Two procedures for estimating mean cell volume

Abstract

Mean cell volumes often must be measured during experiments involving cultured cells. For example, knowledge of the cell volume is required to determine the intracellular concentration of any molecule. Also a change in mean cell volume is an indication of cell aging. Although the sizes of cells in culture frequently are distributed widely about the mean, alterations of cell volume in response to most treatments are generally manifest on all cells in the population, and therefore changes in the mean cell volume may be used as a general indication of cell volume changes. Although electronic methods of cell sizing are generally more precise and rapid than manual procedures, not all laboratories have access to the sophisticated instrumentation required; therefore manual procedures still are widely used. Furthermore, since all methods depend upon some absolute calibration standard, manual procedures, if executed with sufficient care, may yield results as accurate as the automated methods. Manual methods involve either: (a) the use of measuring devices such as the ocular micrometer, which depends upon the approximation that the cells are perfect spheres when measured; or (b) determinations of packed-cell volumes, which involve accurate measurements of both the cell pellet volume and the extracellular space.