An in vitro process of preparing virus-like particles (VLPs) from recombinant papaya mosaic virus coat protein and ssRNA, which allows for large scale production of VLPs in high yields, is provided. Also provided are VLPs comprising ssRNA prepared by the in vitro process. The VLPs can be used as adjuvants and when fused to an antigen, as vaccines. The use of the VLPs for stimulation of the innate immune response is also provided.

Disclosed herein are compositions comprising arenavirus monoclonal antibodies, as well as therapeutic, diagnostic, and preventative methods using the novel antibodies. Preventative methods include preparation of vaccines, as well as factors (e.g. small molecules, peptides) that inhibit Old World arenavirus infectivity, including LASV and LCMV. In some embodiments, the antibodies provide pan-arenavirus protection against a number of arenavirus types and strains. Diagnostic and therapeutic antibodies including neutralizing antibodies for the prevention and treatment of infection by LASV and other arenaviruses are also disclosed, as well as new tools and methods for the design, production, and use of arenavirus monoclonal antibodies, including expression in engineered bacterial- and mammalian-based systems.

The invention relates to arenaviruses for use in the treatment and/or prevention of tumors and also a method for preparing arenaviruses with (improved) tumor-regressive properties.

Disclosed herein are compositions comprising arenavirus monoclonal antibodies, as well as therapeutic, diagnostic, and preventative methods using the novel antibodies. Preventative methods include preparation of vaccines, as well as factors (e.g. small molecules, peptides) that inhibit Old World arenavirus infectivity, including LASV and LCMV. In some embodiments, the antibodies provide pan-arenavirus protection against a number of arenavirus types and strains. Diagnostic and therapeutic antibodies including neutralizing antibodies for the prevention and treatment of infection by LASV and other arenaviruses are also disclosed, as well as new tools and methods for the design, production, and use of arenavirus monoclonal antibodies, including expression in engineered bacterial- and mammalian-based systems.

PD-1 antagonists are disclosed that can be used to reduce the expression or activity of PD-1 in a subject. An immune response specific to an infectious agent or to tumor cells can be enhanced using these PD-1 antagonists in conjunction with an antigen from the infectious agent or tumor. Thus, subjects with infections, such as persistent infections can be treated using PD-1 antagonists. In addition, subjects with tumors can be treated using the PD-1 antagonists. In several examples, subjects can be treated by transplanting a therapeutically effective amount of activated T cells that recognize an antigen of interest and by administering a therapeutically effective amount of a PD-1 antagonist.

Disclosed herein are compositions comprising arenavirus monoclonal antibodies, as well as therapeutic, diagnostic, and preventative methods using the novel antibodies. Preventative methods include preparation of vaccines, as well as factors (e.g. small molecules, peptides) that inhibit Old World arenavirus infectivity, including LASV and LCMV. In some embodiments, the antibodies provide pan-arenavirus protection against a number of arenavirus types and strains. Diagnostic and therapeutic antibodies including neutralizing antibodies for the prevention and treatment of infection by LASV and other arenaviruses are also disclosed, as well as new tools and methods for the design, production, and use of arenavirus monoclonal antibodies, including expression in engineered bacterial- and mammalian-based systems.

The invention relates to arenaviruses for use in the treatment and/or prevention of tumors and also a method for preparing arenaviruses with (improved) tumor-regressive properties.

The invention relates to arenaviruses for use in the treatment and/or prevention of tumors and also a method for preparing arenaviruses with (improved) tumor-regressive properties.

PD-1 antagonists are disclosed that can be used to reduce the expression or activity of PD-1 in a subject. An immune response specific to an infectious agent or to tumor cells can be enhanced using these PD-1 antagonists in conjunction with an antigen from the infectious agent or tumor. Thus, subjects with infections, such as persistent infections can be treated using PD-1 antagonists. In addition, subjects with tumors can be treated using the PD-1 antagonists. In several examples, subjects can be treated by transplanting a therapeutically effective amount of activated T cells that recognize an antigen of interest and by administering a therapeutically effective amount of a PD-1 antagonist.

Disclosed herein are compositions comprising recombinant arenavirus monoclonal antibodies and antigen-binding fragments thereof, as well as therapeutic methods using the antibodies. In some embodiments, the antibodies provide pan-arenavirus protection against a number of arenavirus types and strains.