The CD8+ natural killer (NK) subpopulation has recently been identified as a fast and reliable biodosimetric indicator within human peripheral blood mononuclear cells (PBMC) in vitro. In irradiated and subsequently cultivated PBMC, a decrease of the relative number of intact CD3-CD8+ lymphocytes 16 and 48 h after treatment has allowed for estimating the received dose in the range of 0 - 10 Gy and lethal/sublethal dose discrimination, respectively. Here we show that suitable biodosimeters can also be found in the peripheral blood B-cell compartment. Multiparameter flow cytometric analysis of irradiated and subsequently cultivated human PBMC revealed that both the CD27+ and CD21- B-cell subpopulations can be used as biodosimeters and the CD19+CD27+ lymphocytes have proved useful for retrospective determination of the received dose in the range of 0 - 6 Gy. In addition, several CD19+ lymphocyte subsets characterized by co-expression of CD21, CD27 and CD38 have been shown to bear biodosimetric potential, too. However, when important parameters like the original size within the CD19+ compartment, its radiation-induced changes and data variation had been taken into account, the CD27+ subpopulation proved superior to the other B-cell subpopulations and subsets. It appears that, in the dose range of 0 - 6 Gy, the relative decrease of CD27+ B lymphocytes provides more sensitive and reliable data than that of CD8+ NK-cells due mainly to lower data variation. In contrast to CD27+ B-cells, the proportions of CD27+ subpopulations of T-cells were not affected by irradiation. We have also proposed a simple experimental protocol based on full blood cultivation and three-color CD27/CD3/CD19 immuno-phenotyping as a time-saving and inexpensive approach for practical biodosimetric evaluations on simple, three-to-four color flow cytometers., Z. Řeháková, J. Šinkora, M. Vlková, D. Vokurková, J. Österreicher, J. Vávrová, D. Driák., and Obsahuje bibliografii a bibliografické odkazy
Prenatal development of cord blood monocytes and tissue macrophages was studied in pig foetuses by immunophenotyping and functional assays. The function of peripheral blood monocytes was compared in germ- free and conventional piglets. First macrophages were identified by electron microscopy in foetal liver on the 25th day of gestation. Monoclonal antibodies against porcine CD45 and SWC3 antigens were used for flow cytometric identification of myelomonocytic cells in cell suspensions prepared from the yolk sac, foetal liver, spleen and cord blood. Leukocytes expressing the common myelomonocytic antigen SWC3 were found in all organs studied since the earliest stages of development. Opsonized zymosan ingestion assay was used to determine the phagocytic capacity of foetal mononuclear phagocytes isolated from cord blood, liver and spleen. In the foetal liver, avid phagocytosis of apoptic cells had been found to occur before cells were able to ingest zymosan in vitro. The first cells capable of ingesting zymosan particles were found on the 40th day of gestation in umbilical blood and 17 days later in foetal spleen and liver. Their relative proportion increased with age. Cord blood monocytes and peripheral blood monocytes in germ-free piglets had low oxidatory burst activity as shown by iodonitrophenyl tetrazolium reduction assay. A remarkable increase of oxidatory burst activity was observed in conventional piglets, probably due to activation of immune mechanisms by the microflora colonizing gastrointestinal tract.