These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.
Pubmed for Handhelds
PUBMED FOR HANDHELDS
Search MEDLINE/PubMed
Title: Lysis of antigenically unrelated tumor cells mediated by Lyt 2+ splenic T-cells from melphalan-cured MOPC-315 tumor bearers. Author: Barker E, Wise JA, Dray S, Mokyr MB. Journal: Cancer Res; 1989 Sep 15; 49(18):5007-15. PubMed ID: 2788494. Abstract: We have previously shown that mice cured of a large MOPC-315 tumor following low-dose melphalan (L-phenylalanine mustard, L-PAM) therapy can exert, upon challenge with MOPC-315 tumor cells, an antitumor effect against innocent bystander tumor cells present within the same tumor site (Barker, E., and Mokyr, M.B. Cancer Immunol. Immunother., 25: 215-224, 1987). Here we show that T-cells are important for the MOPC-315-induced rejection of MOPC-104E tumor cells present within the same site. To further characterize the innocent bystander killing activity exerted by L-PAM-cured MOPC-315 tumor bearers upon stimulation with MOPC-315 tumor cells, we established the in vitro conditions under which lymphoid cells from L-PAM-cured MOPC-315 tumor bearers can exert an antitumor effect against innocent bystanders. Specifically, we established that spleen cells from mice that just completed the rejection of a large MOPC-315 tumor following low-dose L-PAM therapy can, upon stimulation with MOPC-315 tumor cells, bring about the killing of antigenically unrelated tumor cells in a 12-h 51Cr release assay. The magnitude of lysis of EL4 and WEHI 22.1 tumor cells by MOPC-315 in vitro-immunized (IVI) spleen cells from L-PAM-cured MOPC-315 tumor bearers can be substantially enhanced upon reexposure of the spleen cells to MOPC-315-associated antigens during the 12-h 51Cr release assay. The lysis of innocent bystander tumor cells by these MOPC-315-IVI spleen cells was found to be mediated by T-cells of the Lyt 2 and not the L3T4 phenotype. These Lyt 2+ T-cells did not appear to mediate their lytic activity for innocent bystander tumor cells via effector macrophages, since a drastic reduction in macrophage frequency among the MOPC-315-IVI spleen cells just prior to assessing the lytic activity of the spleen cells did not reduce, but actually enhanced, the magnitude of EL4 lysis. In addition, a Lyt 2+ T-cell clone derived from mice cured of a large MOPC-315 tumor by a low dose of drug was capable, upon stimulation with MOPC-315 tumor cells, of exerting a potent lytic effect against EL4 and WEHI 22.1 tumor cells in the 12-h 51Cr release assay. Thus, Lyt 2+ T-cells independent of effector macrophages are responsible for lysis of innocent bystander tumor cells by MOPC-315-IVI spleen cells from L-PAM-cured MOPC-315 tumor bearers.[Abstract] [Full Text] [Related] [New Search]