New Bone Chewing Role for B Cells in Rheumatoid Arthritis
Thursday, April 14, 2016
Image of rheumatoid arthritis patient joint tissue taken by Javier Rangel-Moreno, Ph.D., on the cover
New Bone Chewing Role for B Cells in Rheumatoid Arthritis
Thursday, April 14, 2016
Image of rheumatoid arthritis patient joint tissue taken by Javier Rangel-Moreno, Ph.D., on the cover of Arthritis & Rheumatology.
University of Rochester Medical Center researchers have uncovered a new mechanism of bone erosion and a possible biomarker for rheumatoid arthritis (RA). The group is the first to demonstrate that immune cells, called B cells, contribute directly to the breakdown of bone in RA by producing a signaling molecule called RANKL.
Jennifer Anolik, M.D., Ph.D., professor of Medicine at the University of Rochester Medical Center and author of the study found that B cells extracted from RA patient blood produced more RANKL and led to production of more bone chewing cells, called osteoclasts, than B cells from the blood of healthy volunteers. This effect was even greater when study authors inspected B cells extracted from RA patients’ joint fluid and tissue.
“The novel finding is that B cells contribute to bone erosion in RA by producing RANKL,” says Anolik. “The other striking thing is that RA patient B cells produce more RANKL - especially in the joint itself.”
Jennifer Anolik, M.D., Ph.D.
The fact that Anolik and her collaborators, including Lianping Xing, B. Med, Ph.D., professor of Pathology and Laboratory Medicine, were able to demonstrate their results in RA joint tissue gives their study an added level of disease relevance. A lot of studies investigating human diseases look at blood samples rather than target tissues, because blood is much easier to collect. Thanks to a unique collaboration between the Rheumatologists and Orthopedic surgeons in the Center for Musculoskeletal Research at URMC, Anolik and her team were able to do studies in joint tissue collected during RA patient surgeries.
According to the latest data from the Centers for Disease Control and Prevention, approximately 1.5 million adults are affected by RA in the US. These patients’ immune systems attack their own joint tissue causing painful stiffness and swelling of the joints as well as erosion of the bones in the joint that can cause permanent damage. These symptoms often leave patients unable to perform normal activities of daily life, like dressing themselves.
Because B cells are essential for the immune syste