Measurement of cytokine and adhesion molecule expression in synovial tissue by digital image analysis

• Published in: Annals of the rheumatic diseases 2001-03, Vol.60 (3), p.296-298
• Main Authors: Kraan, M C, Smith, M D, Weedon, H, Ahern, M J, Breedveld, F C, Tak, P P
• Format: Article
• Language: English
• Subjects: Adult; Aged; Arthritis, Rheumatoid - metabolism; Biological and medical sciences; Case-Control Studies; Cell adhesion & migration; Cell adhesion molecules; Cell Adhesion Molecules - analysis; Concise Report; Cytokines; Diagnostic imaging; Digital electronics; digital image analysis; Female; Humans; Image Processing, Computer-Assisted; Interleukin-1 - analysis; Investigative techniques, diagnostic techniques (general aspects); Male; Measurement; Medical sciences; microscopy; Middle Aged; Osteoarticular system. Muscles; Pathology. Cytology. Biochemistry. Spectrometry. Miscellaneous investigative techniques; Reproducibility of Results; Rheumatism; Rheumatoid arthritis; Sensitivity and Specificity; Staining and Labeling; Statistics, Nonparametric; Studies; Synovial Membrane - metabolism; Synovial membranes; synovial tissue
• ISSN: 0003-4967; 1468-2060
• DOI: 10.1136/ard.60.3.296

OBJECTIVE Digital image analysis (DIA) offers the opportunity to quantify the stained area and staining intensity when synovial tissue (ST) is investigated by immunohistochemical analysis. This study aimed at determining the sensitivity of DIA compared with semiquantitative analysis (SQA). METHODS Paired ST samples were obtained from the knee joint of 10 patients with rheumatoid arthritis (RA) with active disease and after follow up when complete clinical remission was achieved. ST samples of 10 subjects with non-inflammatory knee pain served as controls. Immunohistochemistry with antibodies against interleukin 1β (IL1β) and vascular cell adhesion molecule 1 (VCAM-1) was applied using two staining protocols with 3-amino-9-ethylcarbazole (AEC) orp-diethylaminobenzaldehyde (DAB) as dye. All sections were analysed semiquantitatively (0–4) and DIA of up to a maximum of 60 high power fields (HPF). The average integrated optical density was calculated as the product of the stained area (corrected for total tissue area) and the optical density. RESULTS Both SQA and DIA enabled the assessment of differences in IL1β and VCAM-1 expression between ST from active RA, RA in remission, and controls. SQA and DIA showed excellent correlations (IL1βr s=0.867; p