Comparative staining of gastric adenocarcinoma and diffuse carcinoma with trimeric HLA-E reactive monospecific mAb TFL-033 and β2m-free heavy chain of HLA-E and HLA-I polyreactive mAb MEM-E/02. Please note that intense staining or higher incidence of staining with MEM-E/02 does not imply it is due to intact, trimeric, or dimeric HLA-E but due to the monomeric heavy chain of HLA-I including HLA-E. In adenocarcinoma, MEM-E/02 stained 12 of 30 tissue samples (40%) and the incidence is higher than that of TFL-033 (27%–30%). In diffuse carcinoma, TFL-033 stained 18 of 40 tissue samples (45%). The incidence is higher than that of MEM-E/02 (23%). The node-negative was significantly more positive staining with TFL-033 than with the node-positive. Metastatic cancer included peritoneal (n = 5), liver (n = 3), ovarian (n = 5), and lymph node (n = 27) metastases. With the mAb MEM-E/02, 21 of the 40 metastatic carcinomas stained intensely (53%), higher than that of TFL-033 (38%–40%). With lymph node metastasis, the incidence of staining by TFL-033 was 40%, whereas that of MEM-E/02 is 56.6%. [Source: Sasaki et al.(71)].