Cell cycle homogeneity in bone marrow samples from different sites: flow cytometric evaluation of multiple samples from sheep.

The distributions of cells in each of the phases of the cell cycle, determined by flow cytometry (FCM), were compared in multiple marrow trephine biopsy samples from 3 sites (both iliac bones and sternum) in 5 sheep. Within any one animal no significant differences could be found between the proportions of cells in the G0/G1, S or G2 + M phases of the cycle from different sites. Differences between animals were detected and these were consistent for any of the sites sampled. We conclude that the proliferative characteristics of marrow cells as determined by FCM in any one animal at one time are comparable at anatomically distinct marrow sites, and that a sample from one site is representative of the whole.