A Comprehensive Review on the Role of Interleukin-40 as a Biomarker for Diagnosing Inflammatory Diseases

Figure 3

Adapted from [22]. IL-40 in the synovial membrane of patients with rheumatoid arthritis (RA) and osteoarthritis (OA). Intensive IL-40 positivity was observed in RA, especially in the hyperplastic-lining layer and within the inflammatory infiltrates of the RA synovium. Moderate expression of IL-40 was detected in the endothelial cells. IL-40 expression was quite sparse with only few IL-40 positive immune cells within the OA synovial tissue. Rabbit IgG was used as an isotype control. The white arrows point to the hyperplastic-lining layer, and the black arrows point to capillaries. Representative images of immunohistochemistry staining are shown at ×100 magnification, detailed view at ×200 magnification (RA, n = 5; OA, n = 4).