Cell cycle distribution in‐vivo of mononuclear blood cells of renal allograft recipients

Abstract In 47 healthy blood donors (controls) and 29 renal allograft recipients (patients) the relative contents of RNA and DNA of peripheral blood mononuclear (PBM) cell populations were estimated from the intensities of green and red fluorescences emitted by complexes that form with DNA and RNA, respectively, after staining the cells with the metachromatic dye, acridine orange. Based on the correlated DNA and RNA estimates for large numbers of cells, the percentages and the relative RNA contents of cells in particular compartments of the cell cycle were determined. PBM cell populations of controls contained < 0.5% proliferating (SG2M) cells with highly variable relative RNA contents. Among controls, neither percentages nor relative RNA contents of SG2M‐cells were correlated with percentages or relative RNA contents of G1‐cells with an RNA content 2 (2SD) or 3 (3SD) standard deviations above the mean of the entire GO/1‐cell population. Unlike controls, PBM cell populations of patients contained significantly higher percentages of SG2M‐cells which were significantly correlated with the relative coefficients of variation (rCV) of the F530 histograms of GO/1‐cells; the rCV represents the ratio of a patient's CV to a control's CV. Moreover, significant statistical correlations existed between percentages and relative RNA contents of 2SD‐, 3SD‐, SG2M‐and GO/1‐cells, suggesting a well‐orchestrated progression of cells through the cell cycle. Different pairs of correlated parameters characterized clinically stable, acutely rejecting, and infected patients. Finally, the data of this pilot project suggest that two features of GO/1‐cells, namely the rCV and the mean relative RNA content may carry the information necessary to predict the cell cycle distribution of PBM cells of stable, rejecting, or infected renal allograft recipients.