An experimental therapeutic cancer vaccine induced immune system responses that led to significant tumour regression in mice, according to investigators from the National Institute of Allergy and Infectious Diseases (NIAID), part of the National Institutes of Health.
The researchers found that intravenous (IV) administration of the vaccine SNAPvax boosted the number of cytotoxic T cells capable of infiltrating and attacking tumour cells and engaged the innate immune system by inducing type I interferon.
The innate immune response modified the tumour microenvironment, counteracting suppressive forces that otherwise would tamp down T-cell action. Modification of the tumour microenvironment was not seen in mice that received the vaccine via subcutaneous administration.
Dubbed “vax-innate” by the scientific team, the approach enables and enhances T-cell immunity by overcoming tumour-induced immunosuppressive activity.
The researchers say the candidate vaccine might also be given intravenously to people who have already received tumour-specific T cells as a therapy. It also could improve tumour control by increasing the number of T cells and altering the tumor microenvironment to make them function better.
SNAPvax was designed by Robert Seder and colleagues at the NIAID Vaccine Research Center (VRC) with collaborators from Vaccitech North America.
Vaccitech has announced plans to advance the SNAPvax platform for use in treating human papilloma virus-associated cancer in 2023.
Read the full paper: Systemic vaccination induces CD8+ T cells and remodels the tumor microenvironment.
