Cytotoxic activity and phenotypic analysis of natural killer cells in early normal human pregnancy.
Peripheral blood lymphocytes taken from healthy women planning a pregnancy and then at various intervals up to the 16th week of pregnancy were assayed for natural killer (NK) cell activity against K562 target cells both in a 51Cr-release assay and in a single cell cytotoxicity assay. Results indicated a depression in NK activity from the earliest stages of pregnancy. The target binding capacity of the effector cells remained unimpaired up to 16 weeks, but a significant reduction in the post-binding lytic potential was observed, which parallelled the drop in cytotoxicity as assayed by the 51Cr-release method. The ability of individual effector cells to recycle and kill multiple targets remained essentially unimpaired. Analysis of lymphocyte subpopulations using the monoclonal antibodies anti-Leu-7 and anti-Leu-11b, which recognize NK cell-associated antigens, showed a significant reduction in the proportion of the mature, lytically active Leu-7-11+ cells capable of both binding and lysing K562 target cells. The suggestion that the depression in cytotoxicity may be associated with the reduction in the Leu-7-11+ subpopulation is supported by the high correlation levels observed between the proportion of Leu-7-11+ cells and target cell lysis.
Oncology Research Laboratory, Derby City Hospital, U.K.
H
H
Lee
C D
CD
Gregory
G B
GB
Rees
I V
IV
Scott
P R
PR
Golding
D000911:Antibodies, Monoclonal / Q000276:immunology; D003602:Cytotoxicity, Immunologic; D005260:Female; D006801:Humans; D007694:Killer Cells, Natural / Q000166:cytology / Q000276:immunology*; D010641:Phenotype; D011247:Pregnancy; D011261:Pregnancy Trimester, First; D011262:Pregnancy Trimester, Second
D000911:Antibodies, Monoclonal