CD14+ Dendritic-Shaped Cells Functioning as Dendritic Cells in Rheumatoid Arthritis Synovial Tissues

Area of Science:

• Immunology
• Rheumatology

Background:

• CD14+ cells with dendritic morphology and CD90 expression are found in rheumatoid arthritis (RA) synovial tissues.
• The precise function of these CD14highCD90intermediate(int) cells in RA pathogenesis remains unclear.

Purpose of the Study:

• To investigate the dendritic cell-differentiation potential of CD14highCD90int cells in RA.

Main Methods:

• Quantified CD14highCD90int cells in RA synovial tissues and peripheral blood.
• Assessed dendritic cell differentiation potential by measuring cytokine levels (IL-6, TNF-α) and marker expression (CD83, HLA-DR).
• Co-cultured synovial cells with lymphocytes to examine activation.

Main Results:

• CD14highCD90int cells were abundant in RA synovial tissues and elevated in peripheral blood of RA patients.
• Dendritic cell differentiation culture increased inflammatory cytokines and significantly upregulated CD83 and HLA-DR in CD14highCD90int cells.
• Co-culture with lymphocytes led to increased cell numbers and inflammatory cytokines after dendritic cell induction.

Conclusions:

• CD14+ cells expressing CD90 migrate from blood to RA synovial tissues.
• CD14highCD90int cells differentiate into HLA-DR+ dendritic cells upon contact with lymphocytes.
• These dendritic cells contribute to chronic inflammation in RA.