A scanning electron microscope study of the sequential changes in morphology occuring in human fibroblasts placed in suspension culture.

Trypsinized human embryonic fibroblasts placed in suspension culture demonstrated a distinct sequence of changes in the topography of the underlying surface and in the nature and distribution of processes. After 4 h the typical cell showed a rippled surface from which protruded a few small 'blebs' and several microvilli. This appearance was very similar to that displayed by confluent monolayer cultures of fibroblasts. The fibroblasts survived in suspension for at least 8 h and, as their topography appeared to revert to normal, suspended cells may prove a reasonable system for studying early alterations in the surface appearance and metabolism of fibroblasts following the addition of various agents, including viruses, provided they are allowed 4 h to recover from the trypsin.