[\'Institute for Virology and Immunobiology, University of Würzburg, Würzburg, Germany. Electronic address: m.lutz@vim.uni-wuerzburg.de.\', \'Institute for Virology and Immunobiology, University of Würzburg, Würzburg, Germany.\']
Comments on the ambiguity of selected surface markers, signaling pathways and omics profiles hampering the identification of myeloid-derived suppressor cells.