TP53 and ovarian cancer: In addition, while the original H2 scDb had limited activity against TYK-nu, an ovarian cancer cell line that carries an endogenous TP53R175H mutation and an HLA-A*02:01 allele (1.5 copies of R175H/A2 per cell) (5), the higher-affinity variants all mediated cytotoxicity against TYK-nu without off-target activity against its isogenic control cell line (CRISPR-mediated KO of the TP53 gene) (Figure 2, E and F).