For 40 years, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) has been widely used in proteomics and biochemistry. It has been demonstrated in the last decade that MALDI-TOF MS can be used routinely to identify and classify numerous bacterial species or subspecies. We applied MALDI-TOF MS directly to intact mammalian cells, and we found that this method is valuable to identify human circulating cells and cells involved in the immune response including macrophages. We then stimulated human macrophages with cytokines, bacterial products, and a variety of bacteria. We found that MALDI-TOF MS discriminated unstimulated and stimulated macrophages and also detected multifaceted activation of macrophages. We conclude that whole-cell MALDI-TOF MS is an accurate method to identify various cell types and to detect subtle modifications in cell activity and therefore it can be beneficial in clinical practices for a rapid patient classification based on their immune profile.
This is a preview of subscription content, log in to check access.
Springer Nature is developing a new tool to find and evaluate Protocols. Learn more
We thank Nicolas Armstrong, Carine Couderc, Philippe Decloquement, and Christophe Flaudrops for their technical assistance.
Sauget M, Valot B, Bertrand X, Hocquet D (2017) Can MALDI-TOF mass spectrometry reasonably type bacteria? Trends Microbiol 25:447–455CrossRefGoogle Scholar
Seng P, Rolain J-M, Fournier PE et al (2010) MALDI-TOF-mass spectrometry applications in clinical microbiology. Future Microbiol 5:1733–1754CrossRefGoogle Scholar
Armengaud J (2017) Defining diagnostic biomarkers using shotgun proteomics and MALDI-TOF mass spectrometry. Methods Mol Biol 1616:107–120CrossRefGoogle Scholar
Yang H, Chan AL, LaVallo V, Cheng Q (2016) Quantitation of alpha-glucosidase activity using fluorinated carbohydrate array and MALDI-TOF-MS. ACS Appl Mater Interfaces 8:2872–2878CrossRefGoogle Scholar
Ouedraogo R, Flaudrops C, Ben Amara A et al (2010) Global analysis of circulating immune cells by matrix-assisted laser desorption ionization time-of-flight mass spectrometry. PLoS One 5:e13691CrossRefGoogle Scholar
Benoit M, Desnues B, Mege J-L (2008) Macrophage polarization in bacterial infections. J Immunol 181:3733–3739CrossRefGoogle Scholar
Ouedraogo R, Daumas A, Ghigo E et al (2012) Whole-cell MALDI-TOF MS: a new tool to assess the multifaceted activation of macrophages. J Proteome 75:5523–5532CrossRefGoogle Scholar
Meghari S, Bechah Y, Capo C et al (2008) Persistent Coxiella burnetii infection in mice overexpressing IL-10: an efficient model for chronic Q fever pathogenesis. PLoS Pathog 4:e23CrossRefGoogle Scholar
Tantibhedhyangkul W, Prachason T, Waywa D et al (2011) Orientia tsutsugamushi stimulates an original gene expression program in monocytes: relationship with gene expression in patients with scrub typhus. PLoS Negl Trop Dis 5:e1028CrossRefGoogle Scholar
Ryan CG, Clayton E, Griffin WL et al (1988) SNIP, a statistics-sensitive background treatment for the quantitative analysis of PIXE spectra in geoscience applications. Nucl Instr Meth Phys Res Sect B 34:396–402CrossRefGoogle Scholar