The presently disclosed subject matter provides novel T cell receptors (TCRs) that target an EWSR1/WT1 fusion protein. The presently disclosed subject matter further provides cells comprising such TCRs, and methods of using such cells for treating cancers associated with EWSR1/WT1 fusion protein.

The disclosure provides modified plant viruses designed for delivering a nucleotide of interest into mammalian cells. The modified plant viruses include a plant virus nucleotide sequence (e.g. fragment) that is capable of transfecting a mammalian cell when that mammalian cell expresses a receptor for the modified plant virus. Accordingly, the disclosure also provides receptors for the modified plant viruses as well as methods of using the receptor or the modified plant virus and receptor.

Provided herein are pseudoviruses expressing a SARS-CoV-2 S glycoprotein. Also provided herein are assays that employ the pseudoviruses to evaluate the immunogenicity of a biological sample against a SARS-CoV-2 virus or variant thereof. Also provided herein are methods of evaluating the immunogenicity of a COVID-19 vaccine using the assays.