INDUCTION AND ENHANCEMENT OF ANTITUMOR IMMUNITY INVOLVING SINDBIS VIRUS VECTORS EXPRESSING IMMUNE CHECKPOINT PROTEINS

摘要

Provided are polynucleotides and viral vectors, particularly, alphavirus vectors such as Sindbis viral vectors, which encode an immune checkpoint protein, or a ligand binding portion of the checkpoint protein, or an immune checkpoint protein or ligand binding portion thereof fused to one or more immunoglobulin (Ig) domains, e.g., an Ig hinge region and an Ig heavy chain constant domain. Methods of treating a mammalian subject having a cancer or tumor are provided, in which the viral vectors, e.g., a Sindbis virus vector, encoding the immune checkpoint protein, a ligand binding portion thereof, or a checkpoint protein fusion protein as described, are administered to the subject, resulting in an anti-cancer or anti-tumor immune response, significant reduction in tumor growth in the treated subject and increased survivability.