[Purification of hsp70 and its immunoprotective effect against mouse hepatoma].
OBJECTIVE
To purify hsp70 protein and observe its anti-tumor effect on mouse H22 hepatoma.


METHODS
Cytosolic hsp70 protein of heat treated H22 cells was purified successively by chromatographic procedures, including DEAE 52-cellulose, ConA-sepharose 4B and ADP-argarose chromatography. The molecular weight and the identity of the purified hsp70 protein were confirmed by SDS-PAGE and Western blot. Tumorigenicity of H22 hepatoma was examined in purified hsp70-treated C3H mice.


RESULTS
A sharp stained protein band with a molecular weight of about 70 kD was obtained and shown to be hsp70 as confirmed by Western blot. In C3H mice challenged with H22 hepatoma, tumor developed in 6 of 6 mice while in hsp70 pretreated mice, none of the 6 H22 challenged mice developed tumor. Nevertheless, C57BL/6 mice pretreated with hsp70 or RPMI 1640 all developed tumor upon challenge with EL-4 lymphoma.


CONCLUSIONS
The results suggest that the immunoprotective effect of hsp70 protein is due not to hsp70 per se, but rather to the specific antigenic peptides it carries.
Wu
W
W
Liver Cancer Institute, Zhongshan Hospital, Shanghai Medical University, Shanghai 200032, China.
Liu
K
K
Gao
Y
Y
D000818:Animals; D000970:Antineoplastic Agents / Q000302:isolation & purification* / Q000627:therapeutic use; D006528:Carcinoma, Hepatocellular / Q000517:prevention & control; D004195:Disease Models, Animal; D018840:HSP70 Heat-Shock Proteins / Q000302:isolation & purification* / Q000627:therapeutic use; D008114:Liver Neoplasms, Experimental / Q000517:prevention & control; D051379:Mice; D008809:Mice, Inbred C3H; D008810:Mice, Inbred C57BL; D009368:Neoplasm Transplantation; D012685:Sepharose / Q000031:analogs & derivatives*; D014407:Tumor Cells, Cultured; D023041:Xenograft Model Antitumor Assays
D000970:Antineoplastic Agents; D018840:HSP70 Heat-Shock Proteins; C028326:concanavalin A-sepharose; D012685:Sepharose