Question

In rheumatoid arthritis, which type of cells are prominently present in the hypertrophied synovial lining?

• A. B cells
• B. T cells
• C. Macrophages
• D. Dendritic cells

Hint:

Which cell, with fibroblasts, builds up the thickened synovial intimal lining?

Answer 1

The Correct Option is C

Step 1: Normally the synovial lining (intimal layer) is only 1 to 3 cells thick. In rheumatoid arthritis this layer becomes greatly hypertrophied, reaching 8 to 10 cells in thickness.
Step 2: The two main cell populations forming this thickened intimal layer are fibroblast-like synoviocytes and macrophage-like synoviocytes. Among the listed options, macrophages are the prominent cells of this lining - option c.
Step 3: T cells, B cells and dendritic cells are abundant in rheumatoid disease too, but they accumulate mainly in the deeper sublining and form lymphoid aggregates, not the surface intimal lining asked about here, so options a, b and d are not the best answer.
Step 4: Hence the macrophage (together with fibroblasts) is the dominant cell of the hypertrophied synovial lining in rheumatoid arthritis.