Automated routine HLA-B27 typing by flow cytometry

An increasing demand for HLA-B27 typing as one of the tests used in the diagnosis of ankylosing spondylitis had led us to develop a rapid, automated, flow cytometric assay using whole blood and an HLA-B27 specific monoclonal antibody FD705. This article shows the data from 2093 samples tested during a 2 year period of routine HLA-B27 typing. 21.6% were clearly HLA-B27 positive whilst 73.2% were HLA-B27 negative, the remaining 5.2% required further testing before assignment of HLA-B27 status. Additional work was carried out on blood samples from individuals positive for the newly described subtype HLA-B2708.