The novel anti-rheumatic compound Rabeximod impairs differentiation and function of human pro-inflammatory dendritic cells and macrophages

• Rabeximod (9-chloro-2,3-dimethyl-6-(N,N-dimethylaminoethylamino-2-oxoethyl)-6H-indolo[2,3-b]quinoxaline) is a synthetic compound that is currently being developed for the treatment of rheumatoid arthritis (RA). Here, we investigated the effects of Rabeximod on the functionality of human antigen-presenting cells (APCs) of myeloid origin. Different subsets of professional APCs were generated from human monocytes in vitro and simultaneously treated with different doses of Rabeximod. Although Rabeximod had no effect on the differentiation of monocytes into anti-inflammatory macrophages (AI-Ms), this compound impaired monocyte differentiation into monocyte-derived dendritic cells (MDCs) and pro-inflammatory allostimulated macrophages (Allo-Ms). MDCs that were treated with Rabeximod resulted in a significant decrease in their ability to pinocytose antigens, while no effect was exerted by the drug on the ability of Allo-Ms and AI-Ms to phagocytose. Furthermore, we observed a significant reduction in the allostimulatory ability of MDCs and Allo-Ms after treatment with Rabeximod, although this compound did not affect the low immunostimulatory capacity of AI-Ms. Conversely, the effect of Rabeximod in influencing cytokine secretion by APCs appeared to be limited. In conclusion, Rabeximod impairs differentiation of monocytes into different pro-inflammatory APCs, leading to impaired immunostimulatory abilities of these cells. Our observations shed light on the cellular mode of action and the immunomodulatory effect of Rabeximod.

Subject headings

MEDICIN OCH HÄLSOVETENSKAP  -- Medicinska och farmaceutiska grundvetenskaper -- Immunologi inom det medicinska området (hsv//swe)

MEDICAL AND HEALTH SCIENCES  -- Basic Medicine -- Immunology in the medical area (hsv//eng)

Keyword

Rheumatoid arthritis

Inflammation

Autoimmunity

Dendritic cells

Macrophages

Immunology

Immunologi

immunologi

Immunology

Publication and Content Type

ref (subject category)

art (subject category)