Biomedical subjects

Takehisa Matsuda

Publications and source records attributed to Takehisa Matsuda.

At least 37 records · Page 2Linked to original sources

PubMed2005

Poly(N-isopropylacrylamide) (PNIPAM)-grafted gelatin hydrogel surfaces: interrelationship between microscopic structure and mechanical property of surface regions and cell adhesiveness.

Poly(N-isopropylacrylamide)-grafted gelatin (PNIPAM-gelatin) serves as a temperature-induced scaffold at physiological temperature. This study was aimed at determining the effect of the graft architecture of thermoresponsive PNIPAM-gelatin on the surface topography and elastic modulus of the hydrogels prepared with different architectured PNIPAM-gelatins: the surface topography and elastic modulus were determined by atomic force microscopy (AFM). PNIPAM-gelatin surfaces showed an irregularly concavo-convex structure with a vertical interval of approximately 1 microm regardless of the weight ratio of PNIPAM to gelatin (P/G: 5.8, 12, and 18). The elastic moduli of hydrogels varied at measured sites. The mean elastic moduli of PNIPAM-gelatin with the lowest P/G were low, but increased with increasing P/G. Human umbilical vein endothelial cells adhered and spread on PNIPAM-gelatin hydrogels with the highest P/G, whereas reduced adhesion and nonspreading, round-shaped cells resided on the hydrogels with lower P/Gs. Interrelationship between elastic modulus and cell adhesion and spreading potentials were discussed from physicochemical and cellular biomechanical viewpoints.

Acrylamides↗

PubMed2005

Electrospun nano- to microfiber fabrics made of biodegradable copolyesters: structural characteristics, mechanical properties and cell adhesion potential.

Nano- to micro-structured biodegradable poly(L-lactide-co-epsilon-caprolactone) (PLCL) fabrics were prepared by electrospinning. Electrospun microfiber fabrics with different compositions of PLCL (mol% in feed; 70/30, 50/50, and 30/70), poly(L-lactide) (PLL) and poly(epsilon-caprolactone) (PCL) were obtained using methylene chloride (MC) as a solvent. The PLL microfiber exhibited a nanoscale-pore structure with a pore diameter of approximately 200-800 nm at the surface and subsurface regions, whereas such a surface structure was hardly observed in other polymers containing CL. The microfiber fabric made of PLCL 50/50 was elastomeric. Nanoscale-fiber fabrics with PLCL 50/50 (approx. 0.3 or 1.2 microm in diameter) were electrospun using 1,1,1,3,3,3-hexafluoro-2-propanol (HFIP) as a solvent. Mercury porosimetry showed that the decrease in the fiber diameter of the fabric decreased porosity, but increased fiber density and mechanical strength. Human umbilical vein endothelial cells (HUVECs) were adhered well and proliferated on the small-diameter-fiber fabrics (0.3 and 1.2 microm in diameter), both of which are dense fabrics, whereas markedly reduced cell adhesion, restricted cell spreading and no signs of proliferation were observed on the large-diameter-fiber fabric (7.0 microm in diameter). The potential biomedical application of electrospun PLCL 50/50 was discussed.

Absorbable Implants↗

PubMed2005

Poly(N-isopropylacrylamide) (PNIPAM)-grafted gelatin as thermoresponsive three-dimensional artificial extracellular matrix: molecular and formulation parameters vs. cell proliferation potential.

A series of poly(N-isopropylacrylamide)-grafted gelatins (PNIPAM gelatins) of three different graft densities (approx. 11, 22 and 34 graft chains per gelatin molecule) and three different molecular weights of their graft chains (molecular weight approximately 1.2 x 10(4), 5.0 x 10(4) and 1.3 x 10(5) g/mol) were prepared by multiple derivatization of dithiocarbamyl (DC) group in a gelatin molecule and subsequent iniferter (acts as an initiator, transfer-agent and terminator)-based photopolymerization of NIPAM. The weight ratio of PNIPAM graft chains to gelatin (P/G) varied from 1.4 to 49. Aqueous solutions of PNIPAM-gelatins showed thermo-responsiveness, depended on the graft density and the molecular weight of PNIPAM graft chain or P/G. Aqueous solutions (10 or 20%, w/v) of PNIPAM-gelatins with P/G of more than 5.8 were converted to gels at 37 degrees C. Focal plane images of PNIPAM-gelatin gels by confocal laser scanning microscopy revealed that the size of hydrophobically clustered aggregates increased with P/G, whereas the space of microvoids decreased with concentration. Compressive strain-stress measurements revealed that compressive strength of PNIPAM-gelatin increased with P/G. Bovine smooth muscle cells (SMCs)-entrapped gels were produced from PNIPAM-gelatin-containing cell-suspended medium solutions at 37 degrees C. The entrapped cells proliferated in the gel with P/G of more than 12. A higher cell proliferativity was obtained at low concentration (5%, w/v) and higher P/G (>18). Tissue formation composed of proliferative SMCs and cell-secreted extracellular matrices (collagen) was obtained at 14 days incubation. The inter-relationship between the molecular parameters of PNIPAM-gelatin, internal structural features and cell proliferation potential was discussed.

Acrylic Resins↗

PubMed2004

Novel strategic therapeutic approaches for prevention of local recurrence of pancreatic cancer after resection: trans-tissue, sustained local drug-delivery systems.

Local recurrence and hepatic metastasis are still the major causes of death of patients who have undergone resection for pancreatic cancer. To decrease the incidence of local recurrence, we have proposed and devised several trans-tissue and local delivery systems, all of which could be applied immediately after surgery at the resected sites: (1) System I: a drug-loaded photocured gelatinous tissue-adhesive gel (bioactive substance reservoir) that enables the sustained release of a drug, protein, or gene-encoding adenovirus, (2) System II: an anti-cytokine antibody-fixed photocured gelatinous, tissue-adhesive gel (cytokine barrier) that prevents cytokine permeation into the resected tissue, (3) System III: a gene-modified cell sheet that enables the sustained release of a very costly protein produced by gene-transduced cells and (4) System IV: a percutaneous drug-delivery device that enables continuous drug infusion and easy removal from the body. This review article is a summary of our several years of efforts and attempts, which are composed of integrated disciplines including active biomaterials and genetic- and tissue-engineerings, to overcome the recurrence of pancreatic cancer. Here, we outline our proposed strategies and therapeutic devices/materials and discuss their potential therapeutic effectiveness, promises and challenges in the clinical settings.

Antineoplastic Agents↗

PubMed2004

Extracorporeal cardiac shock wave therapy markedly ameliorates ischemia-induced myocardial dysfunction in pigs in vivo.

BACKGROUND: Prognosis of ischemic cardiomyopathy still remains poor because of the lack of effective treatments. To develop a noninvasive therapy for the disorder, we examined the in vitro and vivo effects of extracorporeal shock wave (SW) that could enhance angiogenesis. METHODS AND RESULTS: SW treatment applied to cultured human umbilical vein endothelial cells significantly upregulated mRNA expression of vascular endothelial growth factor and its receptor Flt-1 in vitro. A porcine model of chronic myocardial ischemia was made by placing an ameroid constrictor at the proximal segment of the left circumflex coronary artery, which gradually induced a total occlusion of the artery with sustained myocardial dysfunction but without myocardial infarction in 4 weeks. Thereafter, extracorporeal SW therapy to the ischemic myocardial region (200 shots/spot for 9 spots at 0.09 mJ/mm2) was performed (n=8), which induced a complete recovery of left ventricular ejection fraction (51+/-2% to 62+/-2%), wall thickening fraction (13+/-3% to 30+/-3%), and regional myocardial blood flow (1.0+/-0.2 to 1.4+/-0.3 mL x min(-1) x g(-1)) of the ischemic region in 4 weeks (all P<0.01). By contrast, animals that did not receive the therapy (n=8) had sustained myocardial dysfunction (left ventricular ejection fraction, 48+/-3% to 48+/-1%; wall thickening fraction, 13+/-2% to 9+/-2%) and regional myocardial blood flow (1.0+/-0.3 to 0.6+/-0.1 mL x min(-1) x g(-1)). Neither arrhythmias nor other complications were observed during or after the treatment. SW treatment of the ischemic myocardium significantly upregulated vascular endothelial growth factor expression in vivo. CONCLUSIONS: These results suggest that extracorporeal cardiac SW therapy is an effective and noninvasive therapeutic strategy for ischemic heart disease.

Animals↗

PubMed2004

Confocal imaging of biofilm formation process using fluoroprobed Escherichia coli and fluoro-stained exopolysaccharide.

We developed a novel method of evaluating biofilm architecture on a synthetic material using green fluorescent protein-expressing Escherichia coli and red fluorescence staining of exopolysaccharides. Confocal laser scanning microscopy observation revealed the time course of the change in the in situ three-dimensional structural features of biofilm on a polyurethane film without structural destruction: initially adhered cells are grown to form cellular aggregates and secrete exopolysaccharides. These cells were spottily distributed on the surface at an early incubation time but fused to form a vertically grown biofilm with incubation time. Fluorescence intensity, which is a measure of the number of cells, determined using a fluorometer and biofilm thickness determined from confocal laser scanning microscopy vertical images were found to be effective for quantification of time-dependent growth of biofilms. The curli (surface-located fibers specifically binding to fibronectin and laminin)-producing Escherichia coli strain, YMel, significantly proliferated on fibronectin-coated polyurethane, whereas the curli-deficient isogenic mutant, YMel-1, did not. The understanding of biofilm architecture in molecular and morphological events and new fluorescence microscopic techniques may help in the logical surface design of biomaterials with a high antibacterial potential.

Bacterial Adhesion↗

PubMed2004

Substrate-dependent cellular behavior of Swiss 3T3 fibroblasts and activation of Rho family during adhesion and spreading processes.

Recent biochemical studies revealed that intracellular Rho guanosine triphosphatases (Rho, Rac1, and Cdc42) are key regulatory molecules that link surface receptors to cytoskeletal organization and regulation of cell shape/morphology/motility. In this study, Swiss 3T3 fibroblasts were cultured on three representative substrates [tissue culture polystyrene dishes, nontreated polystyrene, and poly(ethylene terephthalate)] for 24 h after plating. Time-dependent changes in cell shape, morphology, cytoskeletal dynamics, and motility as well as Rho family activities were determined on each substrate. The cells on tissue culture polystyrene and on poly(ethylene terephthalate), which induced rapid and relatively rapid cell spreading, respectively, expressed Rac1 and Cdc42 activities continuously during the observation period. In contrast, such activities were suppressed in cells on polystyrene, which induced slow spreading but the highest cell motility compared with the other two substrates. Although a clear-cut relationship between cellular behavior and Rho family activation was not obtained, substrate-dependent coordinated control of cellular activities by Rho family is discussed.

Animals↗

PubMed2004

In vivo evaluation of poly(N-isopropylacrylamide) (PNIPAM)-grafted gelatin as an in situ-formable scaffold.

We examined whether poly(N-isopropylacrylamide)-grafted gelatin (PNIPAM-gelatin) with a lower critical solution temperature of approximately 34 degrees C, which was prepared by quasi-living radical graft polymerization, can serve as an in situ-formable three-dimensional extracellular matrix or cell scaffold. A mixture of fibroblasts stained with fluorescent dye and PNIPAM-gelatin in Dulbecco's modified Eagle's medium solution was injected into the subcutaneous tissue of Wistar rats, and immediately formed a white, opaque cell-incorporated gel. Fibroblasts immediately after injection were spherical in shape and were homogeneously distributed in the gel. Fibroblasts in the gel 2 weeks after injection had spread and proliferated. One day after injection, many macrophages and neutrophiles were observed around the gel. As the implantation period proceeded, the inflammation reaction subsided. One week after injection, fibroblasts in the native tissue and macrophages migrated into the gel. From 6 to 12 weeks after injection, some degree of calcification in the solid tissue was intermittently observed. The weight of the gel 6 weeks after implantation was reduced to almost one-half of the weight of the originally injected sample. The potential usefulness of PNIPAM-gelatin as an injectable scaffold is discussed.

Acrylic Resins↗

PubMed2004

A device for the spatio-regional delivery of a photocurable drug formulation.

We devised a new transtissue drug-delivery system, based on a multiple-needle-arrayed injector that has 36 long and short needles on the needle head, to administer the drug into local points of the target tissue at a well-controlled depth and pitch. A preliminary in vitro study, focusing the time-dependent depth profiling of protein injected in agarose gel as a model tissue using confocal laser scanning microscope, was conducted to evaluate the performance of the multiple-needle-arrayed injector coupled with photoreactive gelatin (styrenated gelatin: St-gelatin) as the sustained-release vehicle. Rhodamine-conjugated albumin, which was mixed with the St-gelatin buffer solution, was the model drug of the in vitro study, and the mixture was injected into agarose gel using the multiple-needle-arrayed injector by single injection, followed by visible-light irradiation to photocure the gelatin solution. Time-dependent distribution from the injected material into the surrounding agarose gel was observed using a confocal laser scanning microscope up to seven days. Injection of the drug material and concomitant withdrawal of the syringe (termed multirod method) enabled the long- and short-rod-like injections into the agarose gel at the same locations of the injected sites. The model drug gradually diffused throughout the agarose gel. In an in vivo study, the comparison of the efficacy of the angiogenic protein (bFGF: 10 microg for each) with placebo was performed using the non-ischemic hind limb model of rabbits. Four weeks after injection, a significant increase in the number of angiogenic capillaries was observed in the mixed St-gelatin/bFGF group compared with that of placebo. The multiple-needle-arrayed injector coupled with a sustained-release vehicle may be an effective drug delivery system for realizing the spatio-regional distribution of angiogenic protein.

Animals↗

PubMed2004

In situ-formed, tissue-adhesive co-gel composed of styrenated gelatin and styrenated antibody: potential use for local anti-cytokine antibody therapy on surgically resected tissues.

Styrenated antibody (ST-Ab) and styrenated gelatin (ST-gelatin) were prepared by condensation reaction of antibody or gelatin with 4-vinylbenzoic acid, respectively. The affinity loss of ST-Ab to its antigen was minimal. ST-Ab and ST-gelatin were copolymerized with by visible-light irradiation in the presence of a water-soluble camphorquinone as a photoinitiator to produce a tissue-adhesive, in situ-formed co-gel of ST-gelatin and ST-Ab. The amount of non-reacted ST-Ab released from the co-gel of ST-gelatin and ST-Ab into the medium was minimal. The confocal laser scanning microscopy observation showed that local accumulation of rhodamine-labeled bovine serum albumin (BSA) as a model antigen was noticed in the surface-to-subsurface region of the co-gel of ST-gelatin and anti-BSA ST-Ab, indicating that the gel prevented the permeation of BSA into the gel. In invasion double chamber assay using anti-hepatocyte growth factor (HGF) antibody, the co-gel prevented HGF-dependent invasion of pancreatic cancer cells. The discussion was made for potential application of an in situ-formed tissue-adhesive co-gel of ST-gelatin and ST-Ab, developed in this study, as a cytokine-barrier on a surgically resected tissue where cancer cells might still remain after resection of cancerous tissue.

Antibodies↗

PubMed2004

Recent progress of vascular graft engineering in Japan.

The development of a small-diameter vascular graft has long been awaited. This review covers research activities, achievements and progress on vascular engineering in Japan, which was conducted over the last decade. The article includes recently developed experimental scaffolds, biologically active artificial extracellular matrices (ECMs) or non-fouling synthetic coatings, cell sourcing including the autologous vascular cell type, endothelial progenitor cells and genetically-engineered, temporary endothelial-like cells. The discussions were presented from biomechanical, biomaterial, cellular and tissue aspects. Once the mechano-biological and biologically active extracellular milieus are established in a designed vascular graft, the functional, structural and mechanical tissue morphogenesis and adaptation of implanted vascular grafts may proceed with implantation duration, and the spatio-temporal tissue modulations at cytokine, cellular, ECM levels under physiological stress proceed to regenerate vascular tissue architecture. The ultimate solution to a small-diameter vascular graft should be realized by optimal combinations of these factors.

Animals↗

PubMed2004

Development of an implantable undulation type ventricular assist device for control of organ circulation.

It is well known that a rotary blood pump (RP) is effective as a small ventricular assist device (VAD). It might be still more effective if pulsation was available. The undulation pump (UP), which is a type of small RP, can also produce pulsation. In Japan, a development project for an implantable type UP ventricular assist device (UPVAD) is now advanced. Six universities and some companies together have been in charge of the development project for 5 years. In this study, the influence which the UP under development has on circulation in internal organs was investigated. Goats with the same weight as an average Asian person were used for the experiment. The left chest cavity was opened after resection of the fourth rib and the heart was approached. A cannula was inserted in the left ventricle from the apex. An outflow cannula was inserted into the left descending aorta. Heart muscle was excised using a newly developed puncher. The UPVAD was implanted using a left-heart bypass system. The myocardial blood flow, carotid arterial blood flow, and the kidney blood flow were recorded together with an electrocardiogram, blood pressure, and the flow rate. In these animal experiments, the blood circulation dynamic state was stabilized and sufficient support of the left heart was observed. Myocardial blood flow, carotid arterial flow, and a kidney blood flow increase resulting from UPVAD support was observed. Often the problem of multiple organ failure is important at the time of clinical application of a ventricular assist device. Assisting circulation to internal organs is important for prevention of multiple organ failure. It was concluded that the UPVAD might be useful for prevention of multiple organ failure.

Animals↗

PubMed2004

Poly(N-isopropylacrylamide)-grafted gelatin as a thermoresponsive cell-adhesive, mold-releasable material for shape-engineered tissues.

Poly(N-isopropylacrylamide)-grafted gelatin (PNIPAM-gelatin) can be used as a thermoresponsive cell-adhesive matrix and mold-releasable material for shape-engineered tissues. An example of such a tissue with predetermined shape is realized by fabrication of a tubular endothelial cell construct. A solution containing a mixture of PNIPAM-gelatin and PNIPAM was coated on the luminal surface of a glass capillary tube. After air-drying, endothelial cells were seeded and cultured for four days at 37 degrees C. The infusion of the culture medium into the tube at 20 degrees C resulted in the spontaneous detachment and removal of a tubular vascular tissue composed of endothelial cells and supramolecularly organized extracellular matrices produced by endothelial cells on the basal side of the tissue. The potential use of a thermoresponsive cell-adhesive and mold-releasable material in complex-shaped tissue-engineered devices is discussed.

Acrylic Resins↗

PubMed2004

Photofabricated gelatin-based nerve conduits: nerve tissue regeneration potentials.

There is a strong demand for development of nerve guide conduit with prompt nerve regeneration potential for injury-induced nerve defect. Prior to study on nerve tissue engineering using Schwann cells or nerve stem cells, the effectiveness of photofabricated scaffolds based on photocurable gelatin was examined. This study describes the evaluation of in vivo nerve tissue regeneration potentials of three custom-designed and -fabricated prostheses (inner diameter, 1.2 mm; outer diameter, 2.4 mm; wall thickness, 0.60 mm; and length, 15 mm) made of photocured gelatin: a plain photocured gelatin tube (model I), a photocured gelatin tube packed with bioactive substances (laminin, fibronectin, and nerve growth factor) coimmobilized in a photocured gelatin rod (model II), and a photocured gelatin tube packed with bioactive substances coimmobilized in multifilament fibers (model III). These prostheses were implanted between the proximal and distal stumps 10 mm of the dissected right sciatic nerve of 70 adult male Lewis rats for up to 1 year. The highest regenerative potentials were found using the model III prosthesis, followed by the model II prosthesis. Markedly retarded neural regeneration was observed using the model I prosthesis. These were evaluated from the viewpoints of functional recovery, electrophysiological responses, and tissue morphological regeneration. The significance of the synergistic cooperative functions of multifilaments, which serve as a platform that provides contact guidance to direct longitudinal cell movement and tissue ingrowth and as a cell adhesive matrix with high surface area, and immobilized bioactive substances, which enhance nerve regeneration via biological stimulation, is discussed.

Animals↗

PubMed2003

Trans-tissue, sustained release of gemcitabine from photocured gelatin gel inhibits the growth of heterotopic human pancreatic tumor in nude mice.

PURPOSE: Although gemcitabine, a deoxycytidine analogue, recently demonstrated improvements in the response rate for pancreatic cancer, the median survival for patients is limited to 4-6 months. The purpose of the present study was to develop trans-tissue delivery of gemcitabine, which is based on photocured gelatin gel immobilized with gemcitabine, and to validate whether such a system inhibits the growth of the pancreatic tumor in vivo. EXPERIMENTAL DESIGN: The in vitro release profile of gel-embedded gemcitabine from a gel was examined based on in vitro chemosensitivity of AsPC1 cell (human pancreatic cancer cell line) for gemcitabine. The permeation of gel-embedded rhodamine B (used as a model drug) into tissues and inhibitory effect of tumor growth of photocured gelatin gel immobilized with gemcitabine were examined using in vivo s.c. tumor model of athymic mice. RESULTS: The release profile was characterized as an initial burst of release, followed by a gradual release, irrespective of gelatin concentration. Rhodamine B permeated into the tumor and retained for at least 10 days. Photocured gelatin gel immobilized with gemcitabine significantly reduced the tumor volume compared with gemcitabine injection. Therapeutic success was correlated with decreased cell proliferation and increased cell apoptosis in tumor cells, supported by proliferating cell nuclear antigen and terminal deoxynucleotidyltransferase-mediated nick end labeling staining. Blood analysis and body weight measurement showed that little side effect was observed in this therapy. CONCLUSIONS: In situ trans-tissue gemcitabine delivery on the tissue with possibly remnant cancer cells using the drug-releasing matrix developed here is expected to reduce the rate of local recurrence for patients with pancreatic cancer.

Animals↗

PubMed2003

Long-term inhibition of Rho-kinase suppresses neointimal formation after stent implantation in porcine coronary arteries: involvement of multiple mechanisms.

OBJECTIVE: We recently demonstrated that Rho-kinase, an effector of the small GTPase Rho, is substantially involved in the pathogenesis of arteriosclerosis. In this study, we examined whether Rho-kinase is also involved in in-stent restenosis and if so, what mechanism is involved. METHODS AND RESULTS: Pigs underwent stent implantation in the left coronary artery with or without administration of fasudil (30 mg/kg per day orally), a specific Rho-kinase inhibitor, starting 2 days before the procedure for a duration of 4 weeks. On day 28, reductions in coronary diameter and neointimal formation associated with macrophage accumulation, collagen deposition, and transforming growth factor (TGF)-beta1 expression were noted at the stent site, and all were significantly suppressed by fasudil. On day 7, fasudil significantly increased the frequency of TUNEL-positive apoptotic cells, while it tended to reduce that of bromodeoxyuridine-positive proliferating cells in the neointima. Western blot analysis on day 7 demonstrated that phosphorylations of the ezrin/radixin/moesin family (a marker of Rho-kinase activity in vivo) and protein expression of monocyte chemoattractant protein-1and bcl-2 were upregulated at the stent site and were significantly suppressed by fasudil. CONCLUSIONS: These results indicate that long-term inhibition of Rho-kinase suppresses in-stent neointimal formation by multiple mechanisms, including reduced vascular inflammation, enhanced apoptosis, and decreased collagen deposition.

1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine↗

PubMed2003

Novel therapeutic strategy for prevention of malignant tumor recurrence after surgery: Local delivery and prolonged release of adenovirus immobilized in photocured, tissue-adhesive gelatinous matrix.

We have been developing a new gene delivery method using a styrenated gelatin-based tissue-adhesive matrix that allows in situ adenovirus-immobilized gel formation on living tissue and sustained virus release to permeate carcinoma tissue. Styrenated gelatin was synthesized by the condensation reaction of gelatin with 4-vinylbenzoic acid. Aqueous styrenated gelatin solution premixed with AdLacZ, adenovirus encoding beta-galactosidase cDNA, and carboxylated camphorquinone (CQ) as a photoinitiator was irradiated with visible light to form a styrenated gelatin gel. The in vitro adenovirus release from the styrenated gelatin gel to a medium strongly depended not on styrenated gelatin concentration but on CQ concentration. Maximal beta-galactosidase expression was observed on day 1, followed by a rapid decrease that continued up to 1 month for a styrenated gelatin gel prepared with a low styrenated gelatin concentration and a low CQ concentration. Dose-dependent reduced expression of beta-galactosidase activity with increasing CQ under photoirradiation was observed. AdLacZ-immobilized styrenated gelatin gel was formed on a hybrid tissue, which is a cell traction-induced collagenous gel entrapped with fibroblasts, and lacZ gene expression of fibroblasts in the hybrid tissue was observed for more than one month. The result of this in vitro model experiment implies that the tissue-adhesive styrenated gelatin may be applicable for the delivery of adenovirus encoding cDNA for tumor dormancy therapy into malignant tissue to prevent tumor recurrence after surgery when cDNA is properly selected.

Adenoviridae↗

PubMed2003

Cell-based protein delivery system for the inhibition of the growth of pancreatic cancer: NK4 gene-transduced oral mucosal epithelial cell sheet.

PURPOSE: Pancreatic resection for pancreatic cancer is the only curative modality, but the high incidence of local recurrence after surgery results in a very poor prognosis. This study aims to develop a new therapeutic tool that could inhibit the growth of remnant cancer cells, which is based on local delivery of NK4 (hepatocyte growth factor antagonist) secreted from an NK4 gene-transduced oral mucosal epithelial cell (OMEC) sheet (NK4-sheet), which is adhered to the resected surface. EXPERIMENTAL DESIGN: OMECs, harvested and cultured according to 3T3 feeder layer technique, were seeded on a collagen mesh-overlayered, biodegradable VICRYL mesh to produce an OMEC sheet. NK4 gene transduction was mediated by recombinant adenovirus (Ad-NK4). Applicability of OMECs for cell-based NK4 delivery was examined. An experimental model using nude mice was established to determine the effect of an NK4-sheet on both tumor growth and angiogenesis. RESULTS: NK4 secreted from Ad-NK4-transduced OMECs suppressed MRC-5-induced invasion of pancreatic cancer cell lines. Heterotopically implanted gene-transduced OMECs remained for >/==" BORDER="0">10 days while gradually decreasing. NK4-sheets inhibited both angiogenesis and tumor growth in vivo. CONCLUSION: Autologous OMEC was found to be suited to this purpose because of no secretion of hepatocyte growth factor, ease in harvesting from a patient, reasonably high proliferation potential, and no immune reaction. Although NK4-sheets under development exhibited a low level and short period of NK4 secretion, it is expected that this system may have a great potentiality of protein delivery system to target tissue at clinical situations when it is loaded with multilayered OMECs.

Adenoviridae↗