Whole-cell MALDI-TOF MS: A new tool to assess the multifaceted activation of macrophages

► We assessed the ability of whole-cell MALDI-TOF MS to identify activation states of macrophages. ► Macrophage polarisation patterns M1 and M2 were clearly identified by specific fingerprints. ► Whole-cell MALDI-TOF MS allowed the identification of subtypes of M1 and M2 polarisation patterns. ► Macrophages stimulated with various bacteria exhibited specific fingerprints. ► These specific fingerprints may help to study immune cells activation in pathological conditions.