In vitro distinction between proinflammatory and antiinflammatory macrophages with gadolinium-liposomes and ultrasmall superparamagnetic iron oxide particles at 3.0T.

BACKGROUND: Inflammation involves a heterogeneous macrophage population, for which there is no readily available MR assessment method. PURPOSE: To assess the feasibility of distinguishing proinflammatory M1 and antiinflammatory M2 macrophages at MRI enhanced with gadolinium liposomes or ultrasmall superparamagnetic iron oxide particles. STUDY TYPE: In vitro. SPECIMEN: We employed cultured RAW macrophages. M0 macrophages were polarized with lipopolysaccharide (LPS) or interleukin-4 (IL-4), resulting in M1 or M2 macrophages. The macrophages were incubated with gadolinium (±rhodamine) liposomes or iron oxide particles and cell pellets were prepared for MRI. FIELD STRENGTH/SEQUENCE: Transverse relaxation rates and quantitative susceptibility were obtained at 3.0T with multiecho turbo spin echo and spoiled gradient echo sequences. ASSESSMENT: MRI results were compared with confocal microscopy, flow cytometry, and expression of endocytosis, M1 and M2 genes. STATISTICAL TESTS: Mann-Whitney and Kruskal-Wallis tests were performed. RESULTS: Higher transverse relaxation rates and susceptibility were observed in M1 than in M2 and M0 macrophages (P < 0.01 both with liposomes and USPIO) and significantly different susceptibility in M2 and M0 macrophages (P < 0.01 both with liposomes and USPIO). These MRI results were confirmed at confocal microscopy and flow cytometry. LPS macrophages displayed M1 gene expression, whereas IL-4 macrophages showed M2 polarization and lower endocytosis gene expression rates. DATA CONCLUSION: These in vitro results show that it is feasible to distinguish between proinflammatory M1 and antiinflammatory M2 macrophages according to their level of contrast agent uptake at MRI. LEVEL OF EVIDENCE: 1 Technical Efficacy: Stage 1 J. Magn. Reson. Imaging 2019;49:1166-1173.

Development and Preliminary Application of a Peptide Mass Fingerprinting Technique in Proteome Research.

Proteome means the total proteins expressed by the genome in a cell or tissue. Two-dimensional electrophoresis (2-DE) is now the most powerful separating technique and the key separation method used in proteome. Peptide mass fingerprinting (PMF) is becoming a widely used and vastly developed technique for protein identification in 2-D gels. In this research, a systematic method to identify the proteins in polyacrylamide gels by PMF was developed. Proteins were digested in-gel by enzyme and the masses of generated peptides were measured by matrix assisted laser desorption ionization time of flight mass spectrometry (MALDI-TOF-MS). The data obtained from PMF were used in protein database search and the protein identification. The proteins from human lung cancer cells isolated by 2-DE were subjected to identification by the PMF method developed in this work. Three spots of proteins in gel were identified as G3P2_HUMAN, UBL1_ HUMAN and TPIS_HUMAN.

[Progress in human disease proteomics].

In the post-genomic era, with the accomplishment of the sequence mapping of human genome, one of the most important tasks for life science is the explanation and identification of human genome, that is, about 1/3 genes of human genome and their functions need further revealment and verification on the level of protein. In the field of functional proteomics, the human disease proteomics shows great potential in the discovery of new molecular targets and biomarkers for medicine and biopharmacy. In this article, we have made a concise discussion on the current status, existing problems and future development in the research of human disease proteomics both in and out of China.