Comparative proteomics study of the THP-1 cells engulfing Coxiella burnetti

Two dimension electrophoresis was used to compare the changes of protein expression spectrum in human monocytes THP-1 cells engulfing Coxiella burnetti and those of THP-1 cells without engulfment of this organism. By means of matrix-assisted laser desorption/ionization-time of flight-mass spectrometry (MALDI-TOF-MS), 6 protein spots which showed remarkable changes in THP-1 cells engulfing C.burnetti were identified. The data obtained from the peptide mass finger-printing were searched against the NCBInr database by using the Program Mascot, and 8 protein spots in gel were identified as ORP, 150 kDa, gp96, hsp96, hnRNPs, gelsolin, zyxin and IMP dehydrogenase. These proteins were mainly located in cytoplasm,!and all were involved in synthesis of nucleic acids, architecture of cytoskeleton, metabolism and transport of RNAs as well as modulation of cell cycle and cell defense. These findings provide new insight for the study of interactions between host cells and C.burnetti