Artificial antigen presenting cells comprising protein l for expanding immune cells for immunotherapy

Abstract

Disclosed herein are methods of expanding immune cells for immunotherapy and/or increasing the purity of a population of CAR T cells using artificial antigen presenting cells (aAPCs) having on their surface Protein L. The disclosed aAPCs can also secrete antibodies that bind molecules of the T cell inhibitory pathway. For example, anti-CD3 scFv on the surface of the aAPCs can bind and activate T cells, while anti-CD28 scFv and 4-1BBL on the surface of the aAPCs can provide dual co-stimulation for the T cells resulting in decreased levels of the markers CD25, TIM3, LAG3, and PD1. For example, blocking PD1/PDL1 ligation can limit suppression that is mediated by the tumor microenvironment. This is a less costly and more efficient alternative to peripheral blood mononuclear cells (PBMCs) and cytokine treatments that result in better quality T cell for adoptive transfer back into patients.