[Hsp70-H22 tumor antigen peptide complex activated dendritic cell in the induction of antitumor immunity].
OBJECTIVE
To investigate the feasibility of reduction in tumor antigen peptide dose by dendritic cell (DC)-presenting so as to elucidate the characteristics of modifying DC by heat shock protein (Hsp70) and antigen peptide.


METHODS
Antigen peptide bound to Hsp70 was used to modify DC in vitro. The metabolism of the modified DC and the cytokine secreted thereby was determined. Then the activation of lymphocytes by the modified DC and Hsp70-H22 peptide was tested. The cytotoxicity of the activated lymphocytes to H22 tumor cells and the inhibition of tumor in mice by DC injection and Hsp70-H22 peptide was tested.


RESULTS
0.15 micro g of H22 peptide bound to Hsp70 could mature 2 x 10(5) DC. 4 x 10(3) matured DC could activate 2 x 10(6) lymphocytes. The same amount of lymphocyte could be activated to produce similar cytotoxicity to tumor cells by either DC modified by 0.003 micro g of peptides bound with Hsp70 or by direct stimulation with 0.15 micro g of peptides bound to Hsp70. The dose of peptide could be reduced to 1/50 if the modified DC injection was used instead of direct Hsp70-peptide injection. Peptide from the normal hepatocytes, if bound to Hsp70, could not mature DC, nor could it activate lymphocytes through DC.


CONCLUSIONS
The dose of Hsp70-H22 peptides can be reduced significantly by DC-presenting to activate lymphocytes. Peptides from normal cells, being unable to activate the lymphocytes by either Hsp70-presenting or DC-presenting, have little to offer in the induction of autoimmunity.
Huang
Bo
B
Department of Biochemistry and Molecular Biology, Tongji Medical College, Central China Science and Technology University, Wuhan 430030, China.
Feng
Zuohua
Z
Zhang
Guimei
G
Li
Dong
D
Wang
Hongtao
H
D000818:Animals; D000951:Antigens, Neoplasm / Q000276:immunology*; D003713:Dendritic Cells / Q000276:immunology*; D004195:Disease Models, Animal; D018840:HSP70 Heat-Shock Proteins / Q000737:chemistry / Q000276:immunology* / Q000627:therapeutic use; D007109:Immunity; D008213:Lymphocyte Activation; D051379:Mice; D008807:Mice, Inbred BALB C; D009368:Neoplasm Transplantation; D009374:Neoplasms, Experimental / Q000517:prevention & control; D010455:Peptides / Q000737:chemistry / Q000276:immunology / Q000627:therapeutic use; D014407:Tumor Cells, Cultured
D000951:Antigens, Neoplasm; D018840:HSP70 Heat-Shock Proteins; D010455:Peptides