How to optimize in vivo gene transfer to cardiac myocytes: mechanical or pharmacological procedures?

An efficient gene delivery system is a prerequisite for myocardial gene therapy. Among the various procedures studied so far, catheter-based percutaneous gene delivery to the myocardium through the coronary vessels seems the most relevant to routine clinical practice; however, the optimal conditions remain to be determined. We selectively infused adenoviral vectors encoding luciferase (1 x 10(9) PFU) or beta-galactosidase (1 x 10(10) PFU) into coronary arteries of adult rabbits in various experimental conditions. Coronary artery occlusion for 30 sec, during and after adenovirus delivery, was required to observe luciferase activity in the target area of the circumflex artery (4.0 +/- 1.0 x 10(5) vs. 1.1 +/- 0.2 x 10(4) RLU/mg with and without coronary occlusion, respectively, p < 0.01, and 1.0 +/- 0.1 x 10(3) RLU/mg using nonselective infusion). When adenoviruses were delivered using high-pressure infusion (82 +/- 12 vs. 415 +/- 25 mmHg before and during infusion, respectively, p < 0.01), luciferase activity increased to 8.5 +/- 2.5 x 10(5) RLU/mg (p < 0.05 vs coronary occlusion alone). Coronary venous sinus occlusion with saline buffer retroinfusion starting before and during anterograde adenovirus delivery resulted in a further 4.7-fold increase in luciferase activity (4.4 +/- 0.8 x 10(6) RLU/mg, p < 0.01) with 5-25% blue-stained myocytes in the target area, compared with 0-5% with the other procedures. Histamine or VEGF-A(165) pretreatment, used to increase vascular permeability, slightly increased gene transfer efficiency (8.5 +/- 2.0 x 10(5) and 9.0 +/- 2.5 x 10(5) RLU/mg respectively, p < 0.05 vs. coronary occlusion alone). We conclude that catheter-mediated adenoviral gene transfer to cardiac myocytes through coronary vessels can be a very efficient procedure for myocardial gene therapy, particularly when the vector residence time and perfusion pressure in the vessels are increased.     

Information transfer between health structures. How and to whom is the information transferred?

The evolution of the French health-care system is based on the development of patient management in the health-care system. The public services associate nurses with alternatives to hospitalization in order to favor the emergence of such facilities. This evolution changes the habits and the needs of professionals. Communication between the nurses is the basis of this function. In order to assure the continuity of health-care, both private and hospital nurses need information. However this is either not the case, or is inadequate to the expectations and needs of the nurses. The motives will be analyzed and some proposals offered. In recording and analyzing liaison records, interesting accounts were revealed which foresees the possibilities of an evolution at the information network level between the hospital and the extra-hospital sector. Some propositions will be put forth in order to assure a greater coherence in the endeavor for health-care continuity.     

Augmentation of pulmonary host defense against Pseudomonas by FcγRIIA cDNA transfer to the respiratory epithelium

Fcgamma receptors on the surface of phagocytic cells bind the Fc region of IgG and mediate binding, phagocytosis, and destruction of particulate antigens opsonized by the antigen-specific IgG molecule. The present study evaluates the feasibility of converting lung epithelial cells into phagocytic cells using adenovirus (Ad) vector-mediated gene transfer of FcgammaRIIA cDNA to induce expression of the human FcgammaRIIA receptor. Binding and phagocytosis of opsonized sheep red blood cells (SRBCs) by the A549 human lung epithelial cell line after Ad-mediated FcgammaRIIA gene transfer was demonstrated using light and fluorescence microscopy and phagocytic assays with (51)Cr-labeled SRBCs. When A549 cells were infected with an Ad vector expressing a FcgammaRIIA mutant in which 2 of 3 cytoplasmic tyrosines have been replaced with phenylalanine, only binding, but not phagocytosis, of opsonized SRBCs was observed. In vivo expression of FcgammaRIIA in the lung after intratracheal administration of the AdFcgammaRIIA enhanced clearance of opsonized Pseudomonas aeruginosa from the lung in normal rats and in mice deficient in Fcgamma receptor expression. Similar results were observed with a chimeric FcgammaRIIA construct containing the extracellular domain of FcgammaRIIIA. Together, these data demonstrate that Ad-mediated FcgammaRIIA receptor cDNA expression can mediate the binding and phagocytosis of opsonized particulate antigens by normally nonphagocytic cells, suggesting that gene-transfer strategies might be used to utilize nonphagocytic cells to clear bacteria or other opsonized particulate antigens from the respiratory tract.     

Microsomal transfer protein (MTP) inhibition—a novel approach to the treatment of homozygous hypercholesterolemia

Abstract

Homozygous familial hypercholesterolemia (HoFH) represents the most severe lipoprotein disorder, generally attributable to mutation(s) of the low-density lipoprotein receptor (LDL-R), i.e. autosomal dominant hypercholesterolemia type 1 (ADH1). Much lower percentages are due to alterations of apolipoprotein B (ADH2), or gain-of-function mutations of proprotein convertase subtilisin/kexin type 9 (PCSK9) (ADH3). In certain geographical areas a significant number of patients may be affected by an autosomal recessive hypercholesterolemia (ARH). Mutations may be also combined (two mutations of the same gene, compound heterozygosity), or two in different genes (double heterozygosity). Among the most innovative therapeutic approaches made available recently, inhibitors of the microsomal transfer protein (MTP) system have shown a high clinical potential. MTP plays a critical role in the assembly/secretion of very-low-density lipoproteins (VLDL), and its absence leads to apo B deficiency. MTP antagonists dramatically lower LDL-cholesterol (LDL-C) in animals, although a reported increase of liver fat delayed their clinical development. Lomitapide, the best-studied MTP inhibitor, reduces LDL-C by 50% or more in HoFH patients, with modest, reversible, liver steatosis. Recent US approval has confirmed an acceptable tolerability, provided patients adhere to a strictly low-fat regimen. There are no clinical data on atherosclerosis reduction/regression, but animal models provide encouraging results.     

Nonviral gene transfer with Mposome and protein

The development of improved gene transfermethods is a prerequisite for gene therapy to realizeits full potentials. One approach is the design ofplasmid-based delivery system that also termed "self-assembling complexes" such as cationic liposome-DNAcomplex (lipoplex) and protein-DNA complex.Unlike viral vectors, liposome-DNA complexes arenoninfectious, nonimmunogenic and exhibit low in     

The combination of bleomycin with suicide or interferon-β gene transfer is able to efficiently eliminate human melanoma tumor initiating cells

We explored the potential of a chemogene therapy combination to eradicate melanoma tumor initiating cells, key producers of recurrence and metastatic spread. Three new human melanoma cell lines, two obtained from lymph nodes and one from spleen metastasis were established and characterized. They were cultured as monolayers and spheroids and, in both spatial configurations they displayed sensitivity to single treatments with bleomycin (BLM) or human interferon-β (hIFNβ) gene or herpes simplex virus thymidine kinase/ganciclovir suicide gene (SG) lipofection. However, the combination of bleomycin with SG or hIFNβ gene transfer displayed greater antitumor efficacy. The three cell lines exhibited a proliferative behavior consistent with melan A and gp100 melanoma antigens expression, and BRAF V600E mutation. BLM and both genetic treatments increased the fraction of more differentiated and treatment-sensitive cells. Simultaneously, they significantly decreased the sub-population of tumor initiating cells. There was a significant correlation between the cytotoxicity of treatments with BLM and gene transfer and the fraction of cells exhibiting (i) high proliferation index, and (ii) high intracellular levels of reactive oxygen species. Conversely, the fraction of cells surviving to our treatments closely paralleled their (i) colony and (ii) melanosphere forming capacity. A very significant finding was that the combination of BLM with SG or hIFNβ gene almost abrogated the clonogenic capacity of the surviving cells. Altogether, the results presented here suggest that the combined chemo-gene treatments are able to eradicate tumor initiating cells, encouraging further studies aimed to apply this strategy in the clinic.     

Continuity matters: Examining the ‘information gap’ in transfer from Residential Aged Care,ambulance to emergency triage in southern Tasmania

BackgroundTransfer of older people from Residential Aged Care Facilities to Emergency Departments requires multiple comprehensive handovers across different services. Significant information gaps exist in transferred information despite calls for standards.AimTo investigate: (1) presence of minimum standard elements in the transfer text written by RACF nurses, paramedics and ED triage nurses, and (2) the transfer documentation used by services.MethodsWe analysed retrospective cross-sectional transfer narratives from the digital medical record system of an Australian tertiary referral hospital using the mnemonic SBAR (Situation, Background, Assessment Recommendation) as the measure of comprehensiveness. Transfer documents from 3 groups were also reviewed.FindingsInclusion of elements from SBAR was inconsistent across transfer. Rather, the written narratives focused on concerns relevant to the immediate priority, the type of information imposed by the document(s) in use, and clinical role of the author.ConclusionTransfer documentation from Residential Aged Care nurses, paramedics and ED triage nurses do not contain comprehensive information of older persons complex conditions. Better communication between non-affiliated organisations is needed to improve timely appropriate care for RACF residents.     

Skeletal myoblast-mediated gene transfer for hemophilia B gene therapy

Myoblast-mediated gene transfer approach has agreat potential to be developed into a durable genetherapy method for various diseases. To increase theexpression level of human factor Ⅸ (hFⅨ) in musclecells, we constructed a series of hFⅨ expression vectorswith the retroviral vector frame and examined their hFⅨexpression in skeletal muscle cells. Firstly, we introducedhFⅨ minigene (hFⅨ ml or hFⅨ m2), which contains atruncated first intron (1. 4 kb or 0. 3 kb) of hFⅨ gene