Mother-to-child transmission of HIV-1: the role of HIV-1 variability and the placental barrier

HIV-1 replication and gene expression occur at higher levels in neonatal blood naive and memory T-lymphocytes compared with adult blood cells

Our previous study has shown that HIV-1 replicated at higher levels in neonatal (cord) blood monocytes/macrophages and T-lymphocytes compared with adult blood cells. However, it is not known whether this differential HIV-1 replication also occurs in naive and/or memory T-lymphocytes. We, therefore, compared HIV-1 replication in CD3(+) and CD4(+) naive (CD45RA(+)) and memory (CD45RO(+)) T-lymphocytes isolated from five cord and adult blood donors. We found that HIV-1 replicated at higher levels in both CD3(+) and CD4(+) CD45RA(+) and CD45RO(+) T-lymphocytes isolated from cord blood compared with adult blood. In addition, there was no difference in the cell surface expression of CD4, CXCR4 and CCR5 on cord blood CD45RA(+) and CD45RO(+) T-lymphocytes compared with adult blood cells. Furthermore, we found that there was an increase in HIV-1 gene expression in cord blood CD45RA(+) and CD45RO(+) T-lymphocytes compared with adult blood cells by using a single-cycle replication competent HIV-1-NL4-3-Env(-)R(+) luciferase amphotropic virus, which measures HIV-1 transcriptional activity independent of CD4 and CXCR4 or CCR5 expression. In summary, HIV-1 replicated at higher levels in cord blood CD45RA(+) and CD45RO(+) T-lymphocytes compared with adult blood cells and this differential replication is influenced at the level of HIV-1 gene expression.

Relationship of hepatitis B virus infection of placental barrier and hepatitis B virus intra-uterine transmission mechanism

AIM: To explore the mechanism of intra-uterine transmission, the HBV infection status of placental tissue and in vitro cultured placental trophoblastic cells was tested through in vivo and in vitro experiments.

METHODS: A variety of methods, such as ELISA, RT-PCR, IHC staining and immunofluorescent staining were employed to test the HBV marker positive pregnant women's placenta and in vitro cultured placental trophoblastic cells.

RESULTS: The HBV DNA levels in pregnant women's serum and fetal cord blood were correlated. For those cord blood samples positive for HBV DNA, their maternal blood levels of HBV DNA were at a high level. The HBsAg IHC staining positive cells could be seen in the placental tissues and the presence of HBV DNA detected. After co-incubating the trophoblastic cells and HBV DNA positive serum in vitro, the expressions of both HBsAg and HBV DNA could be detected.

CONCLUSION: The mechanism of HBV intra-uterine infection may be due to that HBV breaches the placental barrier and infects the fetus.

Relationship between the infection and apoptosis of placental trophoblastic cells and the mechanism of hepatitis B virus intrauterine transmission

AIM: To study the mechanism of hepatitis B virus (HBV) intrauterine transmission by infecting the cultured human trophoblastic cells in vitro.

METHODS: Primary cultured trophoblastic cells from human first-trimester placenta and serial subcultivation of JEG-3 cell line were investigated. The primary cultured and subcultured cells were cultured in the HBV-infected serum for 8 to 48 h. The appearance of the cells and intercellular conjunctions were observed under inverted microscope. The protein expression of HBsAg and HBcAg were detected by cell immunofluorescence and immunohistochemical staining. HBV DNA of the infected trophoblastic cells was detected by fluorescent quantitative polymerase chain reaction (FQ-PCR). Cell apoptosis was tested by TUNEL technique.

RESULTS: The appearance of the cells and intercellular conjunction were not obviously affected after co-culturing with HBV-positive serum. Cell immunofluorescence and immunohistochemistry showed that HBsAg and HBcAg can be detected in the trophoblastic cells after co-culturing with HBV-infected serum for 8, 24 and 48 h, and HBsAg-positive cells were at the most level after 24-h culturing (8 h: 18.0% ± 3.67%; 24 h: 30.6% ± 2.88%; 48 h: 24.8% ± 4.21%). FQ-PCR demonstrated the existence of HBV DNA in the infected cells. TUNEL exhibited that the co-culturing resulted in an increase of cell apoptosis (24 h: 18.6 % ± 3.05%; 48 h: 26.8% ± 2.86%; P < 0.01).

CONCLUSION: The infection of trophoblastic cells may be one of the routes for HBV passing through the placental membrane. HBV infection may induce the apoptosis of trophoblastic cells, which may be a protective mechanism for placental membrane to block up the vertical transmission of HBV.

The past, present and future of nongonadal LH/hCG actions in reproductive biology and medicine

The past and present published studies reaffirm that nongonadal LH and hCG actions are real and here to stay. These actions have led to a better understanding of the biology of the hormones and more importantly begin to pave the way for novel therapies in reproductive medicine and in other areas.