We demonstrate that human multipotent MSCs are present in second-trimester amniotic fluid. Considering the great potential of cellular therapy using fetal stem cells and the feasibility of intrauterine fetal tissue engineering, amniotic fluid may provide an excellent alternative source for investigation of human MSCs.

The efficacy and safety of maternal tenofovir disoproxil fumarate (TDF) in reducing mother-to-infant hepatitis B virus (HBV) transmissions is not clearly understood. We conducted a prospective, multicenter trial and enrolled 118 hepatitis B surface antigen (HBsAg)-and hepatitis B e antigen-positive pregnant women with HBV DNA 7.5 log 10 IU/mL. The mothers received no medication (control group, n 5 56, HBV DNA 8.22 6 0.39 log 10 IU/mL) or TDF 300 mg daily (TDF group, n 5 62, HBV DNA 8.18 6 0.47 log 10 IU/mL) from 30-32 weeks of gestation until 1 month postpartum. Primary outcome was infant HBsAg at 6 months old. At delivery, the TDF group had lower maternal HBV DNA levels (4.29 6 0.93 versus 8.10 6 0.56 log 10 IU/mL, P < 0.0001). Of the 121/123 newborns, the TDF group had lower rates of HBV DNA positivity at birth (6.15% versus 31.48%, P 5 0.0003) and HBsAg positivity at 6 months old (1.54% versus 10.71%, P 5 0.0481). Multivariate analysis revealed that the TDF group had lower risk (odds ratio 5 0.10, P 5 0.0434) and amniocentesis was associated with higher risk (odds ratio 6.82, P 5 0.0220) of infant HBsAg positivity. The TDF group had less incidence of maternal alanine aminotransferase (ALT) levels above two times the upper limit of normal for 3 months (3.23% versus 14.29%, P 5 0.0455), a lesser extent of postpartum elevations of ALT (P 5 0.007), and a lower rate of ALT over five times the upper limit of normal (1.64% versus 14.29%, P 5 0.0135) at 2 months postpartum. Maternal creatinine and creatinine kinase levels, rates of congenital anomaly, premature birth, and growth parameters in infants were comparable in both groups. At 12 months, one TDF-group child newly developed HBsAg positivity, presumably due to postnatal infection and inefficient humoral responses to vaccines. Conclusions: Treatment with TDF for highly viremic mothers decreased infant HBV DNA at birth and infant HBsAg positivity at 6 months and ameliorated maternal ALT elevations. (HEPATOLOGY 2015;62:375-386) D espite the 75%-90% reduction of chronic hepatitis B viral (HBV) infection following universal infant immunization, active/passive immunoprophylaxis has not eradicated mother-toinfant HBV transmission. [1][2][3][4] Approximately 10% of chronic HBV infections cannot be prevented.5-7 The major risks of chronic HBV infection in the immunization era are maternal hepatitis B surface antigen (HBsAg)/hepatitis B e antigen (HBeAg) positivity and high maternal viral load.5-9 Moreover, after immunoprophylaxis, children with HBV infection have a higher risk of developing hepatocellular carcinoma. 10,11 To achieve the goal of global eradication of HBV infection, better strategies aimed at interrupting Abbreviations: ALT, alanine aminotransferase; anti-HBs, antibody to hepatitis B surface antigen; D0, day 0, initiation of TDF treatment (baseline); D1M, 1 month after TDF treatment; HBeAg, hepatitis B e antigen; HBsAg, hepatitis B surface antigen; HBV, hepatitis B virus; P0, at partum; PXM, X months postpartum; SNR, signal-to-noise ratio; TDF, tenofov...

Recent evidence has shown that amniotic fluid may be a novel source of fetal stem cells for therapeutic transplantation. We previously developed a two-stage culture protocol to isolate a population of amniotic fluid-derived mesenchymal stem cells (AFMSCs) from second-trimester amniocentesis. AFMSCs maintain the capacity to differentiate into multiple mesenchymal lineages and neuron-like cells. It is unclear whether amniotic fluid contains heterogeneous populations of stem cells or a subpopulation of primitive stem cells that are similar to marrow stromal cells showing the behavior of neural progenitors. In this study, we showed a subpopulation of amniotic fluid-derived stem cells (AF-SCs) at the single-cell level by limiting dilution. We found that NANOG- and POU5F1 (also known as OCT4)-expressing cells still existed in the expanded single cell-derived AF-SCs. Aside from the common mesenchymal characteristics, these clonal AF-SCs also exhibit multiple phenotypes of neural-derived cells such as NES, TUBB3, NEFH, NEUNA60, GALC, and GFAP expressions both before and after neural induction. Most importantly, HPLC analysis showed the evidence of dopamine release in the extract of dopaminergic-induced clonal AF-SCs. The results of this study suggest that besides being an easily accessible and expandable source of fetal stem cells, amniotic fluid will provide a promising source of neural progenitor cells that may be used in future cellular therapies for neurodegenerative diseases and nervous system injuries.

Circulating fetal nucleated cells (CFNCs) in maternal blood offer an ideal source of fetal genomic DNA for noninvasive prenatal diagnostics (NIPD). We developed a class of nanoVelcro microchips to effectively enrich a subcategory of CFNCs, i.e., circulating trophoblasts (cTBs) from maternal blood, which can then be isolated with single-cell resolution by a laser capture microdissection (LCM) technique for downstream genetic testing. We first established a nanoimprinting fabrication process to prepare the LCM-compatible nanoVelcro substrates. Using an optimized cTB-capture condition and an immunocytochemistry protocol, we were able to identify and isolate single cTBs (Hoechst+/CK7+/HLA-G+/CD45−, 20 μm > sizes > 12 μm) on the imprinted nanoVelcro microchips. Three cTBs were polled to ensure reproducible whole genome amplification on the cTB-analysis. Using maternal blood samples collected from expectant mothers carrying a single fetus, the cTB-derived aCGH data were able to detect fetal genders and chromosomal aberrations, which had been confirmed by standard clinical practice. Our results support the use of nanoVelcro microchips for cTB-based noninvasive prenatal genetic testing, which holds potential for further development toward future NIPD solution.