| dc.description.abstract | The presence of antiendometrial antibodies in the sera of
women with endometriosis has been reported by several
investigators using various methodologies. Some studies suggest
that circulating and peritoneal fluid antibodies involved in
immune responses in endometriosis are directed against distinct
endometrial antigens, while others failed to detect these.
variations in methodology used have been suggested as possible
causes of false negative results. The present study was carried
out in the baboon, an animal that has been recently developed as
a model for research in endometriosis. The presence of specific
antibodies against endometrial antigens in this animal has not
been reported.
Endometrial biopsies were obtained from healthy adult
baboons of proven fertility during the luteal phase of the baboon
menstrual cycle. A protein extract of the endometrial tissue was
separated by electrophoresis on a 12.5-%.polyacrylamide gel. Sera
was obtained from 56 baboons (43 with endometriosis and 13
healthy controls without endometriosis). All the sera were
tested for IgG antibodies while only serum from 4 healthy
controls and 14 animals,with endometriosis were tested with IgM
antibodies against endometrial proteins using standard
Antibodies of the IgG class present in baboon sera
recognized several endometrial antigens but individual variation
was evident. No single specific antigen was recognized in
baboons with endometriosis. However, sera obtained from baboons
with endometriosis demonstrated a statistically significant
(p=0.05) higher number of endometrial antigens (9.2±4.5) when
compared with the controls (5.2±3.5). A positive correlation was
found to exist between number of endometrial antigens and
severity of disease. The average number of antigens was 7.9±4.4
(n=25) and 10.9±4.1 (n=18) in stages 1/11, and III/IV
respectively.
When compared to IgG, sera IgM binding was directed against
a relatively small number of endometrial antigens in baboons at
different stages of endometriosis. The IgM antibodies recognized
distinct antigens with molecular weights of 12 (57%), 50 (29%),
and 56 (21%) kilodaltons (KD) and these were restricted to
baboons with endometriosis. The 50 and 56 KD antigens were
restricted to stage III/IV disease (66.6% and 50% respectively)
while recognition of the 12 KD antigen increased with severity
of the disease (37.5% in stages I/II versus 83% in stages
Furthermore, another batch of three antigens of ,
molecular weights 14(42%), 16(43%)' and 58(57%) KD were also
present in the baboons; being more prominent in animals with
endometriosis (less than 25% in normal animals). The occurance
of the 14 and 16 KD antigens also correlated with the severity
of the disease (83% in stage III/IV disease versus 13% in stage
1/11 disease). The number of antigens recognized by IgM
antibodies also increased with the severity of disease (7.5±2.1
in stage III/IV versus 3±0.5 in stage 1/11 disease | en |
