitate the delivery of encapsulated polynucleotides to target cells and subsequent transfection of said target cells, and in certain embodiments are characterized as having one or more properties that afford such compounds advantages relative to other similarly classified lipids.

The present disclosure relates to arginase albumin binding domain (ABD) fusion proteins and methods of preparation and use thereof. Also provided are methods involving arginine depletion for the treatment of obesity, metabolic disorders, and related complications and comorbidities.

In one embodiment, a single modality cancer immunotherapy regimen that includes a therapeutic composition is provided. Such a therapeutic composition may include a Salmonella strain comprising a plasmid that expresses an shRNA molecule that suppresses the expression of an immunosuppressive target and suppresses tumor growth. In some aspects, the Salmonella strain is an attenuated Salmonella typhimurium strain. In other aspects, the immunosuppressive target is STAT3, IDO1, IDO2, Arginase 1, iNOS, CTLA-4, TGF-, IL-10, pGE2 or VEGF. In one embodiment, the immunosuppressive target is IDO1 or Arg1 and the shRNA molecule is any one of SEQ ID NO:5-14.

In one embodiment, a single modality cancer immunotherapy regimen that includes a therapeutic composition is provided. Such a therapeutic composition may include a Salmonella strain comprising a plasmid that expresses an shRNA molecule that suppresses the expression of an immunosuppressive target and suppresses tumor growth. In some aspects, the Salmonella strain is an attenuated Salmonella typhimurium strain. In other aspects, the immunosuppressive target is STAT3, IDO1, IDO2, Arginase 1, iNOS, CTLA-4, TGF-, IL-10, pGE2 or VEGF. In one embodiment, the immunosuppressive target is IDO1 or Arg1 and the shRNA molecule is any one of SEQ ID NO:5-14.

Methods and compositions comprising recombinant Arginase I proteins which are capable of depleting the plasma arginine levels in a subject are disclosed. The methods and compositions can be used to modulate the activity of the immune system in a subject. Modulation of the immune system is useful in the treatment of immune disorders and in preventing rejection of a transplanted organ, tissue, or cell. The methods and compositions can also be used to treat a bone condition of a subject.

The present invention relates to the provision of genetically modified microbial cells, such as yeast cells with an improved ability for producing L-ornithine and its derivatives. Overproduction of L-ornithine is obtained in the first place by the down-regulation or attenuation of specially selected genes, wherein said genes encode enzymes involved in the L-ornithine consumption and/or degradation pathways. Further L-ornithine production ability is improved by down-regulation, attenuation, deletion or overexpression of specially selected genes, wherein said genes encode enzymes and/or proteins involved in the L-ornithine acetylated derivatives cycle, L-glutamate synthesis pathways, subcellular trafficking, TCA cycle, pyruvate carboxylation pathway, respiratory electron-transport chain, and the carbon substrates' assimilation machinery. The invention additionally provides a method to produce L-ornithine with said modified eukaryotic cells.

Disclosed herein are novel compounds, pharmaceutical compositions comprising such compounds and related methods of their use. The compounds described herein are useful, e.g., as liposomal delivery vehicles to facilitate the delivery of encapsulated polynucleotides to target cells and subsequent transfection of said target cells, and in certain embodiments are characterized as having one or more properties that afford such compounds advantages relative to other similarly classified lipids.

Pathological retinal neovascularization is a common micro-vascular complication in several retinal diseases including retinopathy of prematurity (ROP), diabetic retinopathy, age related macular degeneration and central vein occlusion. Disclosed herein are compositions and methods useful for the treatment or prevention of retinal neovascularization and related diseases in a subject in need thereof. Exemplary methods include administering a composition including PEGylated arginase 1 to a subject in need thereof to promote reparative angiogenesis and decrease retinal neovascularization in the eye.

Compositions and methods for the preparation of high purity arginase and high efficiency preparation of monosubstituted polyethylene glycol conjugation of arginase are provided, as are methods for using arginase in combination with asparaginase to inhibit cancer cells. High purity arginase is provided by applying an initial high temperature precipitation step, followed by ion exchange to provide arginase at a purity of 90% or greater. Conjugation with either linear or branched polyethylene glycol is performed using a maleimide-derivatized polyethylene glycol at low molar excess relative to arginase and at reduced temperature. Such polyethylene glycol-derivatized arginase is useful in combination with asparaginase in inhibiting the growth of cancer cells, particularly cells that have low endogenous asparaginase expression.

Described are methods for producing recombinant Arginase, such as PEGylated, cobalt-substituted recombinant human Arginase 1. Also described are pharmaceutical compositions comprising such recombinant Arginase, as well as methods of treatment and uses of such recombinant Arginase.