Immunotoxin BAC5-CT treated nasopharyngeal carcinoma / 中国病理生理杂志

ABSTRACT

In this study, immunotoxin (IT) was prepared by conjugating BAC5 and CT with SPDP. The effects of IT on NPC and its mechanisms were explored using double labeled with radioactive nuclides, immunography and electron microscope technique in vivo and in vitro. The specific concentration of BAC5 in the tumor area showed. The radioactivity rate of tumor/nontumor (T/NT) was up to 10.26. IT had cytotoxic effects both on the cultured CNE-2 cell line and tumor multicell spheroides. In vivo, the preliminary result indicated that IT also had a inhibitory action on the nude mice models bearing human NPC (Reported in another article). Under electron microscope, the necrosis and apoptosis of tumor cells were found. The membranes of most tumor cells were found intacted not or corrosined, some of them had the character of apoptosis, including reduce of tumor cells membrane villi, condensation of cytoplasm and pyknosis or cleavage of nuclear. There were many of apoptosis bodies, which were occasionally phagocytosed by tumor cells. The infiltration of immunocytoes in tumor tissue could be seen. The results indicated that BAC5 can specifically combine with NPC cells and BAC5-CT has the inhibitory effect on NPC in vitro and in vivo, mechanism of which may be related to the effects that ‘warhead' CT dissolute the membrane of tumor cells directly, or/and IT promote the infiltration of immunocytoes so as to induce the apoptosis of tumor cell.