Bovine endometrium-derived cultured cells are suitable for lipofection.

Bovine-derived cultured cells, including Madin-Darby bovine kidney cells, are used worldwide; however, lipofection tend to result in low transfection efficiency, which has impeded the progress of veterinary research. We performed experiments to confirm the lipofection efficiency of bovine-derived cultured cells, to identify cells that suitable for lipofection. Several bovine tissues (endometrium, testis, ear tissue and foetal muscle) were collected, and primary cultured cells were prepared. Lipofection assay showed that only bovine endometrium (BE)-derived cells could be transfected efficiently (50‒70%). BE cells can be divided into at least two types of cell populations (BE-1 and BE-2). The BE-1 cells, which were suitable for lipofection, were obtained by passages at short intervals and were negative for cytokeratin- and positive for vimentin-expression; the BE-2 cells did not have these characteristics and were not suitable for lipofection. Furthermore, the BE-1 cells and artificially immortalised cells of BE-1, iBE-1 cells, were utilised in a reporter assay requiring the introduction of multiple DNAs. Endometrial tissues can be collected from living cows, and BE-1 cells can be obtained easily by controlling passaging timing. The production of BE-1 cells and sharing the methods required to prepare them will contribute to the development of veterinary research.

Establishment and characterization of a new malignant peritoneal mesothelioma cell line, KOG-1, from the ascitic fluid of a patient with pemetrexed chemotherapy resistance.

Malignant peritoneal mesothelioma (MPeM) is a rare and aggressive form of malignant mesothelioma. Sufficient biological tools for studying the functional characteristics of this cancer have not been developed. Therefore, in this study, a novel human cancer cell line, KOG-1, was established from ascites fluids isolated from a 39-year-old Japanese woman with pemetrexed-resistant MPeM. Cells were dendritic or linear immediately after thawing, showed a jigsaw puzzle-like and spindle arrangement during growth, and formed monolayers without contact inhibition in two-dimensional (2D) culture. The population doubling time was 13.7 h. Karyotypic and molecular genetic analyses showed that chromosome numbers ranged from 62 to 142, with a peak of 73 with complicated copy number alterations. No germline BAP1 pathogenic variant was detected. Cells expressed various tumor markers of mesothelioma, such as calretinin, podoplanin, and Wilms tumor 1 (WT-1). Drug sensitivity and resistance testing with a set of 36 drugs using 2D and three-dimensional (3D) culture models demonstrated that KOG-1 cells showed high and low sensitivity to pemetrexed under 2D and 3D culture conditions, respectively, whereas control ovarian cancer cell lines showed low sensitivity to pemetrexed under both culture conditions. This newly established cell line will be a valuable biological resource to expand the feasibility of functional studies as well as drug testing for potential therapeutic purposes in MPeM.