Long-standing Link Between ankylosing spondylitis and HLA-B27 Explained

Results could explain how immune system mistakenly targets health tissue in ankylosing spondylitis (AS).

Ankylosing spondylitis (AS) is a type of arthritis that mainly affects the joints of the spine. 

Ankylosing spondylitis is an inflammatory condition that involves the spine and skeleton of the head and trunk. The disorder causes inflammation and pain in joints in the spine, pelvis and other parts of the skeleton. In addition, parts of the spine, the hips or the sacroiliac joints where the hips join the lower back, may fuse, or grow, together.

UCSF Health 

 Long-standing Link Between AS and HLA-B27 Explained 

 Writer: Steve Bryson PhD | December 22, 2022

“Our findings that T cells at the sites of pathology recognize HLA-B*27 bound to both self and microbial antigens adds a very important layer of understanding to these complex conditions that also feature strong inflammatory signatures,” Gillespie said. “Our hope is that this work will one day pave the way for more targeted therapies, not only for these conditions but ultimately, for other autoimmune diseases.”

Co-first author Michael Paley, MD, PhD, of Washington University, added, “For ankylosing spondylitis, the average time between initial symptoms and actual diagnosis is seven to eight years. Shortening that time with improved diagnostics could make a dramatic impact on patients’ lives, because treatment could be initiated earlier.

“As for therapeutics, if we could target these disease-causing T cells for elimination, we could potentially cure a patient or maybe even prevent the disease in people with the high-risk genetic variant. There’s a lot of potential for clinical benefit here.”

 Read full article at Ankylosing Spondylitis News 

HLA-B27 Testing

The HLA-B27 test checks for a protein on your white blood cells. HLA-B27 causes the immune system to attack healthy cells. Up to 95 percent of people who do have ankylosing spondylitis are HLA-B27 positive.

The test is a simple blood draw. Your doctor may order the test if he or she suspects your symptoms are caused by an autoimmune or autoinflammatory condition. Your doctor should also help you interpret your test results, but you can find the basics below.

• What does HLA-B27 negative mean?
  • If you are HLA-B27 negative, it means you don’t have HLA-B27 on your white blood cells.
• Can you be HLA-B27 negative and still have ankylosing spondylitis?
  • You can be negative for HLA-B27 and still have ankylosing spondylitis. 
• What does HLA-B27 positive mean?
  • If you are HLA-B27 positive, it means you do have some HLA-B27 on your white blood cells. You inherited the HLA-B27 gene from your parents.
• Can you be HLA-B27 positive and not have ankylosing spondylitis?
• Not everyone who tests positive for HLA-B27 in the blood has an immune or inflammatory disorder.
• If you are HLA-B27 positive, you have a 10 percent chance (or less) of developing a spondyloarthritis condition.
• If you do not have ankylosing spondylitis, you may have a different condition. The presence of HLA-B27 in you blood means you are at greater risk of developing such a disease. SOURCE

VIDEO: Ankylosing Spondylitis: Visual Explanation for Students