ERBB2 and neoplasm: In contrast to the in vitro data where Lm-spa+ coated with Trastuzumab showed highly significant internalization into 4T1-HER2 cells compared to uncoated Lm-spa+ (Figure 2A), no significant difference of the bacterial counts in liver, spleen or tumor was observed when the mice were treated with antibody-coated or -uncoated Lm-spa+ (Additional file 5).