PURPOSE: All IgG subclasses such as IgG1, IgG2, IgG3 and IgG4 can be transferred from mother to fetus through the placenta, though the amount of each IgG subclass is different from one another. Maternally acquired immunity might have an important role for the protection against the infections. We studied transplacental passage of IgG subclasses. METHODS: In this study, we observed the transplacental passage of IgG-subclasses in 22 paired samples of maternal and full- term fetal cord sera. Gestational ages varied from 37 to 42 weeks. The concentrations of IgG subclasses were analyzed by radial immunodiffusion method using commercialized Human IgG Subclass Combi kit. RESULTS: The concentrations of IgG subclasses, IgG1, IgG3 and IgG4 in cord sera exceed the maternal concentration, while IgG2 did not. The ratio of serum levels of cord to maternal were 1.330+/-0.067 for IgG1, 0.859+/-0.039 for IgG2, 1.258+/-0.058 for IgG3 and 1.159+/-0.038 for IgG4. CONCLUSION: This result suggested that the placenta may play a selective barrier for passage of IgG2.
Fetus* ; Gestational Age ; Humans ; Immunity, Maternally-Acquired ; Immunodiffusion ; Immunoglobulin G* ; Mothers ; Placenta

Most common causative agents for hand, foot and mouth disease (HFMD) are enterovirus 71 (EV-A71) and coxsackievirus A16 (CV-A16). The symptomatic and asymptomatic cases could transmit the disease in population. Many sero-epidemiological surveys were launched to estimate the sero-incidence of EV-A71 and CV-A16 enterovirus, the susceptibility of different sub-population, and to observe the dynamics of neutralizing antibody. A literature search of sero-epidemiological study focused on EV-A71 or CV-A16 was conducted via PubMed and China Hospital Knowledge Database. Based on the 20 selected studies, the different age groups' antibody level, the susceptibility, the dynamics of antibody and sero-incidence of EV-A71 or CV-A16 were analyzed. From our results, the antibody level against EV-A71 or CV-A16 in neonates was associated with their mothers, which was similar with that of adults. The antibody level against EV-A71 or CV-A16 in neonates dropped to lowest level at one years-old, and started to dramatically increase until four years-old, and reached a plateau at five years-old. In conclusion, the infants aged 6-12 months were the priority group to receive vaccination when the EV-A71 vaccine is licensed in the future.
Adaptive Immunity ; Adult ; Age Factors ; Antibodies, Neutralizing ; Child ; China ; Enterovirus ; Enterovirus A, Human ; Humans ; Immunity, Maternally-Acquired ; Infant ; Infant, Newborn ; Mothers ; Seroepidemiologic Studies ; Vaccination

In order to asses congenital cytomegalovirus (CMV) infection in Korea, five hundred and seventy five pregnant women (mean age 29.5 +/- 3.8 yrs., mean gestational age at test 37.5 +/- 6.7 weeks) visiting the prenatal clinic at Severance Hospital, Seoul, Korea were studied. CMV IgG antibody was present in 96% (552/575) and IgM antibody was present in 0.7% (4/575) of the pregnant women by the third trimester. Four of 445 cord sera were positive for CMV IgM antibody (0.9%). Urine samples from 514 newborns were tested for the evaluation of congenital CMV infection. Six (1.2%) of 514 newborns excreted CMV in their urine. All the congenitally infected infants had subclinical involvement at birth and during the 12 months of the follow-up period. These results indicate that Korean pregnant women were highly immunized against CMV by the third trimester. Furthermore this study suggests that the rate of congenital CMV infection is relatively as high as rates previously reported from other countries, although there is a very high prevalence of maternal immunity. The incidence of maternal primary infection during pregnancy seems to be rare and therefore most congenital infections in Korea might be following by maternal reactivation or reinfection.
Adult ; Cytomegalovirus Infections/congenital/*epidemiology/immunology/metabolism ; Female ; Follow-Up Studies ; Humans ; *Immunity, Maternally-Acquired ; Immunoglobulin G/blood ; Immunoglobulin M/blood ; Infant, Newborn ; Korea/epidemiology ; Pregnancy

OBJECTIVETo investigate possible protective effect of maternal immunoglobulin G (IgG) against N-methyl-D-aspartate-mediated neurotoxicity on primary-cultured rat hippocampal neurons and the mechanism of the effect.

METHODSAn in vitro system had been developed for the study of hippocampal neurons. Intracellular lactic dehydrogenase (LDH) release was used as a marker to measure the rates of neuronal damage. The cells were stained with Trypan blue to measure the rate of neuronal death.

RESULTSN-methyl-D-aspartate (NMDA) at a concentration of 50 micromol/L resulted in increased release of LDH and the cell mortality (P < 0.01, respectively). Maternal IgG of different concentration (10 mg/L, 100 mg/L) inhibited NMDA-induced intracellular LDH release (P < 0.01, respectively) and cell mortality (P < 0.05, 0.01, respectively), and larger dose had stronger effect (P < 0.05).

CONCLUSIONSMaternal IgG had protective effect on primary-cultured rat hippocampal neurons injured by NMDA and the effect was dose-dependent.

Animals ; Animals, Newborn ; Cell Death ; drug effects ; Cell Survival ; drug effects ; Cells, Cultured ; Excitatory Amino Acid Agonists ; Female ; Hippocampus ; cytology ; drug effects ; metabolism ; pathology ; Immunity, Maternally-Acquired ; immunology ; Immunoglobulin G ; biosynthesis ; isolation & purification ; pharmacology ; Immunologic Factors ; biosynthesis ; isolation & purification ; pharmacology ; L-Lactate Dehydrogenase ; analysis ; biosynthesis ; Male ; N-Methylaspartate ; Neurons ; drug effects ; metabolism ; pathology ; Organ Culture Techniques ; Pregnancy ; Rats ; Rats, Wistar