OBJECTIVETo explore the feasibility of membrane protein-based two-dimensional electrophoresis (2-DE) in the investigations of chondrocyte-related diseases and its complementarity with total protein-based 2-DE.

METHODSKnee cartilage samples were obtained to isolate the chondrocytes with type II collagenase/hyaluronidase digestion. The membrane proteins and total proteins were extracted and loaded separately onto PH3.0-10.0 non-linear gel strip for 2-DE analysis. The qualities of membrane protein-based 2-DE gels were evaluated, and the difference between the distribution profiles of the membrane protein spots and that of the total protein were observed and their complementarities were evaluated.

RESULTSMembrane protein-based 2-DE generated high-quality gel images, and on each gel 412.3±13.5 protein spots were identified. These spots were distributed in the region of isoelectric point pH 5.0-9.0. In the gel images generated by the total proteins, 564.3±5.9 protein spots were identified in each image, and the spots were distributed in the region of isoelectric point pH 3.0-7.0.

CONCLUSIONMembrane protein-based 2-DE of the chondrocytes can generate high-quality gel images, and the isoelectric distribution of the protein spots is complementary to that of total protein, which provides valuable information for chondrocyte-related diseases.