Characteristic Feature of Lymphoblastic Cell Growth in Rotory Cell Culture System under Microgravity

• Main Authors: Wu Pei-Fen, 吳佩芬
• Other Authors: 周崇龍
• Format: Others
• Language: zh-TW
• Published: 2000
• Online Access: http://ndltd.ncl.edu.tw/handle/85945561356694247623

碩士 === 國防醫學院 === 航太醫學研究所 === 88 === The cellular reaction during early activation under the circumstance of microgravity is prone to be affected by alteration in gravity. The gravitational change was sensed and transformed to intracellular biochemical reactive mechanisms. Many possible factors might participate in the intracellular gravisensing mechanism but remained uninvestigated. It would be helpful to clarify the contributing factors of gravisensing mechanism if we can detect the time-course of cellular reactions under gravitational change. Our experiment mainly intended to demonstrate the relation between early cellular activation and gravitational change via determining the time-course of protein kinase C (PKC) translocation and human lymphoblastic (Jurkat cells) activation under microgravity. We developed a cell culture model in the rotary cell culture system (RCCS) mimicking microgravity to maintain the cells in low shearing and continuously suspending. The cell count and survival difference could be analyzed in different gravity by means of cellular physiologic monitoring. The translocation of PKC among different activation time and fluctuation of intracellular amount was recorded through conjugation with Ⅸ phorbol ester 12, 13-dibutyrate (PDBu) and PKC activation. Thus, we can describe the possible factors related to gravitational change in early cellular activation and, furthermore, understand the intracellular gravisensing mechanisms. The results showed that the increase in the cell count of experimental group from 48hrs of incubation was markedly smaller than that of control group. Also the cell survival rates of experimental group at time point of 36 to 96 hours were significantly lower (P<0.01). The results were identical when performing in the outer space. It can be concluded that the simulated microgravity for incubation constructed in our laboratory can appropriately reflect the real environment of outer space. In the quantification of PKC while comparing Jurkat cell membrane10 and 60 min after administration of PDBu; meanwhile, it delineated that PKC has translocated to cell membrane 60 min after PDBu administration. In addition, the concentration PKC in cell membrane increased as well as incubation time and reached peak concentration in 120 hours; so was contrary to the cytoplasm PKC. As a consequence, it clearly demonstrated the translocation of PKC from cytoplasm to cell membrane.