TBX1 and neoplasm: Similarly, immunofluorescent detection of brachyury in three PANC-1 pBr clones that expressed brachyury mRNA levels spanning a 3-log range (Fig. 1F, clones A, B and C) showed a proportional staining with MAb 54-1, ratifying the high specificity of the novel MAb 54-1 for detection of brachyury in the context of various tumor cell lines.