Vaccination with polyclonal non-tumor-specific IgG has no therapeutic effects on tumorigenic activity of hepatoma cells grafted to rats: experimental and biochemical studies.
BACKGROUND
We studied whether non-tumor-specific polyclonal IgG possesses antitumor effects on hepatoma tumor cells grafted to rats.


METHODS
Hepatoma cells (5 x 10(5)-10(6)) were injected subcutaneously into 6-week-old rats. Some of the rats were vaccinated 2 months later with non-tumor-specific anti-R sheep IgG. Experimental results were checked after additional 2 months.


RESULTS
The tumorigenic effect of grafted hepatoma cells was very high, manifesting itself in the rapid development of subcutaneous tumors in injected rats. Vaccination did not significantly change the number of tumors, their size or spleen weight. A biochemical study showed the main expression of two soluble proteins in high amounts in response to tumorigenesis, with molecular masses of 64 and 53 kDa. HPLC determination revealed that only the blood level of the soluble 53 kDa protein increased significantly with vaccination.


CONCLUSIONS
Vaccination of rats with non-tumor-specific IgG had no tumor-therapeutic effects, despite the concomitant increase in the blood level of the soluble tumor-associated 53 kDa protein. Reaction of this protein should be considered non specific reflecting the host's reaction to stress.
Sandler
B
B
Laboratory of Experimental Oncology, Koret School of Veterinary Medicine, Rehovot, Israel.
Smirnoff
P
P
Gurevich
P
P
Zusman
I
I
D000818:Animals; D000951:Antigens, Neoplasm / Q000097:blood / Q000378:metabolism; D015153:Blotting, Western; D019496:Cancer Vaccines / Q000494:pharmacology / Q000627:therapeutic use*; D006528:Carcinoma, Hepatocellular / Q000473:pathology*; D002851:Chromatography, High Pressure Liquid; D006801:Humans; D007074:Immunoglobulin G / Q000494:pharmacology / Q000627:therapeutic use*; D008297:Male; D009368:Neoplasm Transplantation; D009929:Organ Size / Q000187:drug effects; D051381:Rats; D017207:Rats, Sprague-Dawley; D013154:Spleen / Q000187:drug effects / Q000473:pathology; D013997:Time Factors; D014407:Tumor Cells, Cultured; D016159:Tumor Suppressor Protein p53 / Q000097:blood
D000951:Antigens, Neoplasm; D019496:Cancer Vaccines; D007074:Immunoglobulin G; D016159:Tumor Suppressor Protein p53