Effect of maternal immunopotentiation on apoptosis-associated molecules expression in teratogen-treated embryos.
OBJECTIVE
Potentiation of the maternal immune system was shown by us to affect the embryonic response to teratogenic insults. In order to understand better the mechanisms underlying that phenomenon, we explored the effect of maternal immunopotentiation by rat splenocytes on the early stages of the embryonic response to cyclophosphamide (CP).


METHODS
Immunopotentiated CP-treated embryos were analysed for cell cycle changes by flow cytometry, while cell proliferation and apoptosis were assessed by 5'-bromo-2'-deoxyuridine (BrdU) incorporation and terminal deoxynucleotidyl transferase (TdT)-mediated dUTP-biotin nick-end labeling (TUNEL) respectively. The expression of the p65 subunit of NF-kappaB, IkappaBalpha, Bax, bcl-2 and p53 was assessed by flow cytometry.


RESULTS
Exposure to CP resulted in significant growth retardation and in the appearance of cellular damage, a reduction in cell proliferation and the appearance of apoptotic cells, which were all found to be delayed in immunopotentiated embryos. In parallel, CP-treated embryos demonstrated a reduction in the percentage of p65- or IkappaBalpha-positive cells, while the percentage of bcl-2- or p53-positive cells increased initially and decreased later. Those changes were normalized by maternal immunopotentiation when tested at 24 hrs after exposure to the teratogen.


CONCLUSIONS
Our data implicate maternal immunopotentiation to protect the embryo against teratogenic insults, possibly through its effect on the expression of p65, bcl-2 or p53.
Savion
Shoshana
S
Department of Cell and Developmental Biology, Sackler School of Medicine, Tel Aviv University, Ramat Aviv, Tel Aviv 69978, Israel. shoshans@post.tau.ac.il
Aroch
Ilan
I
Mammon
Keren
K
Orenstein
Hasida
H
Fein
Amos
A
Torchinsky
Arkady
A
Toder
Vladimir
V
D000014:Abnormalities, Drug-Induced / Q000276:immunology*; D000818:Animals; D017209:Apoptosis / Q000187:drug effects / Q000276:immunology; D002453:Cell Cycle / Q000187:drug effects / Q000276:immunology; D049109:Cell Proliferation / Q000187:drug effects; D003520:Cyclophosphamide / Q000008:administration & dosage* / Q000009:adverse effects; D004622:Embryo, Mammalian / Q000187:drug effects / Q000276:immunology* / Q000378:metabolism / Q000473:pathology; D005260:Female; D005317:Fetal Growth Retardation / Q000276:immunology*; D020672:I-kappa B Proteins / Q000096:biosynthesis; D007114:Immunization; D008431:Maternal-Fetal Exchange / Q000276:immunology; D051379:Mice; D008813:Mice, Inbred ICR; D009153:Mutagens / Q000009:adverse effects; D011247:Pregnancy; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000096:biosynthesis; D051381:Rats; D013154:Spleen / Q000276:immunology / Q000473:pathology; D016159:Tumor Suppressor Protein p53 / Q000096:biosynthesis; D019892:eIF-2 Kinase / Q000096:biosynthesis
C083487:I kappa B beta protein; D020672:I-kappa B Proteins; D009153:Mutagens; D019253:Proto-Oncogene Proteins c-bcl-2; D016159:Tumor Suppressor Protein p53; D003520:Cyclophosphamide; D019892:eIF-2 Kinase