Therapeutic ISCOMATRIX adjuvant vaccine elicits effective anti-tumor immunity in the TRAMP-C1 mouse model of prostate cancer

Barr, AM; Silva, A; Prato, S; Belz, GT; Maraskovsky, E; Baz Morelli, A

Author(s): Barr, AM; Silva, A; Prato, S; Belz, GT; Maraskovsky, E; Baz Morelli, A;
Details: Publication Year 2020-05-09,Volume 69,Issue #10,Page 1959-1972
Journal Title: Cancer Immunology Immunotherapy
Publication Type: Journal Article
Abstract: Cancer vaccine development has proven challenging with the exception of some virally induced cancers for which prophylactic vaccines exist. Currently, there is only one FDA approved vaccine for the treatment of prostate cancer and as such prostate cancer continues to present a significant unmet medical need. In this study, we examine the effectiveness of a therapeutic cancer vaccine that combines the ISCOMATRIX adjuvant (ISCOMATRIX) with the Toll-like receptor 3 agonist, polyinosinic-polycytidylic acid (Poly I:C), and Flt3L, FMS-like tyrosine kinase 3 ligand. We employed the TRAMP-C1 (transgenic adenocarcinoma of the mouse prostate) model of prostate cancer and the self-protein mPAP (prostatic acid phosphatase) as the tumor antigen. ISCOMATRIX-mPAP-Poly I:C-Flt3L was delivered in a therapeutic prime-boost regime that was consistently able to achieve complete tumor regression in 60% of animals treated and these tumor-free animals were protected upon rechallenge. Investigations into the underlying immunological mechanisms contributing to the effectiveness of this vaccine identified that both innate and adaptive responses are elicited and required. NK cells, CD4(+) T cells and interferon-gamma were all found to be critical for tumor control while tumor infiltrating CD8(+) T cells became disabled by an immunosuppressive microenvironment. There is potential for broader application of this cancer vaccine, as we have been able to demonstrate effectiveness in two additional cancer models; melanoma (B16-OVA) and a model of B cell lymphoma (Emicro-myc-GFP-OVA).
Publisher: Springer
Research Division(s): Immunology
PubMed ID: 32388678
Link To PubMed Central Version: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7223769/
Publisher's Version: https://doi.org/10.1007/s00262-020-02597-6
NHMRC Grants: NHMRC/1135898,
Terms of Use/Rights Notice: Refer to copyright notice on published article.

Creation Date: 2020-05-18 11:15:13

Last Modified: 2020-10-17 02:55:29