Gravity effect on lymphocyte deformation through cell shape change

Abstract

The effects on human cells (lymphocyte) immersed in a culture liquid under microgravity environment has been investigated. The study was based on the numerical simulation of the Morphology of human cells affected by the time dependent variation of gravity acceleration ranging from 10(-3) to 2 g(o) (g(o) = 9.81 m/s2) in 15 s. Both the free floating cells and the cells which came into contact with the upper and lower inclined walls imposed by the time-dependent reduced gravity acceleration were considered in this study. The results show that, when the gravity acceleration increased, the cell morphology changed from spherical to horizontally elongated ellipsoid for both the free floating cells and the stationary cells on the lower inclined wall while the cell morphology varied from spherical to vertically-elongated ellipsoid for the cells hanging on the upper inclined wall. A test of the deformation of human cells exposed to the variation of gravity levels, carried out in the KC-135 free fall aircraft, show that the results of experimental observations agree exactly with the theoretical model computation described in this paper. These results will be useful for study of the behavior and morphology of cells in space.