Background: Rheumatoid arthritis (RA) is a multisystem autoimmune disease that causes marked deformity in the small joints.
Aim of the work: The aim of this work is to determine the role of nuclear factor-κB (NF-κB) and basic fibroblast growth factor (bFGF) in the histological changes of RA synovial specimens.
Patients and methods: This study was carried out on 25 RA patients who were subjected to surgery and 10 control participants with post-traumatic knee joint injury. The paraffin blocks were sectioned and the slides were stained conventionally with hematoxylin and eosin (H&E) and immunohistochemical markers for NF-κB and bFGF. Interpretation, scoring, and statistical correlation of the histological findings were performed.
Results: Histological examination and scoring of the specimens from both groups indicated a highly significant statistical increase in the number of synovial cell layers, vascular density (5.2±2.5 vs. 1.1±1.1 and 5.7±1.1 vs. 1.5±0.7 respectively; P<0.01), fibrosis (5.9±3.3 vs. 0.5±0.4), perivascular lymphocytic infiltrate (2±1.5 vs. 0), lymphoid aggregates (3.9±0.4 vs. 0), free lymphocytes (2.8±1.3 vs. 0.45±0.4), and immunohistochemical staining for NF-κB and bFGF (P<0.001) in RA patients in comparison with the control group. The number of synovial cell layers and lymphocytic aggregates showed a positive correlation with NF-κB and bFGF staining. Similarly, perivascular lymphocytic infiltrate correlated positively with bFGF staining (P<0.001).
Conclusion: NF-κB and bFGF played a crucial role in augmenting and maintaining pannus formation in the synovium of RA patients.