Discrimination between Macrophage- and NK-Type Tumoricidal Activities via Anti-Asialo GM1 Antibody

Abstract

The usefulness of asialo GM1 a glycolipid surface marker, to define the effector cell types involved in tumor resistance in vitro and in vivo was assessed. Pretreatment of rat effector cells with anti-asialo GM1 antibody plus complement in vitro either abrogated or markedly diminished NK activity; in contrast, macrophage-type cytocidal activity was not diminished by such pretreatment. Similarly, systemic inoculation of anti-asialo GM1 antibody selectively eliminated NK activity, leaving macrophage-type tumoricidal reactivity intact. Finally, such pretreatment did not diminish host resistance in an in vivo tumor model in which the available evidence suggests a critical role for macrophages. The asialo GM1 marker may thus be useful in delimitating the tumoricidal capacity of cells exhibiting NK activity from that mediated by other cell types.

In vivo anti‐tumor activity of combinations of interferon alpha and interleukin‐2 in a murine model. Correlation of efficacy with the induction of cytotoxic cells resembling natural killer cells

“…Since these cytokines have been shown to influence a number of cytotoxic effector cells including NK cells (Djeu et al, 1979;Henney et al, 1981;Brunda and Rosenbaum, 1984;Talmadge et al, 1985;, natural cytotoxic (NC) cells (Lattime et al, 1983), macrophages (Herberman et al, 1982), cytotoxic T cells (Baker et al, 1978) and rIL-2 AK cells (Grimm et al, 1982;, we attempted to determine which cytotoxic effector cell is augmented in mice treatment with rIL-2 and rHuIFN-aA/D. In initial exper-iments, mice were treated in vivo with anti-asialo GMI, which has been reported to inhibit NK but not other cytotoxic cells (Habu et al, 1981;Lattime et al, 1981;Keller et al, 1983). As expected, control mice injected with normal rabbit serum and the 2 cytokines had elevated cytotoxic activity present in both splenic and hepatic effector cell populations (Table V) against YAC-1 and M5076 target cells.…”

Infection of DBA/2 or C3H/HeJ mice by intraperitoneal injection of vaccinia virus elicits activated macrophages, cytolytic and cytostatic for S91-melanoma tumor cells

“…Within the limits of the in vitro assays employed, the complement dependent cytolysis of cells which expressed the asialo-GM1 antigen present in the adherent effector cell population we employed did not affect the level of tumoricidal activity which was measured (Table 4). These experiments suggest that NK cells, which may have been present in the adherent cell population, did not contribute to the tumor cell killing we measured and, in agreement with the conclusions reached by other investigators [23,27,56], our results indicate that the expression of asialo-GM1 antigen on macrophages is not necessarily directly related to expression of macrophage tumoricidal activity.…”

“…and Sci. Co., NY) at 37 °C for 1 h to complete cytolysis of sensitized cells [19,27]. Macrophages treated as described were then tested for their ability to lyse target cells in vitro.…”

Cytomegalovirus Evasion of Innate Immunity by Subversion of the NKR-P1B:Clr-b Missing-Self Axis

“…To demonstrate that this effect is NK dependent, a cohort of rats was pretreated with the NK-depleting antibodies, anti-asialo-GM-1 (Keller et al, 1983) and 3.2.3 mAb (Chambers et al, 1989). Notably, DRCTL virulence was significantly enhanced in NK-depleted animals, such that the differential viral burden between DRCTLinfected animals versus WT-or REV-infected animals was abrogated by in vivo NK depletion (Figures 4B and 4C).…”