Production and Quality Control of Adenoviral Vectors for Clinical Trials

The importance of recombinant adenoviral vectors for the development of gene therapy and prophylactic and therapeutic vaccines has led to efforts for process development of large scale production of clinically safe adenoviral vectors. First of all, cell lines producing replication incompetent adenoviral vectors required for clinical application have been developed and the concept of banking and characterization of cell lines and adenoviral vectors has been established. In order to meet the need of amount of adenoviral vectors for clinical trials, various large scale suspension culture methods using serum-free media have been developed along with development of large scale purification methods using chromatography instead of cesium chloride method. In addition, methods for the quality control of adenoviral vectors have been established and applied for the clinical lots.

Purification of Protein Expressed from Three Different Regions of Norovirus (NoV)

Norovirus (NoV), which belongs to the family Caliciviridae, is one of the major causes of nonbacterial acute gastroenteritis in the world. In this study, we purified proteins from the epitope region of norovirus for development of the rapid diagnosis system using polyclonal antibodies. As antigens, parts of the ORF (open reading frame) 2, ORF2-P domain, ORF2-Epi, and ORF3 regions were selected and their expressions were induced. The antigenicity of the purified proteins was identified by Western blotting. Each of the purified proteins was injected into mice for the production of novel antibodies and after 3 months of immunization, sera from the mice were obtained. The polyclonal antibody titer was tested by enzyme-linked immunosorbent assay (ELISA) and antibody against ORF2-Epi showed the highest titer. Those polyclonal antibodies can be used in further immunoassay for the rapid detection of NoVs from food and clinical specimens.

Immunohistochemical Expression of P-Glycoprotein in Gynecologic Malignancies / 대한부인종양콜포스코피학회잡지

The expression of P-glycoprotein in gynecological tissues was studied by immunohistochemical staining methods. Aspects of study included the expression of P-glycoprotein in different tissues throughout the clinical treatment regimen, the relationship between the expression of P-glycoprotein and the degree of pathologic malignancy, and the expression of P-glycoprotein in cancerous tissue before and after chemotherapy. Studies were based on patients who were admitted to the Department of Obstetrics and Gynecology of Chungnam National University Hospital from January 1988 to December 1993. Tissue samples collected prior to chemotherapy included 34 ovarian cancers, 73 cervical cancers, and 11 endometrial cancers. Pre and post-chemotherapy tissue samples included 11 ovarian cancers and 15 cervical cancers. Normal tissue samples included 12 from the ovaries, 15 from the cervix, and 10 from the endometrium. RESULTS ARE AS FOLLOWS:1. p-glycoprotein was mainly found in the cytoplasm of both normal tissue cells and cells of tissues prior to chemotherapy. After chemotherapy it was found more intensely in the cell membrane than in the cytoplasm. 2. For normal tissue, p-glycoprotein was found in 25% of ovarian tissues, 33.3% of uterine cervical tissues, and 40.0% of endometrial tissues. 3. For cancerous tissues prior to chemotherapy, p-glycoprotein was found in 45.5% of ovarian cancer cases, 47.9% of uterine cervical cancer cases, and 45.5% of endometrial cancer cases. There was no statistically meaningful difference in these rates in cancerous versus normal tissues. 4. The expression of P-glycoprotein in cancerous tissues prior to chemotherapy was not related to histologic type. 5. For ovarian cancer tissue, p-glycoprotien was expressed in 45.5% of cases prior to chemotherapy, and 54.4% of cases subsequent to chemotherapy. For uterine cervical cancer tissue, p-glycoprotein expression rates before and after chemotherapy was 46.7% and 60.0% respectively and there was a statistically meaningful difference(p<0.05). 6. There was no relationship between P-glycoprotein expression in cancer tissues after chermotherapy and the presence of cisplatin in chemotherapeutic drugs. 7. For uterine cervical cancer tissues prior to chemotherapy, there was no relationship between the degree histologic differentiation and the expression of P-glycoprotein. 8. For cancerous tissues there was no relationship between clinical stage and the expression of P-glycoprotein. In conclusion, the expression of P-glycoprotein was identified in the tissues before the drug exposure. However, there was no relationship between the expression of P-glycoprotein and hlstologic type, clinical stage, and effectiveness of chemotherapy, This may be related to P-glycoprotein inducing a cellular resistance to chemotherapeutic agents, although the importance of this resistance is thought to be small. Further studies of P-glycoprotein are needed to delineate its role in cellular anticancer drug resistance.

Combination Treatment of Interferon alpha-2a plus 13-cis Retinoic Acid and Radiation Therapy in Cervical Cancer / 대한부인종양콜포스코피학회잡지

Cervical cancer is one of the leading causes of cancer death worldwide. A major research in cervical cancer is focused on the development of new active agents arid agents to potentiate radiotherapy effect in locally advanced diseases. Both interferons and retinolds are known to possess antiproliferative, differentiate, and immunomodulatory properties, but they probably exert these effects through separate molecular mechanisms. The rationale for adding interferon and retinoid to standard radiotherapy is based on the independent major activity of combination of these biological agents and the additive and synergistic effects of these agents with radiation in mammalian cells in tissue culture. This study was undertaken to assess the clinical response and toxicity of the combination regimens of interferon alpha-2a(IFN alpha-2a), 13-cis-retinoic acid(13-cRA) with radiotherapy from Nov. 1994 to Nov. 1995 at Chungnam National University Hospital. Twenty seven patients with locally advanced cervical carcinoma enrolled in this study were evaluated. Thirteen of these patients who were previously untreated(study group) were treated with 13-cRA(1mg/kg) orally and recombinant human IFN alpha-2a(6 million units) subcutaneously daily for one week and then, on the second week, IFN alpha-2a was administered with the same dosage every other day and 13-cRA was administered 0.5mg /kg/oral for 8 weeks combined with the standard radiotherapy. Eleven of these patients(control group) who were previously untreated were treated only with standard radiotherapy Three patients who had recurrence after initial treatment were treated with IFN alpha-2a and 13-cRA with the same amount for 8 weeks. THE RESULS WERE AS FOLLOWS; 1. Preliminary result of the response rate of IFN alpha-2a, 13-cRA with radiotherapy was 92.3%(complete response: 61.5%, partial response: 30.8%) and that of radiotherapy only was 91.0%(complete response: 45.5%,partial response: 45.5%). 2. Reduced tumor volume was 95.64+/-80.03cm(3) in the study group and 25.28+/-35.82cm(3) in the control group. There was a significant difference in the reduced tumor volume between the study and the control group(p<0.05). 3. The major toxicity of IFN alpha-2a, 13-cRA with radiothrapy was cheilitis(92.3%), fever(84.5%), general myalgia(53.8%) and conjunctivitis(53.8%). 4. The treatment with IFN alpha-2a and 13-cRA in recurrent ceivical cancer showed no effect. As a result, these data suggest that systemic IFN alpha-2a, 13-cRA with radiotherapy is highly active and is a well tolerable therapy for locally advanced cervical cancer.