[The activity of NK and K cells in people vaccinated and revaccinated against plague].

Changes in the activity of NK and K cells in persons immunized against plague have been studied. A decrease in the activity of natural killer cells has been shown to occur. Booster immunization leads to a greater increase in the specific sensitization of lymphocytes, as well as in the antibody level. The observed increase of the activity of killer cells is regarded not as the result of the direct action of live Yersinia pestis cells, but as the result of the immunological changes in the body which they produce.