Description

Rheumatoid factor is an autoantibody targeting the Fc fragment of human or animal denatured IgG molecule. RF mainly includes four types of IgM, IgG, IgA and IgE. IgM is the main type of RF, and this test kit mainly detects this type. Under the direct stimulation of denatured IgG or Epstein-Barr virus, B cells in patients with rheumatoid arthritis will synthesize RF in large quantities. On the contrary, in healthy people, there are few clones of B cells that produce RF, and the soluble factors secreted by monocytes can inhibit the production of RF, which is generally difficult to be detected. Positive RF is one of the criteria for RA classification by the American College of Rheumatology, but positive RF is not the sole basis for the diagnosis of RA. RF has a positive detection rate of 80% in RA patients, 20-50% in patients with systemic lupus erythemato-sus, Sjogren’s syndrome and dermatomyositis, and even 5% in the normal elderly population.