Single-cell transcriptomics identifies multiple pathways underlying antitumor function of TCR- and CD8αβ-engineered human CD4 T cells.

Transgenic coexpression of a class I-restricted tumor antigen-specific T cell receptor (TCR) and CD8αβ (TCR8) redirects antigen specificity of CD4 T cells. Reinforcement of biophysical properties and early TCR signaling explain how redirected CD4 T cells recognize target cells, but the transcriptional basis for their acquired antitumor function remains elusive. We, therefore, interrogated redirected human CD4 and CD8 T cells by single-cell RNA sequencing and characterized them experimentally in bulk and single-cell assays and a mouse xenograft model.

CAR T-cells that target acute B-lineage leukemia irrespective of CD19 expression.

Chimeric antigen receptor (CAR) T-cells targeting CD19 demonstrate remarkable efficacy in treating B-lineage acute lymphoblastic leukemia (BL-ALL), yet up to 39% of treated patients relapse with CD19(-) disease. We report that CD19(-) escape is associated with downregulation, but preservation, of targetable expression of CD20 and CD22. Accordingly, we reasoned that broadening the spectrum of CD19CAR T-cells to include both CD20 and CD22 would enable them to target CD19(-) escape BL-ALL while preserving their upfront efficacy.

TIMING 2.0: high-throughput single-cell profiling of dynamic cell-cell interactions by time-lapse imaging microscopy in nanowell grids.

Motivation: Automated profiling of cell-cell interactions from high-throughput time-lapse imaging microscopy data of cells in nanowell grids (TIMING) has led to fundamental insights into cell-cell interactions in immunotherapy. This application note aims to enable widespread adoption of TIMING by (i) enabling the computations to occur on a desktop computer with a graphical processing unit instead of a server; (ii) enabling image acquisition and analysis to occur in the laboratory avoiding network data transfers to/from a server and (iii) providing a comprehensive graphical user interface.

Results: On a desktop computer, TIMING 2.

Galiximab signals B-NHL cells and inhibits the activities of NF-κB-induced YY1- and snail-resistant factors: mechanism of sensitization to apoptosis by chemoimmunotherapeutic drugs.

Galiximab (anti-CD80 monoclonal antibody) is a primatized (human IgG1 constant regions and cynomologus macaque variable regions) monoclonal antibody that is currently in clinical trials. Galiximab inhibits tumor cell proliferation through possibly cell signaling-mediated effects. Thus, we hypothesized that galiximab may signal the tumor cells and modify intracellular survival/antiapoptotic pathways such as the NF-κB pathway.

Mcl-1 and YY1 inhibition and induction of DR5 by the BH3-mimetic Obatoclax (GX15-070) contribute in the sensitization of B-NHL cells to TRAIL apoptosis.

The pan Bcl-2 family antagonist Obatoclax (GX15-070), currently in clinical trials, was shown to sensitize TRAIL-resistant tumors to TRAIL-mediated apoptosis via the release of Bak and Bim from Mcl-1 or Bcl-2/Bcl-XL complexes or by the activation of Bax, though other mechanisms were not examined. Herein, we hypothesize that Obatoclax-mediated sensitization to TRAIL apoptosis may also result from alterations of the apoptotic pathways. The TRAIL-resistant B-cell line Ramos was used as a model for investigation.

A potential mechanism of rituximab-induced inhibition of tumor growth through its sensitization to tumor necrosis factor-related apoptosis-inducing ligand-expressing host cytotoxic cells.

Rituximab (anti-CD20 mAb) mediates antibody-dependent cell-mediated cytotoxicity (ADCC), complement-dependent cytotoxicity (CDC), and apoptosis in B-NHL cells. The contribution of other host-mediated cytotoxic effects has not been examined. The expression of death-inducing ligands (e.