Establishment of a novel cell line, CHO-MK, derived from Chinese hamster ovary tissues for biologics manufacturing.

Chinese hamster ovary (CHO) cells are widely used as a host for producing recombinant therapeutic proteins due to advantages such as human-like post-translational modification, correct protein folding, higher productivity, and a proven track record in biopharmaceutical development. Much effort has been made to improve the process of recombinant protein production, in terms of its yield and productivity, using conventional CHO cell lines. However, to the best of our knowledge, no attempts have been made to acquire new CHO cell lines from Chinese hamster ovary. In this study, we established and characterized a novel CHO cell line, named CHO-MK, derived from freshly isolated Chinese hamster ovary tissues. Some immortalized cell lines were established via sub-culture derived from primary culture, one of which was selected for further development toward a unique expression system design. After adapting serum-free and suspension culture conditions, the resulting cell line exhibited a considerably shorter doubling time (approximately 10 h) than conventional CHO cell lines (approximately 20 h). Model monoclonal antibody (IgG1)-producing cells were generated, and the IgG1 concentration of fed-batch culture reached approximately 5 g/L on day 8 in a 200-L bioreactor. The cell bank of CHO-MK cells was prepared as a new host and assessed for contamination by adventitious agents, with the results indicating that it was free from any such contaminants, including infectious viruses. Taking these findings together, this study showed the potential of CHO-MK cells with a shorter doubling time/process time and enhanced productivity in biologics manufacturing.

Laparoscopic repair of acute small bowel obstruction due to left paraduodenal hernia: A case report.

INTRODUCTION: Paraduodenal hernia is a rare disease but the most common internal hernia. Laparoscopic repair of paraduodenal hernia is feasible and effective because of its minimal invasiveness and aesthetic advantage. PRESENTATION OF CASE: We report a case of a 79 year-old-man who was admitted with a complaint of recurrent left abdominal pain. Computed tomography revealed an encapsulated cluster of jejunum loops in the left upper quadrant, near the ligament of Treitz and at the dorsal side of the inferior mesenteric vein. Emergency laparoscopic surgery was performed. The jejunum loops incarcerated in the hernia sac was reduced. The hernia orifice was closed with interrupted suture. Postoperative period was uneventful and the patient was discharged home on the 7th postoperative day. There has been no recurrence during a follow-up. DISCUSSION: If there is a working space in the abdominal cavity, laparoscopic surgery for paraduodenal hernia leads to patient's early recovery with cosmetic satisfaction. CONCLUSION: Left paraduodenal hernia is a rare cause of small bowel obstruction that should be thought about patient with a history of recurrent abdominal pain. Computed tomography is the standard for a correct diagnosis. Laparoscopic repair as the first surgical option for paraduodenal hernia is feasible despite of technical difficulties.