Ann: Phase 1 onCARlytics Trial Advances to Combination Arm, page-108

Quick theoretical question...Solid tumours have long been an issue when it comes to CAR-T capabilities. I understand the use of cf33 to induce CD19 expression on solid tumour cell lines then further treating with CD19 targeting therapies. However in melanoma for example, HER2-CAR T targetting cells have very limited effect against HER2+ Tu in murine. A lot of people have put this down to matter of a more difficult and intricate tumour microenvironment? So does that mean cf33 just induces an extreme expression of target antigen (cd19) and this how it can get an upperhand on a cell line that may express 100% but not at this extreme amount? TIA, GLTA