Expression of CD44 adhesion molecules on human placentae.
OBJECTIVE
This study was performed to characterize CD44 expression in human placentae.


METHODS
We conducted reverse transcriptase polymerase chain reaction (RT-PCR) analyses of CD44H (hematopoietic form, also called CD44s) and CD44R1 (epithelial form) in 14 normal term placentae, and immunohistochemical analysis of CD44H and CD44v6 in 31 placentae (25 term and 6 first-trimester).


RESULTS
All 14 term placentae expressed CD44H (double bands) suggesting expression of alternative isoforms on the placentae. CD44R1 was expressed on 3 of 14 (21.4%) term placentae. Immunohistochemical analysis revealed expression of CD44H in all the placentae examined. However, positive staining for CD44v6 was observed in 3 of 6 (50%) first-trimester and only 6 of 25 (24%) term placentae showing decreased expression on term placentae. Positive staining for CD44v6 was observed on the trophoblast surface of immature villi especially in the sub-chorionic area where hypoxic conditions prevail.


CONCLUSIONS
These results suggest that CD44 splicing variants might play a role in the invasion of trophoblast into maternal tissue in early pregnancy.
Choi
Chel Hun
CH
Department of Obstetrics and Gynecology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea.
Roh
Cheong Rae
CR
Kim
Tae-Joong
TJ
Choi
Yoon-La
YL
Lee
Jeong-Won
JW
Kim
Byoung-Gie
BG
Lee
Je-Ho
JH
Bae
Duk-Soo
DS
D017398:Alternative Splicing; D005260:Female; D006801:Humans; D018960:Hyaluronan Receptors / Q000235:genetics / Q000378:metabolism*; D007150:Immunohistochemistry; D010920:Placenta / Q000378:metabolism*; D011247:Pregnancy; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014327:Trophoblasts / Q000378:metabolism*
D018960:Hyaluronan Receptors