Mouse normal lymphoid cells were analysed as to their ability to perform in three cytolytic systems: Ability to act as 'natural killer', NK, cells against a NK sensitive tumour target, YAC; as effector cells against IgG-coated 815 cells, or to function as effector cells against IgG-coated CRBC. NK activity and ADCC against the IgG-coated P815 cells were found to vary in parallel as affected by age, organ distribution and genotype of the effector cells. On the other hand, ADCC against CRBC was largely carried out by effector cells distinct from those functioning as NK cells or in ADCC against P815. Temperature pretreatment schedules at 37 degrees C showed both NK cells and ADCC ability against P815 to be highly sensitive on contrast to ADCC against CRBC. Likewise, inoculation of Corynebacterium parvum intraperitoneally will lead to reduction in ADCC ability against CRBC but increase in ADCC against P815 and NK activity. Blocking experiments using 'cold' inhibitor cells in the cytolytic assays indicated that NK cells and effector cells against IgG-coated P815 cells are the very same cells. We thus conclude that NK cells in the mouse also have the ability to express K cell activity against IgG-coated tumour target cells. In fact, our data suggest that the NK cells may be the only cell type in the mouse equipped with cytolytic potential for antibody-coated murine nucleated cells
We have analyzed the impact of in vivo administration of Corynebacterium parvum on the mouse immune system against murine tumors, using the natural cytotoxic ability against tumors of normal mouse lymphoid cells as a baseline. A striking difference was found depending on the route of administration. Intravenous inoculation of bacteria would result in a significant decrease or sometimes complete abolition of natural cytotoxicity toward tumor cells of the spleen cells of treated mice. On the other hand, the intraperitoneal route of administration resulted in a dramatic increase in cytolytic ability of the peritoneal exudate cells. Both routes of treatment had the most significant impacts on the local cell population (IV = spleen, IP = peritoneal exudate cells) with only minor effects on other cell populations. Analysis of the spleen cell population from IV-treated mice did also demonstrate a significant reduction in the T lymphocyte function, but in contrast to the natural cytotoxicity this could be corrected for by the removal of suppressor cells of an adherent nature. The lytic cells induced in the peritoneal exudate by the Corynebacterium parvum bacteria were all found to be natural killer, NK, cells with no significant activity found amongst macrophages using short-term cytolytic assays.
Peritoneal exudate cells taken from mice 3 days after intraperitoneal treatment with Corynebacterium parvum (Cp) have been shown to kill specifically certain tumour targets in vitro. We have analysed in detail such Cp-induced cytotoxic cells as to their cellular characteristics, considering the fact that size and charge characteristics of cellular subgroups are useful markers in describing their representative characteristics. We could thus show that the cytolytic cell could not be classified as a macrophage. They behaved, in every manner analysed, exactly as the previously defined natural killer cells found in the lymphoid organs of normal mice.
Mice were treated with a heterologous anti-IgM serum to obtain B-cell-deprived mice. Spleen cells from normal and B-cell-deprived mice were tested in three different cytolytic systems: natural killer cells (NK); antibody-dependent cell-mediated cytolysis (ADCC) against an NK-sensitive tumour, P815; and ADCC against chicken erythrocytes. The impact of administration of an interferon-inducing NK enhancing agent, Tilorone, was also investigated. Whereas the cell population from B-cell-deprived mice was significantly suppressed in antibody-producing cells, the capacity to function in NK or ADCC was largely unimpaired both before and after administration of Tilorone. Our results would imply that mature B cells play no significant role in either the maturation of the NK cells or the expression of their cytolytic ability. Furthermore, effector cells for both NK and ADCC against antibody-coated tumour target cells were found to be distinct from those functioning in ADCC against chicken erythrocytes.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.