Abstract
An approach to stimulating an immune response against tumors is to transduce tumor cells with bacterial genes, which represent a "danger signal" and can induce a wide immune response. Mycobacterium tuberculosis genes and their encoded proteins play a pivotal role in linking innate and cell-mediated adaptive immunity and represent ideal candidates as immune adjuvants for tumor vaccines. The efficacy of a cancer vaccine, obtained by transduction of a mammary tumor cell line with the M. tuberculosis Ag38 gene, was investigated in female mice transgenically expressing the rat HER-2/neu proto-oncogene. These mice spontaneously develop stochastic mammary tumors after a long latency period. The onset of spontaneous mammary tumors was significantly delayed in mice vaccinated with Ag38-transduced cells but not in mice vaccinated with nontransduced cells as compared with untreated mice. Protection from spontaneous tumor development was increased when mice were vaccinated with the mycobacterium gene-transduced vaccine plus a systemic administration of interleukin 12 (IL-12) at a low dose. Mice vaccinated with nontransduced cells plus IL-12 developed tumors, with only a slight delay in tumor appearance as compared with the control group. Lymphocytes obtained from lymph nodes of mice vaccinated with transduced cells secreted high levels of IFN-γ. CD3 +CD8 + spleen cells derived from these mice responded to the tumor with IFN-γ production. These data indicate the efficacy of a short-term protocol of vaccinations exploiting the adjuvant potency of a M. tuberculosis gene and low doses of IL-12 in a model of stochastic development of mammary tumors. This adjuvant approach may represent a promising immunotherapeutic strategy for cancer immunization.
Original language | English |
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Pages (from-to) | 3777-3781 |
Number of pages | 5 |
Journal | Cancer Research |
Volume | 60 |
Issue number | 14 |
Publication status | Published - Jul 15 2000 |
ASJC Scopus subject areas
- Cancer Research
- Oncology