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wu, y.

Publications and source records attributed to wu, y..

4 recordsLinked to original sources

Sterilizing immunity against SARS-CoV-2 in hamsters conferred by a novel recombinant subunit vaccine

A safe and effective SARS-CoV-2 vaccine is essential to avert the on-going COVID-19 pandemic. Here, we developed a subunit vaccine, which is comprised of CHO-expressed spike ectodomain protein (StriFK) and nitrogen bisphosphonates-modified zinc-aluminum hybrid adjuvant (FH002C). This vaccine candidate rapidly elicited the robust humoral response, Th1/Th2 balanced helper CD4 T cell and CD8 T cell immune response in animal models. In mice, hamsters, and non-human primates, 2-shot and 3-shot immunization of StriFK-FH002C generated 28- to 38-fold and 47- to 269-fold higher neutralizing antibody titers than the human COVID-19 convalescent plasmas, respectively. More importantly, the StriFK-FH002C immunization conferred sterilizing immunity to prevent SARS-CoV-2 infection and transmission, which also protected animals from virus-induced weight loss, COVID-19-like symptoms, and pneumonia in hamsters. Vaccine-induced neutralizing and cell-based receptor-blocking antibody titers correlated well with protective efficacy in hamsters, suggesting vaccine-elicited protection is immune-associated. The StriFK-FH002C provided a promising SARS-CoV-2 vaccine candidate for further clinical evaluation.

microbiology

Rigorous anterograde trans-monosynaptic tracing of genetic defined neurons with retargeted HSV1 H129

Neuroanatomical tracing technology is fundamental for unraveling the complex network of brain connectome. Tracing tools that could spread between neurons are urgently needed, especially the rigorous trans-monosynaptic anterograde tracer is still lacking. HSV1 strain H129 was proved to be an anterograde tracer and has been used to trace neuronal networks in several reports. However, H129 has a serious defect that it was demonstrated to infect neurons via axon terminals. Thus, when using H129 to dissect output neural circuit, its terminal take up capacity should be carefully considered. Here, we report a recombinant H129 that carrying the anti-Her2 scFv in glycoprotein D to target genetically defined neurons. With the usage of helper virus complementarily expressing Her2 and gD, we can realize the elucidation of direct projection regions of either a given brain nucleus or a specific neuron type. The retargeted H129 system complements the current neural circuit tracer arsenal, which provides a rigorous and practical anterograde trans-monosynaptic tool.

neuroscience

Popularizing recombinant baculovirus-derived OneBac system for scaling-up production of all recombinant adeno-associated virus vector serotypes

Recombinant adeno-associated virus (rAAV) has been widely used as an efficient transgenic vector in biomedical research, as well as gene therapy. Serotype-associated transduction efficiency, tissue- or cell-type tropism and immunological profile are major considerations in the various applications of rAAVs. There are increasing needs for different serotypes of rAAV, either naturally isolated or artificially engineered. However, affordable and scalable production of a desired serotype of rAAV remains very difficult, especially for researchers lacking relevant experience. On the basis of our previously established single recombinant baculovirus expression vector (BEV)-derived OneBac system, we have optimized the process and expanded the rAAV production range to the full range of serotypes rAAV1-13. Firstly, the AAV Cap gene was optimized to translate by ribosome leaky scanning and the gene of interest (GOI) was cloned into the pFD/Cap-(ITR-GOI)-Rep2 shutte plasmid. Following the classical Bac-to-Bac method, sufficient BEV stock containing all rAAV packaging elements can be quickly obtained. Finally, we can repeatedly scale up production of rAAVs in one week by using a single BEV to infect suspension-cultured Sf9 cells. The rAAV1-13 show relatively high yields ranging from 5x104 to 4x105 VG/cell. More than 1x1015 VG purified rAAVs can be easily obtained from 5 L suspension-cultured Sf9 cells. As expected, rAAV serotypes 1-13 show different potencies for in vitro transduction and cell-type tropisms. In summary, the single BEV-derived OneBac system should prove popular for laboratory scaling-up production of any serotype of rAAV.

microbiology

Introduction of a precocious metamorphosis BmNPV infection in the latter half of the fifth instar silkworm larvae

The silkworm, Bombyx mori, is a complete metamorphosis insect, the model to study insect physiology and biochemistry. Bombyx mori nucleopolyhedrovirus (BmNPV) is a principal pathogen of the silkworm and its host range is restricted to silkworm larvae, requiring interaction with larvae to accomplish virus replication. Prothoracic glands (PGs) are a model for synthetic ecdysone with regulating insect growth and development. This study performed a transcriptome analysis of silkworm PGs after BmNPV infection. Transcriptome data were annotated with KEGG, GO, and shown to be of high quality by RT-qPCR. The spatial expression profiles of BmJing and BmAryl indicate that they may be specifically expressed in silkworm PGs. The RT-qPCR results of the DEGs in the PGs of BmNPV-infected larvae at 24, 48, and 72 h and at the developmental stages of days-6 and 7, comparing to day-3, reveal that the DEGs may be related to the BmNPV infection via promoting early maturation in the latter half of the silkworm fifth instar. This study is the first report on the identification of possible genes in PGs correlating with the precocious molting and metamorphosis of silkworm larvae under BmNPV infection in the latter half of the fifth instar. Our findings will help to address the interactions between BmNPV infection and host developmental response. This work provides a new perspective on BmNPV infection and host developmental response, as well as suggesting candidate genes for further research.

molecular biology