A study of human leukocyte antigen G expression in hydatidiform moles.
OBJECTIVE
Human leukocyte antigen G (HLA-G) is a nonclassic major histocompatibility gene normally expressed only in extravillous trophoblasts throughout pregnancy. It may be responsible in part for the successful evasion of the hemiallogenic trophoblasts from maternal immune surveillance. We investigated whether HLA-G is expressed in molar pregnancies.


METHODS
We examined 5 complete hydatidiform mole specimens and 5 partial hydatidiform mole specimens to determine whether HLA-G is expressed by immunohistochemistry and by RNA in situ hybridization analysis.


RESULTS
We found that both the protein and RNA of HLA-G is expressed in complete and partial hydatidiform moles.


CONCLUSIONS
HLA-G RNA and protein are expressed in molar pregnancies. HLA-G expression is independent of embryonic development and may therefore be an integral part of placental development. Furthermore, expression of HLA-G in the complete hydatidiform mole, a naturally occurring androgenote, confirms expression of the paternal allele of HLA-G. Imprinting of HLA-G is therefore unlikely to play a role in protecting fetal trophoblasts from maternal immune rejection.
Goldman-Wohl
D
D
Department of Obstetrics and Gynecology, Hadassah University Hospital, Jerusalem, Israel.
Ariel
I
I
Greenfield
C
C
Hochner-Celnikier
D
D
Lavy
Y
Y
Yagel
S
S
D005260:Female; D015870:Gene Expression; D006680:HLA Antigens / Q000032:analysis* / Q000235:genetics*; D059951:HLA-G Antigens; D015395:Histocompatibility Antigens Class I / Q000032:analysis* / Q000235:genetics*; D006801:Humans; D006828:Hydatidiform Mole / Q000276:immunology*; D007150:Immunohistochemistry; D017403:In Situ Hybridization; D010920:Placenta / Q000276:immunology; D011247:Pregnancy; D012333:RNA, Messenger / Q000032:analysis; D014327:Trophoblasts / Q000276:immunology; D014594:Uterine Neoplasms / Q000276:immunology*
D006680:HLA Antigens; D059951:HLA-G Antigens; D015395:Histocompatibility Antigens Class I; D012333:RNA, Messenger