Determination of Circulating Antiendometrial Antibodies in Patients with Endometriosis by Western Blot and Enzyme - linked Immunosorbent Assay

Moon, Shin Yong; Choi, Young Min; Kim, Seok Hyun; Lee, Jin Yong; Kim, Jung Gu; Kang, Soon Beom; Suh, Chang Seok

Abstract

OBJECTIVES
To investigate whether endometrial proteins with molecular weight(MW) of 92 kilodalton(kDa) may be a specific antigen involved in autoimmunity in endometriosis and to evaluate the efficacy of enzyme-linked immunosorbent assay(ELISA) in determining antiendometrial antibodies, compared with Western blot.
METHODS
Sera of forty-eight patients with endometriosis, 21 patients with normal control patients, 7 patients with Mayer-Rokitansky-Kustner-Hauser(MRKH) syndrome and cord sera of 22 male neonates(experimental controls) were tested for the presence of antibodies against endometrial proteins by Western blot and ELISA. All statistics were performed by Fishers exact teast and Student's t-test.
RESULTS
Fourteen(29.1%), 18.8%, and 33.3% of sera from patients with endometriosis had immunoglobulin (IgG) antibodies that were reactive against endometrial proteins of MW of 71, 92, 103 kDa while any sera from experimental controls did not show any reactivity against these antigens. Overall, threr were specific IgG antiendometrial antibodies detectable by Western blot in 56.3% of patients with endometriosis and in a normal eontrol patient. The binding activities of serum IgG to endometrial proteins were higher in patients with endometriosis than other groups. Circulating IgG antiendometrial antibodies were detected by ELISA in 54.3% of 35 patients with endometriosis and in 2 normal control patients. The concordance rate between ELISA and Western blot in determining the presence of antiendometrial antibodies was 78.3%.
CONCLUSIONS
Ninety-two kDa endometrial protein is a specific antigen eliciting IgG responses in endometriosis. ELISA may be an useful method in screening autoimmune endometriosis.