Junichiro Arai

Establishment of human endometrial adenocarcinoma cell line containing estradiol-17β and progesterone receptors

The cell line designated HHUA was established from a well-differentiated endometrial adenocarcinoma (grade 1) of a 54-year-old female on December 10, 1980. The cell line grew well without interruption for 22 months and was subcultivated more than 56 times. The cells were spindle or polygonal in shape, formed multilayers, and did not show contact inhibition. The chromosome number varied widely and showed aneuploidy. The modal number was 46 and no marker chromosome was identified. The cells were transplanted into the subcutis of BALB/C nude mice and produced tumors which were interpreted as adenocarcinoma. The cells contained estradiol-17 beta and progesterone receptors. Administration of estradiol-17 beta successfully depleted cytoplasmic estrogen receptors and brought about increased progesterone receptor levels.

L-Proline sensor based on layer-by-layer immobilization of thermostable dye-linked L-proline dehydrogenase and polymerized mediator

Abstract L-Proline sensor has been fabricated through multilayer assembly of recombinant dye-linked L-proline dehydrogenase (L-proDH) originally from hyperthermophilic archaeon (Therococcus profundus) and polymerized mediator, poly(allylamine) ferrocene (PAA-Fc), on a gold electrode by electrostatic layer-by-layer alternate adsorption method. The characteristic redox peaks of ferrocene groups were obvious exhibited in cyclic voltammograms, and both anodic and cathodic peaks increased with PAA-Fc/L-proDH bilayer number which confirmed the formation of a multilayer structure. Further experiments showed that an electrode fabricated in this way catalyzed the oxidation of L-proline. It suggested that polymerized mediator could transfer electrons between electrode surface and immobilized L-proDH. Ampeormetric experiments showed that the current response to L-proline increased with PAA-Fc/L-proDH bilayer number. The stability of the sensor was measured, and it kept a 40% relative response after 30 days storage in buffer under 4 °C.