A quarter of HBsAg-negative Ultrio+ and dHBV- donations in China are likely given by potentially infectious low-viral-load occult carriers. Although this has no implication for blood safety, the testing algorithm needs to be redesigned to more efficiently discriminate between true and false NAT reactivity.

The HBV NAT yield in blood donors in Qingdao is 0.06% (38/65,800). This study confirmed the value of NAT for interdicting HBV-positive donations and preventing transfusion-transmitted HBV infections.

Qualified donations after routine blood donor screening still carry a potential risk for transmitting HEV. The major genotypes in Chinese donors in this study were Genotypes 1 and 4.

Low-density lipoprotein receptor-related protein 6 (LRP6) promotes metastasis in numerous types of cancer; however, its role in trophoblast cells has been less frequently reported. In the present study, the effects of up-and downregulation of LRP6 on trophoblast cells were investigated accordingly. The study aimed to develop a therapeutic target for gestational choriocarcinoma. The expression levels of LRP6 in pre-eclampsia (PE) tissues, trophoblast cell lines and gestational choriocarcinoma cells were determined using reverse transcription-quantitative polymerase chain reaction (RT-qPcR) assay. double-luciferase reporter analysis was conducted to detect the regulatory gene of LRP6. Furthermore, the proliferative, migratory and invasive abilities of trophoblasts and gestational choriocarcinoma cells were determined by ccK-8, wound healing, and Transwell assays, respectively. The expression levels of the genes and proteins of interest [matrix metalloproteinase (MMP)-2, MMP-9, tissue inhibitor of metalloproteinase-1 (TIMP-1), and TIMP-2] associated with tumor cell invasion were measured by performing RT-qPcR and western blotting, respectively. The National center for Biotechnology Information database revealed that LRP6 was relatively highly expressed in placental tissues, but was poorly expressed in PE tissues and trophoblast cell lines. The upregulation of LRP6 not only increased the activity, migration and invasion of trophoblast cells, but it also promoted the expression of MMP-2 and MMP-9, whereas it inhibited the expression levels of TIMP-1 and TIMP-2. Such results followed the opposite trend to those of downregulation of LRP6 in gestational choriocarcinoma cells. Moreover, LRP6 was predicted to be the target gene for microRNA (miR)-346, which was highly expressed in PE tissues and trophoblast cell lines. The present study also revealed that LRP6 could reverse the effects of miR-346 on the proliferation, migration and invasion of trophoblast cells. Therefore, considered collectively, the results of the present study have demonstrated that LRP6 is involved in the proliferation, migration and invasion of trophoblast cells via miR-346, and that LRP6 may serve as a potential target in cancer treatment.

Gene expression labeling and conditional manipulation of gene function are important for elaborate dissection of gene function. However, contemporary generation of pairwise dual-function knockin alleles to achieve both conditional and geno-tagging effects with a single donor has not been reported. Here we first developed a strategy based on a flipping donor named FoRe to generate conditional knockout alleles coupled with fluorescent allele-labeling through NHEJ-mediated unidirectional targeted insertion in zebrafish facilitated by the CRISPR/ Cas system. We demonstrated the feasibility of this strategy at sox10 and isl1 loci, and successfully achieved Cre-induced conditional knockout of target gene function and simultaneous switch of the fluorescent reporter, allowing generation of genetic mosaics for lineage tracing. We then improved the donor design enabling efficient one-step bidirectional knockin to generate paired positive and negative conditional alleles, both tagged with two different fluorescent reporters. By introducing Cre recombinase, these alleles could be used to achieve both conditional knockout and conditional gene restoration in parallel; furthermore, differential fluorescent labeling of the positive and negative alleles enables simple, early and efficient realtime discrimination of individual live embryos bearing different genotypes prior to the emergence of morphologically visible phenotypes. We named our improved donor as Bi-FoRe and demonstrated its feasibility at the sox10 locus. Furthermore, we eliminated the undesirable bacterial backbone in the donor using minicircle DNA technology. Our system could easily be expanded for other applications or to other organisms, and coupling fluorescent labeling of gene expression and conditional manipulation of gene function will provide unique opportunities to fully reveal the power of emerging single-cell sequencing technologies.