Effects of temperature and duration of storage on granulocyte adhesion, spreading, and ultrastructure

The effects of storage duration and temperature on granulocyte adhesion, spreading, and ultrastructure were examined. Normal adherence and spreading of granulocytes detected by either phase contrast or scanning electron microscopy was maintained for up to 48 hr when granulocytes were stored at 20 to 24°C. By contrast, storage of granulocytes for 24 hr at 1 to 6°C led to a substantial decrease in granulocyte adherence and spreading. When granulocytes were stored for 24 hr in 1 to 6°C and then shifted to 20 to 24°C for a second 24 hr, granulocytes failed to regain the normal adherence and spreading. The cytoskeleton has been implicated in cell morphology, movement, chemotaxis, and spreading of cells. Transmission electron microscopy of thin sections of whole cells or cytoskeleton preparations revealed a well-organized system of microtubules and microfilaments in granulocytes stored for up to 48 hr at 20 to 24°C. In granulocytes stored at 0 to 6°C that have the decreased adhesion and spreading, there is a paucity of microtubules, and the microfilaments have a disorganized criss-crossed appearance when compared with normal cells. It appears that storage of granulocytes at reduced temperatures is associated with decreased adhesion and spreading, and a concomitant alteration in the cytoskeleton may be responsible for this.