Endotoxins are common exogenous pyrogens. Excessive endotoxins in medical devices and injections can lead to serious consequences such as sepsis, septic shock, and even death. Therefore, endotoxin detection plays a crucial role in medical, pharmaceutical, and food sectors. The wide application of Limulus amebocyte lysate (LAL) has led to a sharp decline in the number of horseshoe crabs. Moreover, the LAL assay has limitations such as interbatch variations and difficulty in quantification. The recombinant factor C (rFC) assay is stable between batches, highly sensitive, and capable of quantitation, and thus it can be used as an alternative for the LAL assay. However, the high cost and complex procedures involved in producing recombinant factor C have limited the widespread application of this method. In order to simplify the preparation and reduce the production cost of recombinant factor C, this study focuses on the production of recombinant factor C based on the baculovirus expression system. Multiple measures such as a high-yield and anti-apoptotic vector qBac-IIIG, the optimal signal peptide, and the optimized codon were used to reach the goal of endotoxin detection with cell supernatant. This method simplifies the steps of protein purification. The sensitivity of the supernatant reached 0.05 EU/mL in a 1-L fermentation system, and 500 000 detecting reactions can be supported per liter of fermentation broth. This study increases the yield and activity of recombinant factor C, simplifies the procedures of protein purification, and reduces the cost, laying a foundation for the promotion and application of recombinant factor C in endotoxin detection.
Animals ; Recombinant Proteins/genetics* ; Horseshoe Crabs/chemistry* ; Baculoviridae/metabolism* ; Endotoxins/analysis* ; Protein C/biosynthesis* ; Genetic Vectors/genetics* ; Arthropod Proteins/genetics* ; Enzyme Precursors ; Serine Endopeptidases

Foot-and-mouth disease (FMD) is one of the major animal infectious diseases in the world. All cloven-hoofed animals are susceptible to FMD. Vaccination is still the first choice for the prevention and control of FMD. mRNA vaccines can be rapidly designed, synthesized, and produced on a large scale in vitro, and they can induce effective protective immune responses, demonstrating the advantages of rapid development, easy preparation, and low biosafety risks. The design of untranslated regions is a key to enhancing the expression and efficacy of mRNA vaccines. In order to generate an efficient FMD mRNA vaccine, we designed three FMD P12A3C expression vectors with different untranslated regions and synthesized corresponding mRNAs. By comparing expression efficiency of these vectors and their mRNAs at different time points and in different cell lines, we found that the mRNA P12A3C-UTR3 had the best expression and universality. This study laid a foundation for the development of mRNA vaccines against FMD and provided a theoretical basis for the optimal sequence design of efficient mRNA.
Foot-and-Mouth Disease Virus/genetics* ; Animals ; RNA, Messenger/biosynthesis* ; Foot-and-Mouth Disease/immunology* ; Antigens, Viral/biosynthesis* ; Viral Vaccines/biosynthesis* ; Genetic Vectors/genetics* ; Cell Line ; Vaccines, DNA/immunology*

Rice stripe virus (RSV) transmitted by the small brown planthopper causes severe rice yield losses in Asian countries. Although viral nuclear entry promotes viral replication in host cells, whether this phenomenon occurs in vector cells remains unknown. Therefore, in this study, we systematically evaluated the presence and roles of RSV in the nuclei of vector insect cells. We observed that the nucleocapsid protein (NP) and viral genomic RNAs were partially transported into vector cell nuclei by utilizing the importin α nuclear transport system. When blocking NP nuclear localization, cytoplasmic RSV accumulation significantly increased. In the vector cell nuclei, NP bound the transcription factor YY1 and affected its positive regulation to FAIM. Subsequently, decreased FAIM expression triggered an antiviral caspase-dependent apoptotic reaction. Our results reveal that viral nuclear entry induces completely different immune effects in vector and host cells, providing new insights into the balance between viral load and the immunity pressure in vector insects.
Animals ; Cell Nucleus ; Hemiptera/metabolism* ; Insect Vectors/genetics* ; Insecta ; Nucleocapsid Proteins/metabolism* ; Oryza ; Plant Diseases ; Tenuivirus/metabolism* ; Virus Replication

Pathogens like bacteria and protozoa, which affect human and animal health worldwide, can be transmitted by vectors like ticks. To investigate the epidemiology and genetic diversity of bacteria and protozoans carried by ticks in Chengmai county of Hainan province, China, 285 adult hard ticks belonging to two species [
Anaplasmataceae/isolation & purification* ; Animals ; Chaperonin 60/genetics* ; China ; Citrate (si)-Synthase/genetics* ; Coccidia/isolation & purification* ; Coxiellaceae/isolation & purification* ; Insect Vectors/microbiology* ; Islands ; Ixodidae/microbiology* ; Phylogeny ; Piroplasmia/isolation & purification* ; RNA, Ribosomal, 16S/genetics* ; RNA, Ribosomal, 18S/genetics*

The 2019 novel coronavirus disease (COVID-19), caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has occurred in China and around the world. SARS-CoV-2-infected patients with severe pneumonia rapidly develop acute respiratory distress syndrome (ARDS) and die of multiple organ failure. Despite advances in supportive care approaches, ARDS is still associated with high mortality and morbidity. Mesenchymal stem cell (MSC)-based therapy may be an potential alternative strategy for treating ARDS by targeting the various pathophysiological events of ARDS. By releasing a variety of paracrine factors and extracellular vesicles, MSC can exert anti-inflammatory, anti-apoptotic, anti-microbial, and pro-angiogenic effects, promote bacterial and alveolar fluid clearance, disrupt the pulmonary endothelial and epithelial cell damage, eventually avoiding the lung and distal organ injuries to rescue patients with ARDS. An increasing number of experimental animal studies and early clinical studies verify the safety and efficacy of MSC therapy in ARDS. Since low cell engraftment and survival in lung limit MSC therapeutic potentials, several strategies have been developed to enhance their engraftment in the lung and their intrinsic, therapeutic properties. Here, we provide a comprehensive review of the mechanisms and optimization of MSC therapy in ARDS and highlighted the potentials and possible barriers of MSC therapy for COVID-19 patients with ARDS.
Adoptive Transfer ; Alveolar Epithelial Cells ; pathology ; Animals ; Apoptosis ; Betacoronavirus ; Body Fluids ; metabolism ; CD4-Positive T-Lymphocytes ; immunology ; Clinical Trials as Topic ; Coinfection ; prevention & control ; therapy ; Coronavirus Infections ; complications ; immunology ; Disease Models, Animal ; Endothelial Cells ; pathology ; Extracorporeal Membrane Oxygenation ; Genetic Therapy ; methods ; Genetic Vectors ; administration & dosage ; therapeutic use ; Humans ; Immunity, Innate ; Inflammation Mediators ; metabolism ; Lung ; pathology ; physiopathology ; Mesenchymal Stem Cell Transplantation ; methods ; Mesenchymal Stem Cells ; physiology ; Multiple Organ Failure ; etiology ; prevention & control ; Pandemics ; Pneumonia, Viral ; complications ; immunology ; Respiratory Distress Syndrome, Adult ; immunology ; pathology ; therapy ; Translational Medical Research

Coronavirus disease 2019 (COVID-19) pandemic has caused a total of 55 928 327 confirmed cases and 1 344 003 deaths as of November 19, 2020. But so far the origin of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) that causes this pandemic has remained undetermined. The purpose of this study is to review the current research of SARS-CoV-2 and the existing problems therein, which may provide inspiration for further researches. Existing evidence suggested that SARS-CoV-2 may be derived from bat coronavirus 40-70 years ago. During the evolution, this virus underwent extensive variations in the process of mutations and natural selection. Different genomic regions of SARS-CoV-2 may have different selection pressures, but all of which increase the difficulty of tracing the origin of this virus. A wide variety of animals have been considered as potential hosts of SARS-CoV-2, including cats, lions, tigers, dogs and minks. SARS-CoV-2 has a chance to transmit from humans to animals and can be transmitted among animals. Current research evidence has shown that China is not the original source of SARS-CoV-2. It is still unclear how the virus spreads to human, and efforts are still need to be made to explore the origin of SARS-CoV-2, its hosts and intermediate hosts, and the mechanism of its transmission across different species of animals.
Animals ; COVID-19/transmission* ; Cats ; China ; Chiroptera/virology* ; Disease Vectors ; Dogs ; Evolution, Molecular ; Humans ; SARS-CoV-2/classification*

Gene therapy plays an important role in Alzheimer's disease (AD). In recent years, the research on gene delivery vector has gradually transferred from adenovirus vector, adeno-associated virus vector and lentivirus vector to liposomes and nanomaterial carrier systems. Graphene, the newest member of nanomaterial carrier system, has attracted extensive attention for its well permeability and biocompatibility. The methods of gene therapy can be divided into direct and indirect method. The stem cell therapy, which is the most-well studied one, belongs to the indirect method. In the gene therapy of AD, the selection of appropriate carrier and method will determine the therapeutic effect.
Alzheimer Disease ; therapy ; Dependovirus ; Gene Transfer Techniques ; Genetic Therapy ; Genetic Vectors ; Humans

Rickettsial infections (Rickettsioses) are the causes of acute fever found in Thailand. It is classified as acute febrile illnesses transmitted by bloodsucking arthropod vectors (tick, flea, and chigger). This research investigated pathogens of scrub typhus in vectors from Bangkaew District, Phatthalung Province. A total of 303 pools of vector samples were ticks (Rhipicephalus sanguineus, R. microplus, and Haemaphysalis sp.), fleas (Ctenocephalides felis orientis, C. f. felis, and C. canis), and chiggers (Leptotrombidium deliense, Aschoschoengastia indica, Blankaartia acuscutellaris and Walchia disparunguis pingue) collected from reservoir hosts (dogs and rodents). The 17 and 56 kDa gene of Rickettsia causing scrub typhus were found in 29% of ticks and 98% of flea. DNA sequence analysis reveeled the detected strains were R. asembonensis and Rickettsia sp. cf1 and 5.The chiggers, 1%, were infected with Rickettsia strain TA763, a pathogen of scrub typhus.
Animals ; Arthropod Vectors ; Cats ; Felis ; Fever ; Orientia tsutsugamushi ; Rickettsia ; Scrub Typhus ; Sequence Analysis, DNA ; Siphonaptera ; Thailand ; Ticks ; Trombiculidae

Objectives: This scoping review aimed to support a landscape analysis to identify lessons learned about intersectoral collaborations (ISCs) by describing their existing models in the context of dengue, malaria and yellow fever. Methods: A scoping review following the methodology of Joanna Briggs Institute was performed using the following inclusion criteria: studies involving humans; studies discussing intersectoral collaborations, malaria/dengue/yellow fever, and prevention or control at any level; and studies in countries endemic for the aforementioned diseases. Studies were screened using Covidence, while data were extracted using NVivo. Results: Of the 7,535 records retrieved, 69 were included in the qualitative analysis. Most ISCs were initiated by multilateral organizations and ministries of health, and none by communities. Strategies included advocacy, health education, research, public health measures, resource mobilization, service delivery and training; mostly employed on a community level. Monitoring and evaluation were mostly formative, ongoing, and participatory. Gaps included administrative and policy barriers, resource shortages, and inadequate research and training. Conclusions Multiple models of ISC exist in the literature. There is a need to develop a comprehensive framework for an effective and sustainable multisectoral approach for the prevention and control of VBDs ensuring adequate resources, active stakeholders, and strategies that span the entire socio-ecological spectrum.
Dengue ; Disease Vectors ; Intersectoral Collaboration ; Malaria ; Vector Borne Diseases

Lyssaviruses, including Rabies virus, Duvenhage virus, European bat lyssavirus 1, European bat lyssavirus 2, Australian bat lyssavirus, and Irkut virus (IRKV), have caused human fatalities, but infection of IRKV in dogs has not been previously reported. In China, a dead dog that previously bit a human was determined to be infected with IRKV. Pathogenicity tests revealed that IRKVs can cause rabies-like disease in dogs and cats after laboratory infection. The close relationship between humans and pets, such as dogs and cats, may generate a new spillover-spreading route for IRKV infection. Therefore, additional attention should be paid to trans-species infection of IRKV between bats and dogs or dogs and humans through investigation of the prevalence and circulation patterns of IRKV in China.
Animals ; China ; Disease Transmission, Infectious ; Disease Vectors ; Dog Diseases ; transmission ; virology ; Dogs ; Genes, Viral ; Humans ; Lyssavirus ; genetics ; isolation & purification ; pathogenicity ; Male ; Phylogeny ; Rhabdoviridae Infections ; transmission ; veterinary ; virology