Cancer Immune Therapy Edited by G. Stuhler and P. Walden ...

Fig. 16.2 Tumor-protective immune response
elicited by oral DNA vaccine and
boosts of huKS1/4±IL-2 fusion protein. A
control group of female C57BL/6J mice
transgenic for CEA were immunized with
2.5 × 10 5 irradiated MC38-CEA-KSA colon
carcinoma cells on days 0 and 7, and then
challenged after 2 weeks s.c. with a lethal
dose of 2.5 × 10 5 MC38-CEA-KSA cells. Experimental
groups of CEA-transgenic mice
(n = 8) were each immunized by oral gavage
3 times at 2-week intervals with 10 8 attenuated
S. typhimurium harboring either pW-
CEA or pER-CEA plasmids. Control groups
received the attenuated bacteria with either
PBS or the empty vector (pCMV/cyto). Two
16.2 Treatment of Tumor Metastases with Immunocytokines
weeks after the last immunization, all mice
were challenged s.c. in the right front flank
with a lethal dose of 2.5 × 10 5 MC38-KSA-
CEA colon cancer cells. Mice immunized
with pW-CEA were boosted i.v. with five
doses (5 mg each) of huKS1/4±IL-2 fusion
protein (pW-CEA + FP) and an additional
group of naive mice was treated with fusion
protein alone as a control (FP). Animals
were examined daily until the tumor became
palpable, after which its diameter was measured
with microcalipers in two dimensions
every other day. The tumor growth of each
mouse is depicted by a solid line. (*) differences
are statistically significant P