In this experiment, the murine melanoma cell B16-F10 oncolysates transfected by recombinant vaccinia viruses encoding human IL-2(IL-2VBO) were used as vaccine. When the tumor-bearing mice were treated by following injection of IL-2VBO into tumor site, the tumor growth was inhibited and the survival time prolonged. The PBL from IL-2VBO treated mice showed higher cytotoxicity to the wild type B16-F10 but not to YAC-1 cells than that from control groups. The results showed the active specific immunity was induced by the IL-2VBO. On accout of its stronger immuogenicity and some advantages in preparing and storing, the IL-2VBO might be used as a kind of effective vaccine in the cancer active specific immunotherapy.

Escherichia coli cytosine deaminase ( CD) gene was transfected into murine B16F10 melanoma cells by recombinant adenovirus AdCD in vitro . The tumor cells infected with AdCD were more sensitive to 5-fluorocytosine (5FC) than cells infected with a control adenovirus AdLacZ. The supernatant from B16F10 cells treated with AdCD/5FC was transferred to uninfected cells, and we found that only 6. 25 % of the supernatant could significantly inhibit the growth of wild type B16F10 cells. When AdCD was directly injected into established subcutaneous B16F10 tumors in mice followed by intraperitoneal injection of 5FC for 10 days, a significant reduction in tumor size and prolongation of survival period were observed. These studies not only explored the cytotoxic effects of AdCD/5FC on B16F10 melanoma cells in vitro and in vivo but also elucidated the mechanisms of its bvstander effect.

We previously showed that adenvirus-mediated lymphotactin (Ltn) gene transfer in vivo could improve the an-titumor efficacy of cytosine deaminase (CD) gene therapy significantly. In the precent study, we investigated the im-munological mechanisms involved in the enhanced antitumor efficacy. Upregulation of CD80 and CD54 on murine CT26 colon carcinoma cells was observed after combined transfection with adenovirus encoding CD (AdCD) and adenovirus encoding murine Ltn ( AdLtn) followed by administration of 5-PC in vitro. IL-2 and IFN-? level secreted by splenocytes increased significantly after the combination therapy. In vivo depletion analysis showed that both CD4~+ and CD8~+ T cells participated in the antitumor effect of the host with CD8~+ T cells being the main T cell subset responsible for the enhanced antitumor immune response. These data suggested that increased irnmunogenicity and efficient induction of antitumor immunity of the host might contribute to the enhanced antitumor effects of the combined Ltn and CD suicide therapy.

Platelet activating factor (PAF) is a biologically active membrane phospholipid mediator. In this study we investigated the effects of PAF on the lymphocyte proliferation, production of IL-2, natural killer cytotoxic factor (NKCF) and colony stimulating factor (CSF) by BALB/c mice splenocytes in vitro. The results showed that PAF inhibited lymphocyte proliferation at concentrations of 10-10~ 10-7 mol/L. CTLL-2, YAC-1 and munne bone marrow cells were used for the assays of IL-2, NKCF and CSF, respectively. Production of IL-2, NKCF and CSF from ConA stimulated murine splenocytes was significantly inhibited by PAF at 10-7 mol/L. Inhibition of spleen cells proliferation and secretion may play an important role in the pathological effects of PAF.

Adenoviruses harboring E. coli cytosine deaminase gene (AdCD) were used to transfect murine FBL-3 ery-throleukemia cells in vitro. FBL3 cells infected with AdCD were more sensitive to 5-fluorocytosine (5-FC) than cells infected with a control adenovirus AdLacZ. Further study indicated that this combination therapy (AdCD and 5-FC) killed tumor cells by inducing apoptosis of FBL-3 cells. The supematants from FBL-3 cells treated with AdCD/5-Fc were transferred on the culture system of uninfected (wild - type) FBL-3 cells, the result indicated that only 6.25% of the supernatant could induce significant cytotoxicity on wild type FBL3 cells. The results demonoustrated that bystander effect plays an important role in AdCD-mediated cytotoxicities. Direct injection of AdCD into established subcutaneous FBL3 tumor in mice followed by daily intraperitoneal injection of 5-FC for 10 days was found to inhibit tumor growth significant-

Antitumor effect of combined transfer of suicide gene and cytokine gene was evaluated in the present study. Adenoviruses expressing E. coli. cytosine deaminase (AdCD) and adenoviruses expressing murine interleukin 2 (AdTL2) were used for the treatment of tumor-bearing mice. The mice were inoculated s. c. with FBL-3 leukemia cells and 3 days later received intratumoral injection of AdCD in the presence or absence of AdIL2 followed by intraperitoneal 5-fluorocytosine (5FC) administration. The results demonstrated that tumor-bearing mice treated with AdCD/5FC in combination with AdTL2 showed more .potent inhibition of tumor growth and survived much longer as compared with mice treated with AdCD/5FC, AdEL2, AdlacZ/5FC or PBS. It was illustrated that the tumor mass showed obvious necrosis and inflammatory cell infiltration, and more CD4+ and CD8+ T cells infiltrated into the tumor after combined therapy. The splenic NK and CTL activities increased significantly in mice after combined transfer of CD gene and EH gene. Our results demonstrated that combined transfer of suicide gene and IL-2 gene could inhibit the growth of established tumor in mice significantly and induce antitumor immunity of the host efficiently.

Adenovirus harboring E. coli. cytosine deaminase gene (AdCD) and adenovirus encoding with lymphotactin gene (AdLtn) were used for gene therapy in vivo. BALB/c mice were inoculated subcutaneously with CT26 colon adeno-carcinoma cells and 3 days later received combined injection of AdCD and/or AdLtn followed by continuous injection with 5-fluorocytosine(5-FC) 300mg/kg. The results demonstrated that mice received combined therapy developed tumors most slowly and survived longest when compared with mice treated with AdCD/5-FC, AdLtn, AdlacZ/5-FC or PBS. To further explain the immunological mechanism of the antitumor effects by the combined therapy, we found that combined treatment with suicide gene and Ltn gene therapy achieved maximal cytotoxic effects of nature killer cells and specific cy-totoxic T lymphocytes. FACS analysis of the tumor mass demonstrated that AdCD/5-FC in combination with AdLtn therapy increased the expression of H-2K~d and B7-1 expression on tumor cells. The CD4~+ and CD8~+ cells infiltrated in the tumor mass after combined therapy were significantly increased when measured by FACS analysis. Our results demonstrated that combined transfer of suicide gene and lymphotactin gene induce nonspecific and specific antitumor immunity of the host and elicit more potent antitumor effect.

Gene therapy is rapidly emerging as a powerful therapeutic strategy for a wide range of neurodegenerative disorders, including Alzheimer's disease (AD), Parkinson's disease (PD) and Huntington's disease (HD). Some early clinical trials have failed to achieve satisfactory therapeutic effects. Efforts to enhance effectiveness are now concentrating on three major fields: identification of new vectors, novel therapeutic targets, and reliable of delivery routes for transgenes. These approaches are being assessed closely in preclinical and clinical trials, which may ultimately provide powerful treatments for patients. Here, we discuss advances and challenges of gene therapy for neurodegenerative disorders, highlighting promising technologies, targets, and future prospects.

The Hedgehog (HH) signaling pathway plays important roles in gastrointestinal carcinogenesis and the gastrointestinal tumor microenvironment (TME). Aberrant HH signaling activation may accelerate the growth of gastrointestinal tumors and lead to tumor immune tolerance and drug resistance. The interaction between HH signaling and the TME is intimately involved in these processes, for example, tumor growth, tumor immune tolerance, inflammation, and drug resistance. Evidence indicates that inflammatory factors in the TME, such as interleukin 6 (IL-6) and interferon-

Diabetic nephropathy (DN) is considered the primary causes of end-stage renal disease (ESRD) and is related to abnormal glycolipid metabolism, hemodynamic abnormalities, oxidative stress and chronic inflammation. Antagonism of vascular endothelial growth factor B (VEGF-B) could efficiently ameliorate DN by reducing renal lipotoxicity. However, this pharmacological strategy is far from satisfactory, as it ignores numerous pathogenic factors, including anomalous reactive oxygen species (ROS) generation and inflammatory responses. We found that the upregulation of VEGF-B and downregulation of interleukin-22 (IL-22) among DN patients were significantly associated with the progression of DN. Thus, we hypothesized that a combination of a VEGF-B antibody and IL-22 could protect against DN not only by regulating glycolipid metabolism but also by reducing the accumulation of inflammation and ROS. To meet these challenges, a novel anti-VEGFB/IL22 fusion protein was developed, and its therapeutic effects on DN were further studied. We found that the anti-VEGFB/IL22 fusion protein reduced renal lipid accumulation by inhibiting the expression of fatty acid transport proteins and ameliorated inflammatory responses