Flow cytometric analysis of some activation/proliferation markers on human thymocytes and their correlation with cell proliferation.

We immunophenotyped cells from ten human thymuses with emphasis on expression of the CD38 and CD71 antigens. These antigens play role in activation cells and increased expression of them was observed in some leukemia. Simultaneously, certain attention has also been devoted to some further activation markers, e.g. CD25, CD26 and HLA-DR. The classification of leukemia is based on comparison of normal and pathological cells. The study of expression of CD38, CD71 and other markers on thymocytes simultaneously with DNA analysis can be useful for answer if expression of CD38 and CD71 on pathologic cells is a sign of their proliferative ability, a part of immature phenotype in some leukemia, or it is a case of aberrant immunophenotype. In our study, 94% thymocytes were CD38+ and only 16% were CD71+. From our immunophenotypic results including MESF (molecules of equivalent soluble fluorochrome) values and analysis of the cell cycle, the conclusion could be drawn that antigen CD71 can participate in regulation of thymocyte development and presence of both -CD38 and CD71 on pathologic cells will be in all probability the case of aberrant phenotype. We observed a clear correlation of the percentage and MESF values of CD71-positive cells with the cell proliferation only after in vitro thymocytes stimulation with PHA and IL-2. In summary, a strong parallelism was observed regarding the positive relationship between the proliferative rate (assessed by the number of S-phase cells) of stimulated thymocytes and the quantitative (% and MESF) values of some markers - CD71, CD25, CD26 and HLA-DR and negative one with CD38 marker values.

Immunomodulatory activity of amphiphilic antimicrobials on mouse macrophages.

A quaternary ammonium salt (1-methyldodecyl)-trimethylammonium iodide, a structurally analogous amine oxide (1-methyldodecyl)-dimethylamine-N-oxide and the amine oxide lacking long alkyl chain trimethylamine-N-oxide were tested for their immunomodulatory activity. Inbred mice strain C57/BL6 were pretreated for 7 days by the compounds under study. The activity of elicited peritoneal macrophages was also tested. Both compounds have a long alkyl chain. In concentrations of 10(-6) M there was a significant increase of the phagocytic, candidacidal and lysozyme activities of the cells. We also observed a suppressed peroxidase activity. The colicidal activity of both the peritoneal and spleen cells were not affected. The amine oxide lacking the long alkyl chain has the same effect at high concentration. A similarity between the effects of the amphiphilic compounds on the macrophages and their antimicrobial efficacy elicits the conclusion that both activities are caused by their ability to interact with the cell membranes.