RMr. Raphael Crumheumatoid arthritis (RA) affects 7.5 million people globally, approximately 1% of the world’s population. RA is a chronic disease, and currently, there is no known cause or cure. It is characterized by chronic inflammation and the destruction of synovial joints.

Raphael J. Crum (pictured), part of the Badylak Lab research team and a fourth year MD/PhD student in the Cellular and Molecular Pathology program at the University of Pittsburgh School of Medicine, is the lead author of an article titled “Immunomodulatory matrix-bound nanovesicles mitigate acute and chronic pristane-induced rheumatoid arthritis.”

Co-authors of the article include George S. Hussey, PhD, McGowan affiliated faculty and Assistant Professor in the University of Pittsburgh’s School of Medicine, and Stephen F. Badylak, DVM, PhD, MD, Deputy Director of the McGowan Institute and Professor in the University of Pittsburgh’s Department of Surgery.

According to the paper’s abstract:

Disease pathology [of RA] is driven by an imbalance in the ratio of pro-inflammatory vs. anti-inflammatory immune cells, especially macrophages. Modulation of macrophage phenotype, specifically an M1 to M2, pro- to anti-inflammatory transition, can be induced by biologic scaffold materials composed of extracellular matrix (ECM). The ECM-based immunomodulatory effect is thought to be mediated in part through recently identified matrix-bound nanovesicles (MBV) embedded within ECM.

Researchers then delivered isolated MBV via injection to rats with pristane-induced arthritis (PIA). The results of MBV administration were compared to the clinical standard of care, intraperitoneal (i.p.) administration of methotrexate (MTX). The overall results of the study “show that the therapeutic efficacy of MBV is equal to that of MTX for the management of acute and chronic pristane-induced arthritis and, further, this effect is associated with modulation of local synovial macrophages and systemic myeloid populations.”

The article, published in Nature’s Portfolio Series, npj Regenerative Medicine, can be read in its entirety here.