The Transfer of IgG-Subclasses From Mother to Fetus in the Korean Population. |
Goo Sang Kim1, Sang Il Lee2, Ka Young Chang3, Kwang Ho Lee3 |
1Department of Obstetrics & Gynecology, School of Medicine, Inha University 2Department of Pediatrics, School of Medicine, Inje University 3Department of Anatomy, School of Medicine, Seoul National University |
한국인 면역글로불린-G 아형의
태반통과에 관한 연구 |
김구상1, 이상일2, 장가용3, 이광호3 |
1인하대학교 의과대학 산부인과학교실 2인제대학교 의과대학 소아과학교실 3서울대학교 의과대학 해부학교실 |
Received: 22 August 1989 • Accepted: 27 November 1989 |
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Abstract |
Normal IgG is now divided into four subclasses; IgGl, IgG2, IgG3 and IgG4. Each subclass has its
unique characteristics. The different subclass compositions of antibodies are raised in humans against
different immunogenic materials such as vaccinations or microoraganisms. All the IgG subclasses are
reported to be transferable from mother to fetus through the placenta, but there have been some
controversies in case of IgG2.
For the delineation of the transplacental passage of IgG-subclasses in the Korean population, we
studied the IgG-subclasses levels in paired maternal and cord sera. We also observed the transfer rate
of each subclass in different gestational ages, sexes, and birth weights.
A hundred and eight paired sera were collected at the time of delivery from the gestational ages
ranging from 23 weeks to 44 weeks. Radial immunodiffusion kits (The Binding Site Ltd., Birmingham,
England) were used for the measurement of IgG-subclasses serum levels.
At 36 weeks of gestation, cord serum levels of IgGl and IgG3 reached the maternal serum levels,
and their transplacental transferabilities were 103% and 101% on the average. 89% of the maternal
IgG4 was transferred to the fetus at 37 weeks of gestation. The amount of trans placental passage of
these three IgG-subclasses did not alter in the succeeding gestational ages, and the transplacental
transfer rates reached 104%, 102% and 89% at term. However, only 61% of maternal IgG2 was
transferred at 36 weeks of gestation and its transfer rate increased there-after to reach 73% at term.
Therefore, the placenta may play a selective barrier for the passage of IgG2, and the transferability
of each IgG-subclass is IgGl = IgG3 > IgG4 > IgG2.
The sex and birth weight did not affect the transplacental passage of IgG-subclasses. |
Key Words:
IgG-subclass, Transplacental Immunity |
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