Purified human early pregnancy factor from preimplantation embryo possesses immunosuppresive properties.
This study was undertaken to determine whether early pregnancy factor secreted by preimplantation embryos has immunosuppressive properties. Human early pregnancy factor was purified from embryo growth media of in vitro fertilized ova with ion-exchange and gel filtration chromatography. During each step of purification the fractions were tested for (1) early pregnancy factor activity with the rosette inhibition assay, (2) immunosuppressive properties with a concanavalin A-stimulated lymphocyte proliferation assay, and (3) purity by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Results indicate that (1) human early pregnancy factor has a basic molecular weight of 14 kd, (2) early pregnancy factor has immunosuppressive activity, (3) polymers of early pregnancy factor also appear to be present in the embryo growth media, and (4) immunosuppressive factors other than early pregnancy factor are also secreted by preimplantation human embryos. Early pregnancy factor and other factor(s) produced by the preimplantation embryo may play a role in suppressing maternal cellular immune responses, thereby preventing maternal rejection of the embryo.
Bose
R
R
Department of Obstetrics, Gynecology and Reproductive Sciences, University of Manitoba, Winnipeg, Canada.
Cheng
H
H
Sabbadini
E
E
McCoshen
J
J
MaHadevan
M M
MM
Fleetham
J
J
D001755:Blastocyst / Q000032:analysis*; D002266:Carboxymethylcellulose Sodium; D002455:Cell Division / Q000187:drug effects; D018835:Chaperonin 10; D002845:Chromatography / Q000379:methods; D002848:Chromatography, DEAE-Cellulose; D002850:Chromatography, Gel; D003208:Concanavalin A / Q000494:pharmacology; D005260:Female; D006801:Humans; D007166:Immunosuppressive Agents; D008214:Lymphocytes / Q000166:cytology; D008970:Molecular Weight; D010455:Peptides / Q000032:analysis / Q000302:isolation & purification* / Q000494:pharmacology; D011247:Pregnancy; D011257:Pregnancy Proteins; D013491:Suppressor Factors, Immunologic
D018835:Chaperonin 10; D007166:Immunosuppressive Agents; D010455:Peptides; D011257:Pregnancy Proteins; D013491:Suppressor Factors, Immunologic; C025124:early pregnancy factor; D003208:Concanavalin A; D002266:Carboxymethylcellulose Sodium