(HLA (A, B, C-
Normal range: Negative
Comment: Histocompatibility (HLA typing) antigens are glycopeptides present on the cell surface of most tissues in the body, essential for immune recognition. Leukocytes of each individual bear a unique HLA antigen code may allow prediction of which immunologic diseases each individual is susceptible to. HLA B-27 for example is a risk prediction marker for ankylosing spondylitis and essential in donor selection of organ transplant. HLA genes site is known to have multiple alleles, they are all coexpressed. The serologically detected antigens can be classified into 4 main groups: HLA-A, HLA-B, HLA-C, HLA-D R, P&Q
Sample: Heparin, whole blood
HLA B27-
Normal range: Negative
Comment: Although the tissue type antigen HLA B 27 is present in 4-8%5 of the normal population, it is present in 88-96% of patients with ankylosing spondylitis. Can be detected serologically or by flowcytometry
Sample: Heparin, whole blood
HLA B5-
Normal range: Negative
Comment: There is close association between its presence and Behcets disease
Sample: Heparin, whole blood
HLA DR-
Normal range: Negative
Comment: HLA-DR play a major role in antigen presentation and graft rejection. Typing of HLA-DR antigens can be determined seroloically or more specifically at the genetic level using the PCR technique
Sample: EDTA, whole blood