A monoclonal antibody to an early pregnancy factor-induced suppressor factor (EPF-S1) disrupts implantation in mice.
OBJECTIVE
The importance of EPF during pregnancy has been established previously but the importance of the EPF-induced suppressor factor EPF-S1 in pregnancy has to date been unaddressed. Investigations were therefore conducted in order to study this.


METHODS
Monoclonal antibodies to EPF-S1 were produced, and one antibody, designated R2T gamma, was characterized. Mated mice were passively immunized with R2T gamma and the effect on implantation determined.


RESULTS
Characterization of anti-EPF-S1 R2T gamma revealed that it cross-reacted with EPF-S1 of different MHC restriction but not with EPF or EPF-S2. When injected into mated mice on days 1 to 4, R2T gamma had no effect on pregnancy but when injections continued to day 5, pregnancy was affected; the number of embryos implanted on day 7 were significantly less than the number of corpora lutea counted, signifying embryonic loss.


CONCLUSIONS
These studies show that anti-EPF-S1 R2T gamma disrupts implantation in mice when injected on days 1 to 5 of pregnancy but not when injected on days 1 to 4, demonstrating that EPF-S1 exerts its effects around the time of implantation.
Athanasas-Platsis
S
S
University of Queensland, Department of Surgery, Royal Birsbane Hospital, Australia.
Hoskin
M J
MJ
Rolfe
B E
BE
Cavanagh
A C
AC
Morton
H
H
D000818:Animals; D000911:Antibodies, Monoclonal / Q000009:adverse effects*; D018835:Chaperonin 10; D003429:Cross Reactions; D010064:Embryo Implantation / Q000276:immunology*; D005260:Female; D007166:Immunosuppressive Agents / Q000494:pharmacology*; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D010455:Peptides / Q000276:immunology*; D011247:Pregnancy; D011257:Pregnancy Proteins; D051381:Rats; D017208:Rats, Wistar; D013491:Suppressor Factors, Immunologic
D000911:Antibodies, Monoclonal; D018835:Chaperonin 10; D007166:Immunosuppressive Agents; D010455:Peptides; D011257:Pregnancy Proteins; D013491:Suppressor Factors, Immunologic; C025124:early pregnancy factor