Administration In Mouse Model Research Articles

Synthetic platelet (SynthoPlate) technology enhances hemostasis in both prophylactic and emergency administration in mouse models of bleeding

Synthetic platelet (SynthoPlate) technology enhances hemostasis in both prophylactic and emergency administration in mouse models of bleeding

A molecular patch for DMD

Antisense oligonucleotides rescue symptoms of Duchenne muscular dystrophy.

MicroRNAs in alcoholic liver disease.

Alcoholic liver disease (ALD) is characterized by hepatocyte damage, inflammatory cell activation and increased intestinal permeability leading to the clinical manifestations of alcoholic hepatitis. Selected members of the family of microRNAs are affected by alcohol, resulting in an abnormal miRNA profile in the liver and circulation in ALD. Increasing evidence suggests that mRNAs that regulate inflammation, lipid metabolism and promote cancer are affected by excessive alcohol administration in mouse models of ALD. This communication highlights recent findings in miRNA expression and functions as they relate to the pathogenesis of ALD. The cell-specific distribution of miRNAs, as well as the significance of circulating extracellular miRNAs, is discussed as potential biomarkers. Finally, the prospects of miRNA-based therapies are evaluated in ALD.

Systematic evaluation of antibody-mediated siRNA delivery using an industrial platform of THIOMAB-siRNA conjugates.

Delivery of siRNA is a key hurdle to realizing the therapeutic promise of RNAi. By targeting internalizing cell surface antigens, antibody–siRNA complexes provide a possible solution. However, initial reports of antibody–siRNA complexes relied on non-specific charged interactions and have not been broadly applicable. To assess and improve this delivery method, we built on an industrial platform of therapeutic antibodies called THIOMABs, engineered to enable precise covalent coupling of siRNAs. We report that such coupling generates monomeric antibody–siRNA conjugates (ARCs) that retain antibody and siRNA activities. To broadly assess this technology, we generated a battery of THIOMABs against seven targets that use multiple internalization routes, enabling systematic manipulation of multiple parameters that impact delivery. We identify ARCs that induce targeted silencing in vitro and extend tests to target prostate carcinoma cells following systemic administration in mouse models. However, optimal silencing was restricted to specific conditions and only observed using a subset of ARCs. Trafficking studies point to ARC entrapment in endocytic compartments as a limiting factor, independent of the route of antigen internalization. Our broad characterization of multiple parameters using therapeutic-grade conjugate technology provides a thorough assessment of this delivery technology, highlighting both examples of success as well as remaining challenges.

Effects of 2-methoxyestradiol administration in mouse models purported to show signs of preeclampsia and fetal growth restriction

Plasma concentration of 2-methoxyestradiol (2-ME) and placental expression of catechol-O-methyltransferase(COMT) are elevated in normal pregnancy, but reduced in women with preeclampsia (PE). Women with PE and fetal growth restriction (FGR)exhibit decreased utero-placental blood flow. Catechol-O-methyltransferase knockout mice (COMT -/- ) and female CBA/J mice mated with male DBA/2 mice (CBA/J × DBA/2)show many signs of PE during pregnancy and deliver growth-restricted pups. 2-ME is known to induce significant vasorelaxation of uterine arteries from pregnant mice. We hypothesized that 2-ME administration during pregnancy will lead to an increase in uterine artery blood flow velocity in COMT -/- and CBA/J × DBA/2 mice and therefore ameliorate PE-like signs and rescue fetal growth in these animal models. Pregnant COMT -/- and their controls (C57BL/6),and CBA/J × DBA/2 and their controls (CBA/J × BALB/c),were in- jected subcutaneously daily with 10 ng of 2-ME or vehicle (olive oil) from gestational day (GD) 12.5 to 17.5. There was no significant effect of genotype/strain or treatment on maternal blood pressure, uterine artery blood flow velocity or fetal growth. A perturbed phenotype only occurred in the COMT -/- mice in regard to umbilical artery flow veloc - ity, proteinuria and 2-ME levels. Administration of 2-ME led to normalization ofumbilical artery blood flow velocity and proteinuria in COMT -/- mice.

Abstract 5614: Legumain protease substrate modified TAT-liposome cargo: an efficient tool for targeting malignant diseases.

Abstract Tumor targeting specificity and efficacy of the internalization of macro-biomolecular drugs have emerged as two major obstacles hampering the application of liposome-based delivery system against tumor. Trans-activating transcriptional activator (TAT) is a member of the cell-penetrating peptides which enhance the penetration of various macro-biomolecular cargos. In this study, we developed a modified TAT-Liposome cargo in which the activation of TAT peptide was blocked by Legumain protease substrate Ala-Ala-Asn-(AAN). Firstly, we confirmed the extremely high level of Legumain expression in a variety of solid tumors, as well as its specific effect on recognition and digestion of AAN. Then we conjugated AAN with the TAT peptide and constructed the modified liposome (AAN-TAT-Lipo) cargo. Flow-cytometry assay showed the internalization of AAN-TAT-Lipo was significantly higher than that of AAN-Lipo in 4T1 cells which expressed active Legumain. In vivo, the concentration of Dox encapsulated in AAN-TAT-Lipo was significantly higher in the tumor sites and lower in normal tissues compared with Free-Dox, AAN-Lipo-Dox and TAT-Lipo-Dox groups after administration in mouse model of orthotopic breast cancer. Luciferase assay showed that the AAN-TAT-Lipo-Dox dramatically inhibited tumor growth compared with other groups. TUNEL staining demonstrated that the apoptotic cells in tumor sites were significantly increased in the group of AAN-TAT-Lipo-Dox, compared with other groups. Whereas, the apoptotic cells in the heart, liver, spleen and kidney were decreased in the group of AAN-TAT-Lipo-Dox. Taken together, the modified TAT-lipo cargo via blocking TAT peptide activation with a Legumain specific substrate, AAN, is proven effective for improving the efficacy of internalization, and reducing the systemic toxicity of the tumor targeting delivery system as well. Citation Format: Ze Liu, Min Xiong, Debbie Liao, Dan Lv, Ralph A. Reisfeld, Wolfgang Wrasidlo, Si Chen, Dwayne G. Stupack, Peiqing Sun, Xiaoyue Tan, Rong Xiang. Legumain protease substrate modified TAT-liposome cargo: an efficient tool for targeting malignant diseases. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 5614. doi:10.1158/1538-7445.AM2013-5614

Expression of verocytotoxicEscherichia coliantigens in tobacco seeds and evaluation of gut immunity after oral administration in mouse model

Verocytotoxic Escherichia (E.) coli strains are responsible for swine oedema disease, which is an enterotoxaemia that causes economic losses in the pig industry. The production of a vaccine for oral administration in transgenic seeds could be an efficient system to stimulate local immunity. This study was conducted to transform tobacco plants for the seed-specific expression of antigenic proteins from a porcine verocytotoxic E. coli strain. Parameters related to an immunological response and possible adverse effects on the oral administration of obtained tobacco seeds were evaluated in a mouse model. Tobacco was transformed via Agrobacteium tumefaciens with chimeric constructs containing structural parts of the major subunit FedA of the F18 adhesive fimbriae and VT2e B-subunit genes under control of a seed specific GLOB promoter. We showed that the foreign Vt2e-B and F18 genes were stably accumulated in storage tissue by the immunostaining method. In addition, Balb-C mice receiving transgenic tobacco seeds via the oral route showed a significant increase in IgA-positive plasma cell presence in tunica propria when compared to the control group with no observed adverse effects. Our findings encourage future studies focusing on swine for evaluation of the protective effects of transformed tobacco seeds against E. coli infection.

Efficacy and Toxicological Studies of Cremophor EL Free Alternative Paclitaxel Formulation

In the present study, Cremophor EL free paclitaxel elastic liposomal formulation consisting of soya phosphatidylcholine and biosurfactant sodium deoxycholate was developed and optimized. The toxicological profile, antitumor efficacy and hemolytic toxicity of paclitaxel elastic liposomal formulation in comparison to Cremophor EL based marketed formulation were evaluated. Paclitaxel elastic liposomal formulations were prepared and characterized in vitro, ex-vivo and in vivo. Single dose toxicity study of paclitaxel elastic liposomal and marketed formulation was carried out in dose range of 10, 20, 40, 80, 120, 160 and 200 mg/kg. Cytotoxicity of developed formulation was evaluated using small cell lung cancer cell line (A549). Antitumor activity of developed formulation was compared with the marketed formulation using Cytoselect™ 96-well cell transformation assay. In vivo administration of paclitaxel elastic liposomal formulation into mice showed 6 fold increase in Maximum Tolerated Dose (MTD) in comparison to the marketed formulation. Similarly, LD50 (141.6 mg/kg) was also found to increase significantly than the marketed formulation (16.7 mg/kg). Result of antitumor assay revealed a high reduction of tumor density with paclitaxel elastic liposomal formulation. Reduction in hemolytic toxicity was also observed with paclitaxel elastic liposomal formulation in comparison to the marketed formulation. The carrier based approach for paclitaxel delivery demonstrated significant reduction in toxicity as compared to the Cremophor EL based marketed formulation following intra-peritoneal administration in mice model. The reduced toxicity and enhanced anti-cancer activity of elastic liposomal formulation strongly indicate its potential for safe and effective delivery of paclitaxel.

Interleukin‐21 activates human natural killer cells and modulates their surface receptor expression

Interleukin (IL)-21 is a novel cytokine that has been shown to enhance proliferation and activation of CD8+ T cells, enhance natural killer (NK) cell activity and costimulate anti-CD40-driven B-cell proliferation in mice. Several studies have furthermore demonstrated antitumour effects of IL-21 administration in mouse models. In this study we have investigated how IL-21 affects the survival and cytotoxicity of human NK cells and modulates their expression of surface receptors and of the effector molecules granzyme B and perforin. In contrast to murine NK cells, where IL-21 alone cannot sustain survival, IL-21 and IL-2 were equally efficient in sustaining survival of human NK cells. In the absence of other cytokines, IL-21 had little effect on expression of a panel of surface receptors on human NK cells. However, IL-21 synergized with IL-2 to up-regulate several surface receptors, including NKG2A, CD25, CD86 and CD69. The CD25+ CD86+ NK cells were CD56(bright) and were large and granular. Expression of the effector molecules perforin and granzyme A and B was up-regulated by IL-21 at both mRNA and protein levels. Furthermore, IL-21 increased the cytotoxicity of NK cells against K562 target cells. These findings suggest that IL-21 modulates NK cell activity through induction of intracellular effector molecules as well as modulation of surface receptor expression.

Safety of intracerebroventricular copper histidine in adult rats

Classical Menkes disease is an X-linked recessive neurodegenerative disorder caused by mutations in a P-type ATPase (ATP7A) that normally delivers copper to the developing central nervous system. Infants with large deletions, or other mutations in ATP7A that incapacitate copper transport to the brain, show poor clinical outcomes and subnormal brain copper despite early subcutaneous copper histidine (CuHis) injections. These findings suggest a need for direct central nervous system approaches in such patients. To begin to evaluate an aggressive but potentially useful new strategy for metabolic improvement of this disorder, we studied the acute and chronic effects of CuHis administered by intracerebroventricular (ICV) injection in healthy adult rats. Magnetic resonance imaging (MRI) after ICV CuHis showed diffuse T 1-signal enhancement, indicating wide brain distribution of copper after ICV administration, and implying the utility of this paramagnetic metal as a MRI contrast agent. The maximum tolerated dose (MTD) of CuHis, defined as the highest dose that did not induce overt toxicity, growth retardation, or reduce lifespan, was 0.5 mcg. Animals receiving multiple infusions of this MTD showed increased brain copper concentrations, but no significant differences in activity, behavior, and somatic growth, or brain histology compared to saline-injected controls. Based on estimates of the brain copper deficit in Menkes disease patients, CuHis doses 10-fold lower than the MTD found in this study may restore proper brain copper concentration. Our results suggest that ICV CuHis administration have potential as a novel treatment approach in Menkes disease infants with severe mutations. Future trials of direct CNS copper administration in mouse models of Menkes disease will be informative.

Antinociceptive effects of supraspinal rat cart (55–102) peptide in mice

We investigated the effects of rat cocaine- and amphetamine-regulated transcript CART (55–102) after i.c.v. administration in mouse models of acute and persistent pain. CART was not active in the tail-flick or PPQ tests. It increased the latency to paw licking in the hot-plate test but only at doses that impaired motor function. CART produces antinociception in the formalin test in both phases. Our results suggest that CART is involved in supraspinal pain transmission.