ABSTRACT
The natural killer(NK) cell activity of mononuclear cells (MNC) from peripheral blood (PB) and synovial fluid (SF) of 40 rheumatoid arthritis(RA) patients was investigated by employing 51-chromium-(51Cr) release microcytotoxicity and single cell cytotoxicity assays against K562 target cells. It has been revealed that SF-MNC from RA patients showed a significantly lower NK activity than PB-MNC from the same patients and this might be due to an impaired target binding capacity of the effector cells and not due to a deficiency of active NK cells.
Subject(s)
Adolescent , Adult , Aged , Female , Humans , Male , Arthritis, Rheumatoid/immunology , Chromium Radioisotopes , Comparative Study , Cytotoxicity Tests, Immunologic/methods , Cytotoxicity, Immunologic , In Vitro Techniques , Killer Cells, Natural/immunology , Middle Aged , Synovial Fluid/immunologyABSTRACT
The suceptibilities of ascitic S180 cells to NK cell-mediated binding and killing during their development in vivo were studied at a single cell level, usingsingle cell cytotoxic and binding assaies. The results showed that the NK binding and killing suceptibilities of ascitic S180 cells changed sequentialy during their growth in vivo, the kinetics of which had an appearence of reversed S with both NK binding and killingsuceptibilities being the highest at the fifth day and the lowest at the second day and the tenth day after inoculation of the tumors. However, the changes were seen to be similar when the tumors were inoculated in either adult(6-7-week-old) or yaung(3-week-old) mice, or in different strains of adult mice. Analysis at a single cell level revealed that the change in the NK suceptibilitg of the tumor cells at different growth stages were concomitant with the changes in the number of the tumor target cells capable of being bound by NK cells as shown with an NK-target binding assay, which was consistant to the flactuation of the capability on which the tumor target cells could bind more than one NK cell. Our results indicate the NK-suceptibility of ascitic S180 cells changes uring their growth in vivo, due to the changes of the ratio of NK-suceptible and-nonsuceptible target cells in the tumor cells at different growth stages. The possible cause(s) for the changes is discussed here.