Preventive vaccination of mice with human melanoma cells injected into subcutaneously encapsulated polyacrylamide gel

S.E. Severin**, N.S. Sergeeva*, I.K. Sviridova*, E. Yu. Moskaleva**, V.A. Kirsanova*, I.A. Rodina*, A.V. Rodina**, V.I. Frolov*

* Moscow Herzen Research Oncological Institute, Moscow, Russia

** Moscow Research Institute of Medical Ecology, Moscow, Russia

e-mail: sergsev@aha.ru

High degree of homology of melanocytic human and mouse antigens and species specificity are the main features in favour of xenogenic vaccination. In our studies, the vaccinating material was injected subcutaneously into preliminarily implanted encapsulated polyacrylamide gel (PAAG). The use of this approach affords effective protection of the xenogenic cells from rapid elimination by NK-cells.

The goal of our study was elaboration of a method for xenogenic vaccination using a model of mouse melanoma B-16.

Human melanoma cells (SKMEL-1: 0.25E106 –4,0E106 cells/animal) were implanted into the encapsulated gel. Six weeks thereafter, the melanoma B-16 cells (0.062E106-1.5E106 cells/animal) were inoculated, after which the cytotoxic activity of mouse splenocytes against B-16 cells was examined.

It was found that the vaccinating (2E106 cells/animal) and reinoculating (0.5E106 cells/animal) doses of B-16 inhibited cell growth by more than 70% for 2.0-2.5 weeks. When B-16 were used in the reinoculating dose (0.062E106 cells/animal), the vaccination prevented the growth of melanoma cells in 72% of animals. The cytotoxic activity of splenocytes increased (by 50%) beginning with week 2 following the vaccination and remained at this level for over 12 weeks.

Preventive xenogenic vaccination into encapsulated PAAG proved to be highly effective in model studies with mouse melanoma B-16.