PDCD1 and triple-negative breast carcinoma: The use of monoclonal antibodies recognizing programed cell death protein 1 (anti-PD-1 mAbs) has been shown to promote epitope spreading to subdominant epitopes in the context of anti-tumor CD8+ T cell responses [41,46], and certainly suggests a potential role for immune checkpoint inhibitors in SVN peptide microsphere vaccination for triple negative breast cancer immunotherapy.