Manganese potentiation of autologous anti-Meth A tumor vaccines. A developmental study

This study was set up to develop methods for increasing the potency of vaccines against pre-existing transplanted subcutaneous Meth A tumors in Balb/c mice. The vaccines were prepared from particles and surface membrane ghosts from Meth A cells, a transplantable lymphosarcoma originally induced in a Balb/c mouse with methylcholanthrene. It was not possible to increase vaccine potency by conventional methods, but a major increase was achieved by adding manganese and phosphate. Vaccines prepared with these substances stimulated significant numbers of mice to completely reject target tumors transplanted 3 days before immunization. Possible mechanisms for this manganese effect on vaccine potency are discussed in this paper.