Figure 1
Detection of RasGRF1 protein expression in rheumatoid arthritis and non-rheumatoid arthritis synovial tissue. (a) Representative staining of rheumatoid arthritis (RA) synovial tissue with control and anti-Ras guanine nucleotide-releasing factor 1 (anti-RasGRF1) antibodies. (b) Representative staining of RA and osteoarthritis (OA) synovial tissue with anti-RasGRF1 antibodies. Staining was developed with amino-ethylcarbazole (red), and was counterstained with Mayer's hematoxylin. Magnification × 100. (c) Quantitative analysis of Ras signaling protein expression in RA and non-RA (OA and reactive arthritis) synovial tissue. Integrated optical densities (IOD)/mm2, corrected for nucleated cells, for staining of the synovial sublining (sub) and intimal lining (lin) layer of 10 RA patients and 11-non-RA (four inflammatory OA, seven reactive arthritis) patients with anti-RasGRF1 antibodies. IOD values were calculated by computer-assisted image analysis. Box plots, 25th to 75th percentiles; lines within each box, median; lines outside boxes, 10th and 90th percentiles. Bars indicate statistically significant differences in protein expression between sublining and intimal lining layer tissues within diagnostic groups and between diagnostic groups. *P < 0.05, **P < 0.01, ***P < 0.005.