Standardized flow cytometry assay for identificacion of human monocytic heterogeneity and LRP1 expression in monocyte subpopulations

To present a novel flow cytometry assay for determination of human blood monocyte subpopulations, i.e., the CD14++CD16-, CD14++CD16+, and CD14+CD16++ monocytes, and LRP1 expression in each monocyte subpopulation.
Conclusion:
-LRP1 is mainly expressed in monocytes, which allows a clear separation of these cells by flow cytometry from other leukocyte subsets using a SSC vs. LRP1 plot. -Percentages of monocyte subpopulations measured by the LRP1 monocytic strategy were significantly comparable with those obtained with the HLA-DR procedure. -LRP1 is differentially detected by flow cytometry in monocyte subpopulations, being higher in CD14++-monocytes (classical and intermediate) than in CD14+-monocytes (nonclassical) of healthy subjects. -The total variation yield by the measurement of LRP1 and monocyte subpopulations [(aCV%2 + bCV%2)½] was not higher than 20%. To minimize pre-analytical variance as much as possible, specimens were collected at approximately the same time of the day (between 08:00 and 09:30 a.m.). Specimens of each individual were analyzed in duplicate.