Human Leukocyte Antigen (HLA) B27

General Information

HLA-B27 is a protein complex located on the surface of the leukocyte membrane.

The purpose of the test is to determine the presence or absence of the HLA-B27 antigen (protein) to assess the likelihood of an autoimmune disease associated with this marker.

HLA-B27 antigen is detected in 90-95% of patients with clinical and radiological manifestations of ankylosing spondylitis and in 10-20% of patients with only radiological manifestations.

HLA-B27 is a very heterogeneous protein, therefore up to 35 subtypes have been discovered. Subtypes differ from each other in amino acid sequence.

During antigen recognition by T lymphocytes, HLA-B27 plays a dual role:

1. On the one hand, it recognizes CD8 in the thymus⁺ antigenic receptors of cytotoxic T lymphocytes,
2. On the other hand, it participates in peripheral tissue CD8⁺ in the binding of cytotoxic T lymphocytes.

There is no molecular similarity between HLA-827 and KLEBSLIELLA PNEUMONIAE protein, which may indicate a bacterial pathogenesis of ankylosing spondylitis.

It is possible that antigenic similarity causes a cross-immune response. Autoimmune diseases associated with hla-b27:

• Reiter's syndrome (reactive arthritis)
• Juvenile idiopathic arthritis
• Psoriatic arthritis
• Inflammatory bowel diseases

Preliminary preparation: not necessary

Study material: Venous blood

in the norm  HLA-B27 is negative.