Tumor cell vaccines

#The Sequence Listing, which is a part of the present disclosure, is submitted concurrently with the specification as a text file. The name of the text file containing the Sequence Listing is “54907D_Seqlisting.txt”, which was created on Apr. 19, 2022 and is 343,888 bytes in size. The subject matter of the Sequence Listing is incorporated herein in its entirety by reference.

#Cancer is a leading cause of death. Recent breakthroughs in immunotherapy approaches, including checkpoint inhibitors, have significantly advanced the treatment of cancer, but these approaches are neither customizable nor broadly applicable across indications or to all patients within an indication. Furthermore, only a subset of patients are eligible for and respond to these immunotherapy approaches. Therapeutic cancer vaccines have the potential to generate anti-tumor immune responses capable of eliciting clinical responses in cancer patients, but many of these therapies have a single target or are otherwise limited in scope of immunomodulatory targets and/or breadth of antigen specificity. The development of a therapeutic vaccine customized for an indication that targets the heterogeneity of the cells within an individual tumor remains a challenge.

#A vast majority of therapeutic cancer vaccine platforms are inherently limited in the number of antigens that can be targeted in a single formulation. The lack of breadth in these vaccines adversely impacts efficacy and can lead to clinical relapse through a phenomenon called antigen escape, with the appearance of antigen-negative tumor cells. While these approaches may somewhat reduce tumor burden, they do not eliminate antigen-negative tumor cells or cancer stem cells. Harnessing a patient's own immune system to target a wide breadth of antigens could reduce tumor burden as well as prevent recurrence through the antigenic heterogeneity of the immune response. Thus, a need exists for improved whole cell cancer vaccines. Provided herein are methods and compositions that address this need.

#FIGS. 1A and B show reduction of HLA-G mRNA and protein expression in cells stably transduced with shRNA knocking down HLA-G in comparison to controls.

#FIGS. 2A and B show reduction of HLA-G expression increases IFNγ production.

#FIGS. 3A-C show reduction of CD47 expression in the A549 (FIG. 3A), NCI-H460 (FIG. 3B), and NCI-H520 (FIG. 3C) cell lines by zinc-finger nuclease (ZFN)-mediated gene editing.

#Embodiments of the present disclosure provide a platform approach to cancer vaccination that provides both breadth, in terms of the types of cancer amenable to treatment by the compositions, methods, and regimens disclosed, and magnitude, in terms of the immune responses elicited by the compositions, methods, and regimens disclosed.

#In various embodiments of the present disclosure, intradermal injection of an allogenic whole cancer cell vaccine induces a localized inflammatory response recruiting immune cells to the injection site. Without being bound to any theory or mechanism, following administration of the vaccine, antigen presenting cells (APCs) that are present locally in the skin (vaccine microenvironment, VME), such as Langerhans cells (LCs) and dermal dendritic cells (DCs), uptake vaccine cell components by phagocytosis and then migrate through the dermis to a draining lymph node. At the draining lymph node, DCs or LCs that have phagocytized the vaccine cell line components can prime naïve T cells and B cells. Priming of naïve T and B cells initiates an adaptive immune response to tumor associated antigens (TAAs) expressed by the vaccine cell lines. In some embodiments of the present disclosure, the priming occurs in vivo and not in vitro or ex vivo. In embodiments of the vaccine compositions provided herein, the multitude of TAAs expressed by the vaccine cell lines are also expressed a subject's tumor. Expansion of antigen specific T cells at the draining lymph node and the trafficking of these T cells to the tumor microenvironment (TME) can initiate a vaccine-induced anti-tumor response.

#Immunogenicity of an allogenic vaccine can be enhanced through genetic modifications of the cell lines comprising the vaccine composition to introduce TAAs (native/wild-type or designed/mutated as described herein). Immunogenicity of an allogenic vaccine can be further enhanced through genetic modifications of the cell lines comprising the vaccine composition to reduce expression of immunosuppressive factors and/or increase the expression or secretion of immunostimulatory signals. Modulation of these factors can enhance the uptake of vaccine cell components by LCs and DCs in the dermis, facilitate the trafficking of DCs and LCs to the draining lymph node, and enhance effector T cell and B cell priming in the draining lymph node, thereby providing more potent anti-tumor responses.