PTPRC and neoplasm: Tumors of mice that received Reo&CD3-bsAbs + αTGF-β demonstrated loss of TRP1 expression in the majority of CD45− cells, similar to tumors of mice treated with Reo&CD3-bsAb (Fig. 5F), a phenomenon previously described in mice with successful tumor regressions upon Reo&CD3-bsAb treatment (8).