An immunoproteomic approach to characterize the CAR interactome and signalosome.

An immunoproteomic approach to characterize the CAR interactome and signalosome. Sci Signal. 2019 Feb 12;12(568): Authors: Ramello MC, Benzaïd I, Kuenzi BM, Lienlaf-Moreno M, Kandell WM, Santiago DN, Pabón-Saldaña M, Darville L, Fang B, Rix U, Yoder S, Berglund A, Koomen JM, Haura EB, Abate-Daga D Abstract Adoptive transfer of T cells that express a chimeric antigen receptor (CAR) is an approved immunotherapy that may be curative for some hematological cancers. To better understand the therapeutic mechanism of action, we systematically analyzed CAR signaling in human primary T cells by mass spectrometry. When we compared the interactomes and the signaling pathways activated by distinct CAR-T cells that shared the same antigen-binding domain but differed in their intracellular domains and their in vivo antitumor efficacy, we found that only second-generation CARs induced the expression of a constitutively phosphorylated form of CD3ζ that resembled the endogenous species. This phenomenon was independent of the choice of costimulatory domains, or the hinge/transmembrane region. Rather, it was dependent on the size of the intracellular domains. Moreover, the second-generation design was also associated with stronger phosphorylation of downstream secondary messengers, as evidenced by global phosphoproteome analysis. These results suggest that second-generation CARs can activate additional sources of CD3ζ signaling, and this may contr...
Source: Genomics Proteomics ... - Category: Genetics & Stem Cells Authors: Tags: Sci Signal Source Type: research