F(ab')2 segment is the active component of immunoglobulin G autoantibody generation in patients with endometriosis.
OBJECTIVE
To determine if the low titer antiendometrial antibody detection by indirect immunofluorescence (IIF) in the sera of patients with endometriosis is because of specific antigen-antibody interactions.


METHODS
Sera of selected patients subjected to separation of immunoglobulin fragments by ammonium sulfate precipitation and pepsin digestion and tested by IIF. In a comparative method, a fragment, crystallizable (Fc) flooding technique was used to determine the active component.


METHODS
Sera obtained preoperatively in the outpatient and results matched with surgical findings.


METHODS
Patients 45 years of age or less presenting for gynecological surgery who had signed an informed consent for the drawing of preoperative blood.


METHODS
None.


METHODS
Indirect immunofluorescence was graded according to the intensity of staining and the lowest dilution at which staining occurred.


RESULTS
All of the sera of the 11 patients with endometriosis exhibited F(ab')2 specific staining but none exhibited Fc fragment staining. None of the 7 control patients displayed F(ab')2 or Fc fragment staining.


CONCLUSIONS
F(ab')2 fragment is the active component of an immunologically specific interaction when antiendometrial antibodies are detected in the sera of patients with endometriosis.
Wild
R A
RA
Department of Obstetrics and Gynecology, University of Oklahoma Health Sciences Center, Oklahoma City 73190.
Medders
D
D
Zhang
R J
RJ
D000917:Antibody Formation; D001323:Autoantibodies / Q000276:immunology*; D004715:Endometriosis / Q000276:immunology* / Q000473:pathology; D005455:Fluorescent Antibody Technique; D006801:Humans; D007140:Immunoglobulin Fab Fragments / Q000032:analysis / Q000276:immunology*; D007074:Immunoglobulin G / Q000276:immunology*; D009367:Neoplasm Staging; D013194:Staining and Labeling; D014407:Tumor Cells, Cultured
D001323:Autoantibodies; D007140:Immunoglobulin Fab Fragments; D007074:Immunoglobulin G