Single cell gene expression profiling of splenic cells in mice treated with gated CD33-CD123 CARs compared to those with conventional CD123 CAR expression

Single-cell profiling of specific cells in humanized mice treated with gated and conventional CAR-T cells, illustrating the mechanisms of Cytokine Release Syndrome (CRS) and cross-talk between human and mouse cells in animals presenting with CAR-induced CRS symptoms. Humanized SGM3 mice, generated from human CD34+ cells, were evaluated for evidence of engraftment and subsequently inoculated with MOLM-13 AML cells. Following this, a 10-million dose of CAR-T cells (both gated and constitutively expressed) was administered. Mice were monitored weekly, and as symptoms of Cytokine Release Syndrome (CRS) developed and animals reached study endpoints, splenic cells were isolated. These cells were then subjected to single-cell analysis after enrichment for mouse and human CD45+ cells, with the enriched cells added back at a 1:1 ratio.