A murine IgG2a monoclonal antibody, termed 6-19, was characterized in terms of its ability to bind to human cell lines and tissues. The hybridoma was selected for antibody binding to multiple human neuroblastoma cultured cell lines but not to peripheral blood mononuclear cells. 6-19 binds to the cell surface of all cultured human nonhematopoietic tumor cell lines tested, to cultured human fibroblasts and endothelial cells, and to nonhematopoietic tumors of many types. It does not bind detectably to any hematopoietic cells, leukemia cells, or lymphomas. In the presence of complement, 6-19 is very cytotoxic to cultured human neuroblastoma cells but not to bone marrow granulocyte-macrophage colony-forming cells. The 6-19 monoclonal antibody may prove useful in the identification or destruction of tumor and stromal cells in bone marrow.
The potential for radioprotection of growing cartilage by the thiophosphate WR2721 was evaluated in weanling rats using single fractions of irradiation. Protection of acute skin toxicity was monitored simultaneously. Single doses of 600, 1200, 1800, or 2400 cGy were administered to the left tibia of CrL:CD(SD)BR female rats in groups of 12. Identically treated groups were injected with 310 mg/kg WR2721 (2/3 the determined LD50/30) in a concentration of 26 mg/ml intraperitoneally 15 min prior to irradiation. Rats untreated or given WR2721 without radiation served as control groups. Radiographs of the irradiated and unirradiated tibiae for each animal were obtained weekly to the date of sacrifice at 80 days following the initial treatment. Skin toxicity was assessed weekly starting on the second week using Moulder's scale (J.E. Moulder, J.J. Fischer, and A. Casey, Radiology 115, 465-470 (1975]. No significant difference in bone growth as measured by tibial lengths for the WR2721-treated or untreated animals was observed. Skin toxicity including moist desquamation occurred in irradiated limbs and was substantially less in rats treated with WR2721. As opposed to previous work with cysteamine, WR2721 as administered had no significant radioprotective effect on tibial growth in weanling rats but substantially reduced the accompanying skin toxicity.
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.