Figure 3.

FAP(hF1) UCAR T-cells successfully deplete CAFs and accumulate in TNBC tumor stroma in vivo (A) Schematic of UCAR T-cell treatment and analysis of orthotopic TNBC tumors implanted in NSG mice. (B) Bar graph representing weights of tumor harvested from mice treated with control UT, FAP(hF1) UCAR, FAP(mF3) UCAR or Meso UCAR T-cells as per schematic in (A). Bars show the means ± SEM; P-values determined by Student t test (two-tailed, unpaired), n=2. (C) Flow cytometry plot of human CD45⁺ UCAR T-cell population in orthotopic TNBC tumors harvested from mice treated as indicated. (D) Box and whiskers plot representing quantitation of total number of CD45⁺ cells per gram tumor, calculated using (C). P-values determined by Student t test (two-tailed, unpaired), n=2. (E) Stacked bars plot representing CD4⁺ and CD8⁺ population, as percentage of total human CD45⁺ cells, in orthotopic TNBC tumors from mice treated with indicated UCAR T-cells. Bars show the means ± SEM, n=2. (F) Immunohistochemistry for detection of human CD8⁺ cells in orthotopic TNBC tumors from mice treated with indicated UCAR T-cells. Yellow arrows indicate human CD8 stained cells. (G) Bar graph representing quantitation of (F), each section divided into 4 fields of view. Bars show the means ± SEM; P-values determined by Student t test (two-tailed, unpaired), n=2. (H) Box and whiskers plot representing quantitation of total number of human FAP⁺ cells per gram tumor, as determined by flow cytometry analysis of orthotopic TNBC tumors from mice treated with indicated UCAR T-cells. P-values determined by Student t test (two-tailed, unpaired), n=2. (I) Trichrome staining of orthotopic TNBC tumor sections from mice treated with indicated UCAR T-cells. Collagen network indicated by blue staining. (J) Bar graph representing quantitation of blue stained Collagen area per section (F), measured using ImageJ. Bars show the means ± SEM; P-values determined by Student t test (two-tailed, unpaired), n=2. *P < 0.05; **P < 0.01; ns, not significant.