0000000000653362
AUTHOR
Abderaouf Selmi
Abstract LB-130: Combinatorial treatment with intratumoral cytokine mRNAs results in high frequency of tumor rejection and development of anti-tumor immunity across a range of preclinical cancer models
Abstract Cancer immunotherapy localized to the tumor microenvironment holds great potential to promote innate and adaptive immune responses against tumors, while avoiding toxicities related to systemic administration of immuno-modulatory therapeutics. Current strategies for tumor-targeted, gene-based delivery of immune therapies face limitations in the clinic due to suboptimal target expression, anti-vector immunity, potential for unwanted genomic rearrangements and other off target effects. We developed a highly potent synthetic mRNA-based platform for in vivo transfection and sustained intratumoral expression of immuno-modulatory molecules that is capable of inducing immunity to tumor spe…
A liposomal RNA vaccine inducing neoantigen-specific CD4+ T cells augments the antitumor activity of local radiotherapy in mice
Antigen-encoding, lipoplex-formulated RNA (RNA-LPX) enables systemic delivery to lymphoid compartments and selective expression in resident antigen-presenting cells. We report here that the rejection of CT26 tumors, mediated by local radiotherapy (LRT), is further augmented in a CD8+ T cell-dependent manner by an RNA-LPX vaccine that encodes CD4+ T cell-recognized neoantigens (CD4 neoantigen vaccine). Whereas CD8+ T cells induced by LRT alone were primarily directed against the immunodominant gp70 antigen, mice treated with LRT plus the CD4 neoantigen vaccine rejected gp70-negative tumors and were protected from rechallenge with these tumors, indicating a potent poly-antigenic CD8+ T cell r…
Local delivery of mRNA-encoded cytokines promotes antitumor immunity and tumor eradication across multiple preclinical tumor models
Local immunotherapy ideally stimulates immune responses against tumors while avoiding toxicities associated with systemic administration. Current strategies for tumor-targeted, gene-based delivery, however, are limited by adverse effects such as off-targeting or antivector immunity. We investigated the intratumoral administration of saline-formulated messenger (m)RNA encoding four cytokines that were identified as mediators of tumor regression across different tumor models: interleukin-12 (IL-12) single chain, interferon-α (IFN-α), granulocyte-macrophage colony-stimulating factor, and IL-15 sushi. Effective antitumor activity of these cytokines relied on multiple immune cell populations and…
HPV16 RNA-LPX vaccine mediates complete regression of aggressively growing HPV-positive mouse tumors and establishes protective T cell memory
ABSTRACT HPV16 infections are associated with a variety of cancers and there is compelling evidence that the transforming activity of HPV16 critically depends on the expression of the viral oncoproteins E6 and E7. Therapeutic cancer vaccines capable of generating durable and specific immunity against these HPV16 antigens hold great promise to achieve long-term disease control. Here we show in mice that HPV16 E7 RNA-LPX, an intravenously administered cancer vaccine based on immuno-pharmacologically optimized antigen-encoding mRNA, efficiently primes and expands antigen-specific effector and memory CD8+ T cells. HPV-positive TC-1 and C3 tumors of immunized mice are heavily infiltrated with ac…