The Effect of Intravenous Immunoglobulin (IVIG) on Fibrosarcoma Growth in CBA and C57BL/6 Mice

The effect of IVIG in cancer treatment is likely to be mediated by immune cells that regulate tumor progression. Here we studied the effect of IVIG on tumor development in two immunologically contrasting mouse strains, CBA and C57BL/6. We compared the rate of tumor growth, the number of circulating neutrophils and oxidative characteristics of tumor tissue in IVIG-treated and control mice. The animals were inoculated with fibrosarcoma S37 cells, and 14 days after inoculation there was a significant difference between IVIG-treated and control mice: IVIG treatment inhibited tumor growth in CBA mice and stimulated it in C57BL/6. The changes in tumor growth rate were associated with biochemical alterations in tumor tissue. According to the data of biochemical tests, IVIG-treatment influenced activity of tissue myeloperoxidase (neutrophil azurophilic granule enzyme) in CBA and C57BL/6 and of some antioxidant enzymes (glutathione-S-transferase, catalase, glutathione peroxidase) in C57BL/6 mice. Neutrophils content was increased in IVIG-treated CBA mice while in C57BL/6 it remained unaltered and significantly lower than in CBA as was shown by direct count on smears. These results suggest the tight link between the effects of IVIG upon neutrophils and tumor tissue redox balance as a part of regulatory mechanism of tumor growth.