Macrophage repolarization with targeted alginate nanoparticles containing IL-10 plasmid DNA for the treatment of experimental arthritis.

In this study, we have shown for the first time the effectiveness of a non-viral gene transfection strategy to re-polarize macrophages from M1 to M2 functional sub-type for the treatment of rheumatoid arthritis (RA). An anti-inflammatory (IL-10) cytokine encoding plasmid DNA was successfully encapsulated into non-condensing alginate based nanoparticles and the surface of the nano-carriers was modified with tuftsin peptide to achieve active macrophage targeting. Enhanced localization of tuftsin-modified alginate nanoparticles was observed in the inflamed paws of arthritic rats upon intraperitoneal administration. Importantly, targeted nanoparticle treatment was successful in reprogramming macrophage phenotype balance as ∼66% of total synovial macrophages from arthritic rats treated with the IL-10 plasmid DNA loaded tuftsin/alginate nanoparticles were in the M2 state compared to ∼9% of macrophages in the M2 state from untreated arthritic rats. Treatment significantly reduced systemic and joint tissue pro-inflammatory cytokines (TNF-α, IL-1ß, and IL-6) expression and prevented the progression of inflammation and joint damage as revealed by magnetic resonance imaging and histology. Treatment enabled animals to retain their mobility throughout the course of study, whereas untreated animals suffered from impaired mobility. Overall, this study demonstrates that targeted alginate nanoparticles loaded with IL-10 plasmid DNA can efficiently re-polarize macrophages from an M1 to an M2 state, offering a novel treatment paradigm for treatment of chronic inflammatory diseases.

Multifunctional nanoparticles for targeting cancer and inflammatory diseases.

The interplay between cancer and inflammation has been well documented over the years and the role of nanomedical technologies for treating both these diseases has become evident over the past few decades. With the advances in nanoparticle-based imaging and therapeutic platforms that can exploit the pathological conditions of the tumor and the inflamed sites to effectively deliver drugs, genes and imaging/contrast agents; the management of such conditions with favorable therapeutic outcomes seems plausible. This review will summarize some of the latest advances in the field of targeted nanomedicine development to combat cancer and inflammation. Illustrative examples of multifunctional-targeted nanosystems are presented that highlight their potential in delivering diverse payloads, including small molecule drugs, nucleic acids and imaging agents for simultaneous theranostic interventions.

Nano-sized calcium phosphate particles for periodontal gene therapy.

BACKGROUND: Growth factors such as platelet-derived growth factor (PDGF) have significantly enhanced periodontal therapy outcomes with a high degree of variability, mostly due to the lack of continual supply for a required period of time. One method to overcome this barrier is gene therapy. The aim of this in vitro study is to evaluate PDGF-B gene delivery in fibroblasts using nano-sized calcium phosphate particles (NCaPP) as vectors. METHODS: NCaPP incorporating green fluorescent protein (NCaPP-GFP) and PDGF-B (NCaPP-PDGF-B) plasmids were synthesized using an established precipitation system and characterized using transmission electron microscopy and 1.2% agarose gel electrophoresis. Biocompatibility and transfection of the nanoplexes in fibroblasts were evaluated using cytotoxicity assay and florescence microscopy, respectively. Polymerase chain reaction and enzyme-linked immunosorbent assay were performed to evaluate PDGF-B transfection after different time points of treatments, and the functionality of PDGF-B transfection was evaluated using the cell proliferation assay. RESULTS: Synthesized NCaPP nanoplexes incorporating the genes of GFP and PDGF-B were spherical in shape and measured about 30 to 50 nm in diameter. Gel electrophoresis confirmed DNA incorporation and stability within the nanoplexes, and 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium reagent assay demonstrated their biocompatibility in fibroblasts. In vitro transfection studies revealed a higher and longer lasting transfection after NCaPP-PDGF-B treatment, which lasted up to 96 hours. Significantly enhanced fibroblast proliferation observed in NCaPP-PDGF-B-treated cells confirmed the functionality of these nanoplexes. CONCLUSION: NCaPP demonstrated higher levels of biocompatibility and efficiently transfected PDGF plasmids into fibroblasts under described in vitro conditions.

Tuftsin-modified alginate nanoparticles as a noncondensing macrophage-targeted DNA delivery system.

The main objective of this study was to evaluate macrophage-targeted alginate nanoparticles as a noncondensing gene delivery system for potential anti-inflammatory therapy. An external gelation method was employed to form plasmid DNA-encapsulated alginate nanoparticles. The nanoparticle surface was modified with a peptide sequence containing tuftsin (TKPR), and transfection efficiency was determined in J774A.1 macrophages. The effect of transfected mIL-10 in blocking expression of tumor necrosis factor-alpha (TNF-α) was evaluated in lipopolysaccharide (LPS)-stimulated cells. Scrambled peptide- and tuftsin-modified cross-linked alginate nanoparticles efficiently encapsulated plasmid DNA and protected against DNase I degradation. The transgene expression efficiencies, measured using GFP and mIL-10 expressing plasmid DNA, were highest with tuftsin-modified nanoparticles. Levels of TNF-α were significantly lower (p < 0.0001) in LPS-stimulated cells that were transfected with mIL-10 using alginate nanoparticles. The results of the study show that noncondensing alginate nanoparticles can efficiently deliver plasmid DNA, leading to sustained in vitro gene expression in macrophages.