1. PLoS One. 2013;8(3):e58285. doi: 10.1371/journal.pone.0058285. Epub 2013 Mar 7.

Analysis of the Membrane Proteome of Ciprofloxacin-Resistant Macrophages by
Stable Isotope Labeling with Amino Acids in Cell Culture (SILAC).

Caceres NE, Aerts M, Marquez B, Mingeot-Leclercq MP, Tulkens PM, Devreese B, Van 
Bambeke F.

Pharmacologie cellulaire et moléculaire, Louvain Drug Research Institute,
Université catholique de Louvain, Brussels, Belgium.

Overexpression of multidrug transporters is a well-established mechanism of
resistance to chemotherapy, but other changes may be co-selected upon exposure to
drugs that contribute to resistance. Using a model of J774 macrophages made
resistant to the fluoroquinolone antibiotic ciprofloxacin and comparing it with
the wild-type parent cell line, we performed a quantitative proteomic analysis
using the stable isotope labeling with amino acids in cell culture technology
coupled with liquid chromatography electrospray ionization Fourier transform
tandem mass spectrometry (LC-ESI-FT-MS/MS) on 2 samples enriched in membrane
proteins (fractions F1 and F2 collected from discontinuous sucrose gradient).
Nine hundred proteins were identified with at least 3 unique peptides in these 2 
pooled fractions among which 61 (F1) and 69 (F2) showed a significantly modified 
abundance among the 2 cell lines. The multidrug resistance associated protein
Abcc4, known as the ciprofloxacin efflux transporter in these cells, was the most
upregulated, together with Dnajc3, a protein encoded by a gene located downstream
of Abcc4. The other modulated proteins are involved in transport functions, cell 
adhesion and cytoskeleton organization, immune response, signal transduction, and
metabolism. This indicates that the antibiotic ciprofloxacin is able to trigger a
pleiotropic adaptative response in macrophages that includes the overexpression
of its efflux transporter.

PMCID: PMC3591400
PMID: 23505477  [PubMed - in process]