In vivo trafficking of <sup>89</sup>Zr-oxine-labeled CAR T cells was evaluated in 2 murine xenograft tumor models: glioblastoma brain tumors with intracranially delivered IL13Rα2-targeted CAR T cells, and subcutaneous prostate tumors with intravenously delivered prostate stem cell antigen (PSCA)-targeted CAR T cells.
With respect to prostate cancer, prostatic acid phosphatase, prostate‑specific antigen, prostate‑specific membrane antigen (PSMA), prostate stem cell antigen, T‑cell receptor γ alternate reading frame protein, transient receptor potential‑p8 and six‑transmembrane epithelial antigen of the prostate 1 are among the identified target antigens for prostate tumors.
We also demonstrated that immunization of mice with the bivalent vaccine (Ad<sub>5</sub>-PSA+PSCA) inhibited the growth of established prostate tumors.
The in vivo tumor growth study showed that immunization of mice with Ad5-PSA/PSCA vaccine induced strong antitumor immunity when challenged with mouse prostate tumor cell lines (RM11) expressing human PSA (RM11/PSA).
Mouse PSCA (mPsca) shares 65% homology with human PSCA at the nucleotide and amino acid levels. mRNA expression of mSteap and mPsca is largely prostate-specific and highly detected in primary prostate tumors and metastases of TRAMP mice.