hIL-10 Gene Research Articles

Safe Procedure for Efficient Hydrodynamic Gene Transfer to Isolated Porcine Liver in Transplantation.

Although calcineurin inhibitors are very effective as immunosuppressants in organ transplantation, complete graft acceptance remains as a challenge. Transfer of genes with immunosuppressant functions could contribute to improving the clinical evolution of transplantation. In this sense, hydrodynamic injection has proven very efficacious for liver gene transfer. In the present work, the hIL-10 gene was hydrofected 'ex vivo' to pig livers during the bench surgery stage, to circumvent the cardiovascular limitations of the procedure, in a model of porcine orthotopic transplantation with a 10-day follow-up. We used IL-10 because human and porcine proteins can be differentially quantified and for its immunomodulatory pleiotropic functions. Safety (biochemical parameters and histology), expression efficacy (RNA transcription and blood protein expression), and acute inflammatory response (cytokines panel) of the procedure were evaluated. The procedure proved safe as no change in biochemical parameters was observed in treated animals, and human IL-10 was efficaciously expressed, with stationary plasma protein levels over 20 pg/mL during the follow-up. Most studied cytokines showed increments (interferon-α, IFN-α; interleukin-1β, IL-1β; tumor necrosis factor α, TNFα; interleukin-6, IL-6; interleukin-8, IL-8; interleukin-4, IL-4; and transforming growth factor-β, TGF-β) in treated animals, without deleterious effects on tissue. Collectively, the results support the potential clinical interest in this gene therapy model that would require further longer-term dose-response studies to be confirmed.

Efficacy of Combined in-vivo Electroporation-Mediated Gene Transfer of VEGF, HGF, and IL-10 on Skin Flap Survival, Monitored by Label-Free Optical Imaging: A Feasibility Study.

Preventing surgical flaps necrosis remains challenging. Laser Doppler imaging and ultrasound can monitor blood flow in flap regions, but they do not directly measure the cellular response to ischemia. The study aimed to investigate the efficacy of synergistic in-vivo electroporation-mediated gene transfer of interleukin 10 (IL-10) with either hepatocyte growth factor (HGF) or vascular endothelial growth factor (VEGF) on the survival of a modified McFarlane flap, and to evaluate the effect of the treatment on cell metabolism, using label-free fluorescence lifetime imaging. Fifteen male Wistar rats (290–320 g) were randomly divided in three groups: group-A (control group) underwent surgery and received no gene transfer. Group-B received electroporation mediated hIL-10 gene delivery 24 h before and VEGF gene delivery 24 h after surgery. Group-C received electroporation mediated hIL-10 gene delivery 24 h before and hHGF gene delivery 24 h after surgery. The animals were assessed clinically and histologically. In addition, label-free fluorescence lifetime imaging was performed on the flap. Synergistic electroporation mediated gene delivery significantly decreased flap necrosis (P = 0.0079) and increased mean vessel density (P = 0.0079) in treatment groups B and C compared to control group-A. NADH fluorescence lifetime analysis indicated an increase in oxidative phosphorylation in the epidermis of the group-B (P = 0.039) relative to controls. These findings suggested synergistic in-vivo electroporation-mediated gene transfer as a promising therapeutic approach to enhance viability and vascularity of skin flap. Furthermore, the study showed that combinational gene therapy promoted an increase in tissue perfusion and a relative increase in oxidative metabolism within the epithelium.

Effect of hIL10 Naked DNA Delivery on Swine Heart Tissue after Acute Infarct

Purpose: Myocardial infarct mediates an inflammatory response whose intensity limits the recovery of the damaged tissue and its function. In the present work, we evaluate the efficacy of immunomodulatory hIL10 gene hydrofection on acute myocardial infarct in pig. Methods: Pigs recently infarcted by right coronary artery block were injected with 50 ml saline solution containing the naked gene at 2 or 7 ml/s through coronary sinus. Blood samples were collected from coronary sinus before gene injection, 2 and 72 hours later for protein quantification. Heart tissue samples from normal and infarcted tissue were collected 72 hours post-transfection to evaluate the efficiency of gene delivery and decoding The results: hIL10 protein translation yielded more than 200 protein molecules/cell in normal tissue and was always higher than in infarcted areas. Coronary sinus plasma concentration of hIL10 protein reached 50 pg/ml as average. The histopathological evaluation of peri-infarct and infarct areas showed that interleukin 10 hydrofection mediated anti-inflammatory effects, as evidenced by reduced edema and cell infiltration. Conclusions: Heart hydrofection of hIL10 gene in infarct-induced pigs mediates local expression of cytokine in normal and infarcted tissue, resulting in reduced acute response triggered by the ischemic episode induced experimentally.

Effect of local hIL-10 gene therapy on experimental periodontitis in ovariectomized rats

Objective: To investigate the effect of local hIL-10 gene therapy on experimental periodontitis in rats and to elucidate the mechanism underlying this effect.Material and methods: Experimental periodontitis was induced in ovariectomized (OVX) rats using a silk ligature. We then injected 5 μg of hIL-10 plasmid with 5 μl of liposomes or 5 μg of vector plasmid with 5 μl of liposomes into the palatal side of the gingival mucosa of the upper left second molar once every two days. The rats were killed 48 hours after the seventh injection. The body weight; bone mineral density of the whole body, pelvis and spine; resorption of the alveolar bone; and number of cytokine-positive cells were measured to determine the effects of hIL-10 on the periodontal tissue.Results: hIL-10 was expressed in periodontal tissues after local gene delivery. The expressed hIL-10 protein inhibited alveolar bone resorption and downregulated IL-1β, IL-6, TNF-α, RANKL and MMP-8 in the periodontal ligament in the root furcation region.Conclusions: Local hIL-10 gene transfer suppressed alveolar bone resorption in OVX rats, and this effect was probably associated with the decline in the expression of pro-inflammatory cytokines in the periodontal tissues.

Human Interleukin-10 Naked DNA Delivery to Infarcted Pig Heart by Catheter Mediated Retrograde Injection in Coronary Sinus

Background: Interleukin-10 (IL-10) has proved to be important in recovery after acute myocardial infarction; increasing its expression in infarcted or bystander tissue therefore could be of great importance. Hydrodynamic DNA injection has been found to be very efficient in transferring genes to the liver of small animals, but the procedure is very aggressive and must be made compatible with clinical practice in a milder but not less efficient way. The present work evaluates the efficiency of noninvasive catheterization of the coronary sinus for human IL-10 gene transfer to infarcted and non-infarcted pig heart, with therapeutic production of the human protein. Methods: Myocardial infarction was induced in pigs by a catheter-based approach to occlude the left anterior descending artery. After myocardial infarction verification, two catheters were placed in the coronary sinus, one of them to block blood circulation and the other to retrogradely inject 50 ml of a saline solution of DNA (20 μg/ml) containing the hIL-10 gene, and testing different flow rate conditions (control, 2, 5 and 10 ml/s). Results: Therapeutic levels of hIL-10 protein were found in coronary sinus blood 2 and 72 hours after cathetermediated hydrofection at 5 and 10 ml/s flow rate. Molecular analyses to evaluate the delivered DNA, its transcription to RNA and translation were also performed, and data were expressed as copies per cell. Conclusion: Catheter-mediated gene transfer through the coronary sinus is a mild and well-tolerated procedure that achieves protective hIL-10 protein levels, which could minimize the inflammatory response after myocardial infarction.

Recombinant protein yield in rice seed is enhanced by specific suppression of endogenous seed proteins at the same deposit site

Human IL-10 (hIL-10) is a therapeutic treatment candidate for inflammatory allergy and autoimmune diseases. Rice seed-produced IL-10 can be effectively delivered directly to gut-associated lymphoreticular tissue (GALT) via bio-encapsulation. Previously, the codon-optimized hIL-10 gene was expressed in transgenic rice with the signal peptide and endoplasmic reticulum (ER) retention signal (KDEL) at its 5' and 3' ends, respectively, under the control of the endosperm-specific glutelin GluB-1 promoter. The resulting purified hIL-10 was biologically active. In this study, the yield of hIL-10 in transgenic rice seed was improved. This protein accumulated at the intended deposition sites, which had been made vacant through the selective reduction, via RNA interference, of the endogenous seed storage proteins prolamins or glutelins. Upon suppression of prolamins that were sequestered into ER-derived protein bodies (PB-I), hIL-10 accumulation increased approximately 3-fold as compared to rice seed with no such suppression and reached 219 μg/grain. In contrast, reducing the majority of the glutelins stored in protein-storage vacuoles (PB-II) did not significantly affect the accumulation of hIL-10. Considering that hIL-10 is synthesized in the ER lumen and subsequently buds off in ER-derived granules called IL-10 granules in a manner similar to PB-Is, these results indicate that increases in the available deposition space for the desired recombinant proteins may be crucial for improvements in yield. Furthermore, efficient dimeric intermolecular formation of hIL-10 by inhibiting interaction with Cys-rich prolamins also contributed to the enhanced formation of IL-10 bodies. Higher yield of hIL-10 produced in rice seeds is expected to have broad application in the future.

Adenovirus-Mediated Dual Gene Expression of Human Interleukin-10 and Hepatic Growth Factor Exerts Protective Effect Against CCl4-Induced Hepatocyte Injury in Rats

Hepatocyte injury is a common pathological cause of various liver diseases. Due to a lack of an effective preventive treatment, gene therapy has become an interesting approach to prevent and alleviate liver injury. A protective effect of adenovirus-mediated dual gene expression of human interleukin-10 (hIL-10) and human hepatocyte growth factor (hHGF) was investigated against tetrachloromethane (CCl(4))-induced hepatocyte injury in rats. An adenoviral vector carrying the hIL-10 and hHGF genes was constructed, and its protective effect against rat hepatocyte injury was investigated both in vivo and in vitro. In the in vitro CCl(4)-induced cell injury model, simultaneous transfection of hIL-10 and hHGF genes via an adenoviral vector resulted in production of anti-hepatocyte biological factors by an autocrine mechanism, then significantly improved hepatocyte viability. In the in vivo rat model, synergistic effects of these two gene products protected hepatocytes from damage by reducing the CC1(4)-induced hepatocyte degeneration, hepatic fibrosis, and intrahepatic inflammatory cell infiltration, thereby preserving liver function. Adenovirus-mediated dual gene expression of hIL-10 and hHGF effectively protected against liver damage by likely regulating immune responses to reduce hepatocyte injury and by promoting hepatocyte regeneration. The hIL-10 and hHGF dual gene expression vector has significant potential in the field of liver disease therapeutics and constitutes one of the most promising current strategies for gene therapy.

The intensity of bronchiolar epithelial cell injury caused by an alloimmune response is ameliorated by transbronchial human interleukin-10 gene transfer in a rat model of lung transplantation

The aim of the present study was to determine whether the intensity of bronchiolar epithelial cell injury is ameliorated by transbronchial human IL-10 (hIL-10) gene transfer in a rat model of lung allograft rejection. The left lung was extracted from a donor Brown Norway rat and transbronchially instilled with encoding hIL-10 (IL-10 group) or β-galactosidase (control group). The lung graft was then transplanted into a Lewis rat and harvested on day 6 after transplantation. The allografts were histologically examined and all bronchioles in the slides were assigned one of three grades according to the intensity of epithelial cell loss. The distribution of the grades was significantly different between the two groups, and the epithelial cell injury was significantly improved in the IL-10 group. The present study demonstrated the effect of transbronchial hIL-10 gene transfer on ameliorating bronchiolar epithelial cell injury in a rat model of lung allograft rejection.

Conservation and mutation of viral interleukin-10 gene in gastric carcinomas and nasopharyngeal carcinomas

The Epstein-Barr virus (EBV) BamHI-C fragment rightward reading frame 1 (BCRF1)-coded viral interleukin-10 (vIL-10), exhibits high homology with human interleukin-10 (hIL-10) gene. The protein product vIL-10, which shares some functional properties with hIL-10, primarily mediates immunosuppressive functions. To characterize the variations of the vIL-10 gene and to explore the association between vIL-10 gene variations and EBV associated diseases, the vIL-10 gene was analyzed (using direct sequencing) in 41 cases of EBV-associated gastric carcinoma (EBVaGC), 83 nasopharyngeal carcinoma biopsies, and 40 throat washing samples from healthy donors in Northern China. One silent mutation (c9980a) was observed in the majority of EBVaGC, nasopharyngeal carcinoma and throat washing samples (134/164, 81.7%). Two consensus mutations (V6M and G23S) were identified in the signal peptide region in some nasopharyngeal carcinoma and throat washing isolates. These results indicate that the pattern B95-8 (identical sequence to B95-8) is the dominant type among the EBV isolates from Northern China, while the pattern SPM (mutation in the signal peptide present only in nasopharyngeal carcinoma and throat washing isolates) seems more relevant with the EBV-positive nasopharyngeal and laryngopharyngeal epithelial cells. The conservation of vIL-10, with a few variations, suggests the critical role of the vIL-10 gene for EBV in gaining an advantage over the host's immune system.

Induction of Lymphocyte Apoptosis in Rat Liver Allograft by Adenoviral Gene Transfection of Human Interleukin-10

Background/Aims: Gene therapy can provide a possible avenue in organ transplantation to treat acute allograft rejection. This study was designed to investigate the effect of adenovirus-mediated human IL-10 (hIL-10) gene transfer on the apoptosis of infiltrating lymphocytes and examine the efficacy of hIL-10 gene transfer in combination with subtherapeutic doses of cyclosporine A (CsA) in a rat liver transplantation model. Methods: Inbred male DA and LEW rats were used for liver donors and recipients, respectively. The rats were divided into saline, Ad-lacZ, CsA, Ad-hIL-10 and Ad-hIL-10 + CsA groups. Graft survival, histopathological, enzyme-linked immunosorbent assay, reverse transcriptase-polymerase chain reaction and flow cytometry were performed in liver specimens obtained from different time points after transplantation in the 5 groups. Results: Ad-hIL-10 pretreatment inhibited allograft rejection, prolonged the survival of hepatic allografts, and downregulated the expression of IFN-γ and IL-2 mRNA, with simultaneous upregulation of IL-4 mRNA. In addition, Ad-hIL-10 pretreatment upregulated the expression of Fas mRNA in the isolated graft-infiltrating lymphocytes and induced graft-infiltrating lymphocyte apoptosis. A single subtherapeutic dose of CsA acted synergistically with it. Conclusion: hIL-10 gene therapy induced alloreactive lymphocyte apoptosis via Fas/FasL pathway. hIL-10 gene transfection in combination with subtherapeutic doses of CsA facilitates the long-term survival of liver grafts.

Transbronchial human interleukin-10 gene transfer reduces acute inflammation associated with allograft rejection and intragraft interleukin-2 and tumor necrosis factor-α gene expression in a rat model of lung transplantation

The ability to express genes with potential immunoregulatory capacity could reduce allograft rejection (AR). This study examined the effect of ex vivo lipid-mediated transbronchial human interleukin-10 (hIL-10) gene transfer on AR and the intragraft cytokine profile in a rat model of lung transplantation. Left single lung transplants were performed between a highly histoincompatible combination of inbred rats. The donor left lung was extracted and intrabronchially instilled with a plasmid encoding hIL-10 (IL-10 group) or Escherichia coli beta-galactosidase (control group), mixed with a cationic lipid. At 3 and 6 days after transplantation, the degree of AR was graded histologically (stage 1-4) and several pathologic categories of inflammation were scored on a scale of 0 to 4 according to the percentage of involvement. Intragraft cytokine profile was examined by real-time reverse transcription polymerase chain reaction. The stage of AR (3.1 +/- 0.4 vs 3.8 +/- 0.4) and the pathologic scores for edema (2.3 +/- 0.8 vs 3.2 +/- 0.4), intraalveolar hemorrhage (0.3 +/- 0.5 vs 2.2 +/- 0.8), and necrosis (0.3 +/- 0.5 vs 1.2 +/- 0.4) in the IL-10 group were significantly decreased compared with the control group at Day 6. IL-2 and tumor necrosis factor-alpha messenger RNA expression levels on Day 3 were significantly decreased in the IL-10 group. Ex vivo lipid-mediated transbronchial hIL-10 gene transfer attenuated acute inflammation associated with AR, which was related to decreased levels of proinflammatory cytokine gene expression in a rat model of lung transplantation.

Association of Epstein-Barr virus antibody titers with a human IL-10 promoter polymorphism in Japanese women

BackgroundMultiple sclerosis (MS) risk, over 10-fold higher in Western than in Asian countries, is associated with elevated IgG antibody titers against Epstein-Barr viral capcid antigen (anti-EBVCA IgG titers). Given the 84% homology of the open reading frame BCRF1 of Epstein-Barr virus (EBV) to human interleukin 10 (hIL-10) and the remarkable Caucasian-vs.-Asian population differences in hIL-10 gene promoter polymorphisms, this strong association of MS risk with anti-EB-VCA IgG titers may be explained by the genetic variations in the hIL-10 gene.MethodsWe evaluated anti-EB-VCA IgG titers in association with a single nucleotide polymorphism (SNP) in the promoter of hIL-10 at position -819 (hIL-10 T-819C) in a cross-sectional survey of 241 Japanese. Anti-EB-VCA IgG titer and its elevation (≥ 1:160) were evaluated, stratified by sex and hIL-10 T-819C genotype.ResultsThe cytosine-allele frequencies at hIL-10 T-819C were 32.9% in women and 30.9% in men. These are consistent with the published reports of Japanese and Chinese, but substantially lower than those of Caucasians (> 70%). In women, the proportion with elevated anti-EB-VCA IgG titers (≥ 1:160) increased appreciably from 53.7% in the T/T genotype group to 66.7% in the T/C group and to 83.3% in the C/C group (P-trend = 0.037). The titers did not differ by the hIL-10 T-819C genotype in men.ConclusionAnti-EB-VCA IgG titers may increase with the number of cytosine alleles at hIL-10 T-819C in women. This observed gender specific association in Japanese warrants further investigation, especially in Western populations with high MS risk.

CLONING OF HUMAN INTERLEUKIN-10 GENE AND TRANSGENE EXPRESSION IN RABBIT SYNOVIAL CELLSIN VITRO

In this work, the full-length open reading frame of the human interleukin-10 (hIL-10) gene was amplified through reverse transcription–polymerase chain reaction (RT-PCR), and then PCR products were inserted into pcDNA4/HisMax to construct an eukaryotic expression vector. After optimization by green fluorescent protein (GFP), recombinant hIL-10 genes were transfected and expressed in rabbit synovial cells compounded with liposome in vitro. In cell culture supernatant, rhIL-10 was detected using enzyme-linked immunosorbent assay (ELISA) at time intervals of 12 hours, 24 hours, 48 hours, 72 hours, 7 days, and 14 days. After 12 hours of transfection, ELISA showed that transgene expression of hIL-10 in rabbit synovial cells was elevated; at 72 hours, hIL-10 expression reached its peak value; and then it declined gradually until 7 days, compared with the control. After 14 days, transgene expression ceased. Gene cloning of hIL-10 and its transgene expression in synovial cells therefore gives a basis for the gene therapy of rheumatoid arthritis.

Isografts on subsequent ischemia-reperfusion injury: experiment with rats

To investigate the feasibility of ex vivo adenovirus-mediated gene transfer of human interleukin10 (hIL10) via the pulmonary vein into lung isografts, and to investigate the effect of hIL-10 gene transfer on subsequent ischemia-reperfusion injury (IRI). Fifty-six male SD rats were randomly divided into 4 equal groups: Group D, undergoing left lung isotransplantation with the improved cuff anastomosis technique (the Isografts were transvascularly transfected 5 ml of 5 x 10(9) plaque-forming units/ml adenovec-hIL-10 complex, Group C, with the Isografts transvascularly transfected with blank adenovirus vector Adenovec, Group B, with the Isografts transvascularly transfected with diluent , and Group A, undergoing sham operation. All allografts were preserved for 3 hours at 10 degrees C before transplantation. Four hours after reperfusion blood samples were collected from hr abdominal aorta to undergo blood air analysis. Lung function was evaluated by partial pressure of oxygen (PaO2). Then the rats were killed with their left lung taken out to undergo pathological examination. The graft lung wet-to-dry (W/D) weight ratio was measured. SABC immunohistochemistry was used to detect the expression of hIL-10 in the cytoplasm. ELISA was used to detect the expression of tumor necrosis factor-alpha (TNF-alpha) and interferon-gamma (IFN-gamma). The levels of malonyldialdehyde (MDA), superoxide dismutase (SOD), and myeloperoxidase (MPO) were measured by. Pathological morphologic change was also analyzed. The PaO2 level of Group D was significantly higher than those of Groups B and C (both P < 0.01). The W/D ratio, and levels of MDA and MPO of Group D were significantly lower than those of Groups B and C (both P < 0.01), but the SOD level of Group D was significantly higher than those of Groups B and C (both P < 0.05). The TNF-alpha and IFN-gamma levels of Group D were significantly lower than those of Groups B and C (both P < 0.01). Fewer tissue edema and interstitial inflammation were found in lungs. Of Group D RT-PCR showed hIL-10 expression in the lungs of the rats of Group D, but not in other groups. Ex vivo adenovirus-mediated gene transfer of hIL-10 via the pulmonary vein into the lung isografts is feasible and effective. hIL-10 gene transfer into lung isografts ameliorates subsequent IRI and improves early posttransplant graft function.

Lipid-Mediated Transbronchial Human Interleukin-10 Gene Transfer Decreases Acute Inflammation Associated With Allograft Rejection in a Rat Model of Lung Transplantation

Background Transferring genes with immunoregulatory capacity to transplanted organs has the potential to modify allograft rejection (AR). We examined the effect of ex vivo lipid-mediated transbronchial human interleukin-10 (hIL-10) gene transfer on acute AR in a rat model of lung transplantation. Methods Left single lung transplantations were performed between a highly histoincompatible rat combination: Brown Norway to Lewis. The extracted donor left lung was intrabronchially instilled with a plasmid encoding hIL-10 or Escherichia coli β-galactosidase (control), mixed with a cationic lipid. On day 6 posttransplantation, the degree of AR was graded histologically (stages 1–4) based upon pathological categories of inflammation: perivascular, peribronchial, and peribronchiolar lymphocytic infiltrates, edema, intraalveolar hemorrhage, and necrosis. Results The stage of AR in the IL-10 group (3.1 ± 0.4) was significantly lower than the control group (3.8 ± 0.4). Pathological scores for edema, intraalveolar hemorrhage, and necrosis in the IL-10 group (2.3 ± 0.8, 0.3 ± 0.5, and 0.3 ± 0.5, respectively) were also significantly decreased compared with those in the control group (3.2 ± 0.4, 2.2 ± 0.8, and 1.2 ± 0.4, respectively). Conclusion Ex vivo lipid-mediated transbronchial hIL-10 gene transfer attenuated acute inflammation associated with AR in a rat model of lung transplantation.

Interleukin‐10 Gene Transfer: Prevention of Multiple Organ Injury in a Murine Cecal Ligation and Puncture Model of Sepsis

The aim of this study was to determine the effect of immunoregulatory cytokine interleukin-10 (IL-10) gene therapy on multiple organ injury (MOI) induced by a cecal ligation and puncture (CLP) model of sepsis in mice. Male Balb/c mice subjected to CLP were treated with either an hIL-10-carrying vector or an empty control vector. We assessed the degree of lung, liver, and kidney tissue destruction biochemically by measuring myeloperoxidase (MPO) and malondialdehyde (MDA) activity. Histologic assessments were based on neutrophil infiltration in lung and liver tissue. IL-10 protein expression was examined immunohistochemically, and ultrastructural changes in the liver were studied by transmission electron microscopy. We analyzed the expression of tumor necrosis factor-alpha (TNFalpha) mRNA by reverse transcription polymerase chain reaction 3, 8, and 24 hours after CLP in all organs. Organ damage was significantly reduced by hIL-10 gene transfer, which was associated at the tissue level with reduced MPO activity in the liver, lung, and kidney and decreased leukocyte sequestration and MDA formation in the lung. The liver MDA was not significantly higher in the hIL-10 gene therapy group than in the controls and seemed not to be affected by hIL-10 gene transfer. The reduced portal tract neutrophilic infiltration and preserved ultrastructure of the hepatocytes also showed that tissue function was not impaired. The lung and kidney TNFalpha mRNA expression was suppressed markedly in the hIL-10 gene therapy group, but liver TNFalpha mRNA expression varied over time. These findings showed that IL-10 gene therapy significantly attenuated sepsis-induced MOI.

Electroporation‐mediated interleukin‐10 overexpression in skeletal muscle reduces acute rejection in rat cardiac allografts

Human interleukin 10 (hIL-10) may reduce acute rejection after organ transplantation. Our previous data shows that electroporation-mediated transfer of plasmid DNA to peripheral muscle enhances gene transduction dramatically. This study was designed to investigate the effect of electroporation-mediated overexpression of hIL-10 on acute rejection of cardiac allografts in the rat. The study was designed to evaluate the effect of hIL-10 gene transfer on (a) early rejection pattern and (b) graft survival. Gene transfer was achieved by intramuscular (i.m.) injection into the tibialis anterior muscle of Fischer (F344) male recipients followed by electroporation 24 h prior to transplantation. Heterotopic cardiac transplantation was performed from male Brown Norway rat to F344. Four groups were studied (n = 6). Treated animals in groups B1 and B2 received 2.5 microg of pCIK hIL-10 and control animals in groups A1 and A2 distilled water. Graft function was assessed by daily palpation. Animals from group A1 were sacrificed at the cessation of the heart beat of the graft and those in group B1 were sacrificed at day 7; blood was taken for ELISA measurement of hIL-10 and tissue for myeloperoxidase (MPO) measurement and histological assessment. To evaluate graft survival, groups A2 and B2 were sacrificed at cessation of the heart beat of the graft. Histological examination revealed severe rejection (IIIB-IV) in group A1 in contrast to low to moderate rejection (IA-IIIA) in group B1 (p = 0.02). MPO activity was significantly lower in group B1 compared to group A1 (18 +/- 7 vs. 32 +/- 14 mU/mg protein, p = 0.05). Serum hIL-10 levels were 46 +/- 13 pg/ml in group B1 vs. 0 pg/ml in group A1. At day 7 all heart allografts in the treated groups B1 and B2 were beating, whereas they stopped beating at 5 +/- 2 days in groups A1 and A2 vs. 14 +/- 2 days in group B2 (p = 0.0012). Electroporation-mediated intramuscular overexpression of hIL-10 reduces acute rejection and improves survival of heterotopic heart allografts in rats. This study demonstrates that peripheral overexpression of specific genes in skeletal muscle may reduce acute rejection after whole organ transplantation.

Noninvasive Imaging of ex Vivo Intracoronarily Delivered Nonviral Therapeutic Transgene Expression in Heart

We developed a clinically applicable approach for noninvasive monitoring of reporter-therapeutic linked gene expression in the whole heart of large animals using PET imaging and further validated the efficacy and cardiac adverse effects of reporter-therapeutic linked gene transfer in a rabbit cervical heterotopic functional heart transplant model. Cationic liposome complexed with a vector containing a herpes simplex virus type 1 mutant thymidine kinase (HSV1-sr39tk) as the reporter gene and a recombinant human immunosuppressive cytokine, interleukin-10 (hIL-10), as the therapeutic gene was ex vivo intracoronarily delivered into cardiac allografts before implantation. Long-term HSV1-sr39tk and hIL-10 transgene and protein overexpression associated with myocardial PET reporter probe 9-(4-[18F]fluoro-3-hydroxymethylbutyl)guanine ([18F]FHBG) accumulation was observed in the allografts. The expression of the HSV1-sr39tk gene was significantly correlated with the hIL-10 gene expression and the total myocardial [18F]FHBG accumulation quantified as a percentage of intravenously injected [18F]FHBG dose. A homogeneous distribution of [18F]FHBG accumulation was seen in the whole heart similar to the distribution of [18F]fluorodeoxyglucose, a PET glucose metabolism probe. The immunosuppressive therapeutic efficacy remained the same in allografts treated with reporter-therapeutic linked gene and therapeutic gene only. No cardiac adverse effect was found. Our results demonstrate for the first time that PET reporter-therapeutic linked gene imaging is applicable for noninvasively monitoring ex vivo intracoronarily delivered therapeutic transgene expression in the whole heart.

Adeno-associated virus-mediated human IL-10 gene transfer suppresses the development of experimental autoimmune orchitis

Testicular germ cell-induced autoimmune orchitis is characterized by inflammatory cell infiltration followed by disturbance of spermatogenesis. Experimental autoimmune orchitis (EAO) is an animal model for human immunological male infertility; delayed-type hypersensitivity (DTH) response plays a key role in its induction. Interleukin-10 (IL-10) is a regulatory cytokine that is critical in preventing organ-specific autoimmune inflammation. To determine the effects on EAO of human IL-10 (hIL-10) gene transfer, C3H/He mice immunized by unilateral testicular injury were administered intramuscular (i.m.) injections of adeno-associated viral (AAV) vector-encoding hIL-10 on the day of immunization. Serum hIL-10 was detected beginning at 1 week postinjection, and peaked at 3 weeks. Histological examinations showed a significantly low incidence of orchitis and disturbance of spermatogenesis in AAV hIL-10-treated mice, and the DTH response to autologous testicular cells was significantly suppressed. Immunohistochemical analysis of IFN- and IL-2, T-cell-associated cytokines, in the spleen and testes revealed significantly fewer cytokine-expressing cells after treatment. We conclude that a single i.m. administration of AAV hIL-10 significantly suppresses EAO and hypospermatogenesis by regulating cell-mediated immunity in the testes.

Interleukin-10 Gene Therapy Attenuates Pulmonary Tissue Injury Caused by Mesenteric Ischemia-Reperfusion in a Mouse Model

To investigate the role of interleukin (IL)-10 gene therapy on the reperfusion-induced lung injury, we utilised the technique of liposomal gene delivery before the induction of intestinal ischemia. Plasmid DNA encoding human IL10 (hIL-10) or empy vector was injected intraperitoneally 24 h before the study. Male Balb/c mice randomized into three groups: Sham operated control (n = 12), empty plasmid vector (n = 12), and hIL-10 gene therapy group (n = 12). The ischemia was generated by selective occlusion of superior mesenteric artery for 60 min and followed by reperfusion for 30 min. Lung tissue neutrophil infiltration was determined by myeloperoxidase assay and neutrophil counts. For the determination of lung tissue microvascular permeability, Evans blue dye injection was made and the lung edema was assessed by wet/dry ratio. hIL-10 protein expression was studied by immunostaining and ELISA. We found that pre-ischemic hIL-10 overexpression attenuated dye extravasation, leukocyte sequestration and reduced pulmonary tissue injury compared to the empty vector-injected control. Our study indicates that pre-ischemic hIL-10 overexpression attenuates lung injury caused by intestinal ischemia-reperfusion.