Recombinant E1-deleted adenoviral vectors induce apoptosis in a rat airway epithelial mucous goblet cell line

Elimination of rheumatoid synovium in situ using a Fas ligand 'gene scalpel'

Surgical synovectomy to remove the inflammatory synovium can temporarily ameliorate rheumatoid inflammation and delay the progress of joint destruction. An efficient medically induced programmed cell death (apoptosis) in the rheumatoid synovium might play a role similar to synovectomy but without surgical tissue damage. Gene transfer of Fas ligand (FasL) has increased the frequency of apoptotic cells in mouse and rabbit arthritic synovium. In this study, we investigated whether repeated FasL gene transfer could remove human inflammatory synovial tissue in situ and function as a molecular synovectomy. Briefly, specimens of human synovium from joint replacement surgeries and synovectomies of rheumatoid arthritis (RA) patients were grafted subcutaneously into male C.B-17 severe combined immunodeficiency (SCID) mice. Injections of a recombinant FasL adenovirus (Ad-FasL) into the grafted synovial tissue at the dosage of 10(11) particles per mouse were performed every two weeks. Three days after the fifth virus injection, the mice were euthanized by CO2 inhalation and the human synovial tissues were collected, weighed and further examined. Compared to the control adenovirus-LacZ (Ad-LacZ) and phosphate buffered saline (PBS) injected RA synovium, the Ad-FasL injected RA synovium was dramatically reduced in size and weight (P < 0.005). The number of both synoviocytes & mononuclear cells was significantly reduced. Interestingly, an approximate 15-fold increased frequency of apoptotic cells was observed in RA synovium three days after Ad-FasL injection, compared with control tissues. In summary, our in vivo investigation of gene transfer to human synovium in SCID mice suggests that repeated intra-articular gene transfer of an apoptosis inducer, such as FasL, may function as a 'gene scalpel' for molecular synovectomy to arrest inflammatory synovium at an early stage of RA.

A potency assay for a replication incompetent adenovirus type 5 carrying a human fgf-4 gene

A bioassay that measures the potency of the FGF-4 transgene carried by a replication incompetent adenovirus type 5, Ad5FGF-4, was developed on ARPE-19 cells. The assay is carried out in a microtiter plate format and measures cellular proliferation following infection of ARPE-19 cells with a serial dilution of Ad5FGF-4. Proliferation is measured as a percentage increase in absorbance reading in relation to a mock-infected control. Ad5LacZ and Ad5FGF-4 viruses treated similarly to the test sample are included as negative and positive controls, respectively. The increased absorbance reading resulting from infection with the virus correlates with FGF-4 production as determined by an FGF-4 enzyme-linked immunosorbent assay, an increase in de novo DNA synthesis as measured by BrdU incorporation, and an increase in the total cell number. The assay shows a dose-dependent response and is capable of evaluating the stability of Ad5FGF-4. A sample being tested is compared with a reference standard, and the relative potency value is obtained by a parallel line analysis of the dose-response curve of the test article in relation to the reference standard. Therefore, this procedure can be used as an in vitro efficacy-indicating assay, demonstrating that the FGF-4 transgene product carried by Ad5FGF-4 is biologically active.

Variables pertinent to the efficiency of adeno-associated virus (AAV) vectors mediated gene transfer to human vascular endothelial cells

Factors influencing adeno-associated virus (AAV) - mediated gene transfer to endothelial cells are not fully determined. We tested the variables pertinent to the efficiency of AAV-mediated gene transfer to human vascular endothelial cells (HUVEC) including: (i) kinetics of transduction efficiency of LacZ gene to HUVEC, (ii) the concentration and volume of vector-containing medium, (iii) the period of incubation time of AAV vectors with HUVEC, (iv) the target cell density/proliferation, (v) the duration of transgene expression. There is a dose-response relationship between moi of vectors and transduction efficiency in HUVEC. The higher moi of AAV vectors achieved more than 80% of transduction efficiency in cultured HUVEC. AAV vectors showed incubation time dependent increase in transduction efficiency of LacZ gene to the HUVEC up to 24 h of vector exposure. The foreign gene of AAV vectors preferably transduces the lower density of cells being proliferated. These results indicate that AAV-vector is efficient for gene transfer to HUVEC, and higher moi of vectors or a longer period exposure of vectors to proliferating HUVEC can facilitate efficient tranduction of foreign gene into human vascular endothelial cells in vitro.

Recombinant adeno-associated virus vectors efficiently transduce foreign gene into bovine aortic endothelial cells: comparison with adenovirus vectors

Because the features and kinetics of adeno-associated virus (AAV)-mediated gene transfer to endothelial cells (EC) are yet to be ultimately determined, we tested variables pertinent to the efficiency of AAV-mediated gene transfer to bovine aortic endothelial cells (BAEC). The variables with AAV vectors were compared with the better characterized adenovirus (Ad) vectors. There is a dose-response relationship between multiplicity of infection (moi) of AAV or Ad vectors and transduction efficiency in BAEC. The higher moi of AAV vectors achieved more than 80% of transduction efficiency in cultured BAEC. AAV and Ad vectors showed an incubation-time-dependent increase in transduction efficiency of LacZ gene to the BAEC up to 12 h of vector exposure. Although the similar kinetics of transduction efficiency of LacZ gene to BAEC was found in both vectors, the duration of gene expression was longer in AAV vector than that in Ad vectors in vitro. These results indicate that AAV-vector is efficient for gene transfer to EC, and higher moi of vectors or a longer period exposure of vectors to EC can facilitate efficient transduction of a foreign gene into cultured EC. For the duration of gene expression, the AAV vectors may be better than Ad vectors.