Global analysis of circulating immune cells by matrix-assisted laser desorption ionization time-of-flight mass spectrometry.
BACKGROUND
MALDI-TOF mass spectrometry is currently used in microbiological diagnosis to characterize bacterial populations. Our aim was to determine whether this technique could be applied to intact eukaryotic cells, and in particular, to cells involved in the immune response.


RESULTS
A comparison of frozen monocytes, T lymphocytes and polymorphonuclear leukocytes revealed specific peak profiles. We also found that twenty cell types had specific profiles, permitting the establishment of a cell database. The circulating immune cells, namely monocytes, T lymphocytes and polymorphonuclear cells, were distinct from tissue immune cells such as monocyte-derived macrophages and dendritic cells. In addition, MALDI-TOF mass spectrometry was valuable to easily identify the signatures of monocytes and T lymphocytes in peripheral mononuclear cells.


CONCLUSIONS
This method was rapid and easy to perform, and unlike flow cytometry, it did not require any additional components such as specific antibodies. The MALDI-TOF mass spectrometry approach could be extended to analyze the cell composition of tissues and the activation state of immune cells.
Unité de Recherche sur les Maladies Infectieuses Tropicales et Emergentes, Centre National de la Recherche Scientifique-Institut de Recherche pour le Développement Unité Mixte de Recherche 6236, Université de la Méditerranée, Faculté de Médecine, Marseille, France.
Richard
R
Ouedraogo
Christophe
C
Flaudrops
Amira
A
Ben Amara
Christian
C
Capo
Didier
D
Raoult
Jean-Louis
JL
Mege
D000818:Animals; D007962:Leukocytes / Q000145:classification* / Q000276:immunology; D051379:Mice; D008810:Mice, Inbred C57BL; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods*