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Rabies virus (RABV) infection can initiate the host immune defence response and induce an antiviral state characterized by the expression of interferon (IFN)-stimulated genes (ISGs), among which the family of genes of IFN-induced protein with tetratricopeptide repeats (Ifits) are prominent representatives. Herein, we demonstrated that the mRNA and protein levels of Ifit1, Ifit2 and Ifit3 were highly increased in cultured cells and mouse brains after RABV infection. Recombinant RABV expressing Ifit3, designated rRABV-Ifit3, displayed a lower pathogenicity than the parent RABV in C57BL/6 mice after intramuscular administration, and Ifit3-deficient mice exhibited higher susceptibility to RABV infection and higher mortality during RABV infection. Moreover, compared with their individual expressions, co-expression of Ifit2 and Ifit3 could more effectively inhibit RABV replication in vitro. These results indicate that murine Ifit3 plays an essential role in restricting the replication and reducing the pathogenicity of RABV. Ifit3 acts synergistically with Ifit2 to inhibit RABV replication, providing further insight into the function and complexity of the Ifit family.

Severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) is a newly emerging, highly transmitted and pathogenic coronavirus that has caused global public health events and economic crises. As of March 4, 2021, more than 100 million people have been infected, more than 2 million deaths have been reported worldwide, and the numbers are continuing to rise. To date, a specific drug for this lethal virus has not been developed to date, and very little is currently known about the immune evasion mechanisms of SARS-CoV-2. The aim of this review was to summarize and sort dozens of published studies on PubMed to explore the pathogenic features of SARS-CoV-2, as well as the possible immune escape mechanisms of this virus.

The innate immune response is the first line of defense against viral invasion and pro-inflammatory chemokines and cytokines have a critical function in the innate immune responses against virus infections. The ability of a rabies virus (RABV) to induce the expression of chemokines and cytokines can lead to viral clearance from the central nervous system (CNS), whereas the ability to evade such expression and activation contributes to virulence and pathogenicity. In this review, the crucial contribution of chemokines/cytokines to clearing RABV from the CNS is discussed, including recruiting leukocytes into the CNS, enhancement of blood brain barrier permeability and activation of various immune cells that are essential for viral clearance. In addition, recombinant RABV expressing cytokines and chemokines can induce elevated innate and adaptive immune responses which result in clearing an established wild-type RABV infection in the CNS.

Peroxynitrite is an ion acting as a powerful oxidant and nucleophile, which plays a key role in the inflammation and aging process by nitrating tyrosine or tryptophan residues of the proteins. Nitration of a target protein is considered to be a proper method to study the behavioral change of the proteins being nitrated. The commonly used methods for peroxynitrite preparation in vitro usually contain high concentration of sodium hydroxide, which easily induces hydrolysis of target proteins. Accordingly, the method for peroxynitrite preparation was optimized in vitro by changing the sequence of hydrochloric acid and sodium hydroxide added. After different amount of hydrochloric acid added to the system following sodium nitrite, peroxynitrite can be yielded in a concentration up to 60 mM with sodium hydroxide as low as 17 mM. More importantly, biological activity of the target protein was well maintained after protein nitration since low sodium hydroxide was used.

Loop-mediated isothermal amplification (LAMP) is a widely used isothermal nucleic acid amplification method. Here we developed a new closed-tube colorimetric method for judging LAMP with a novel metal indicator. First, the metal indicator, acid chrome blue K (ACBK), was evaluated in the LAMP reaction with various combinations of reaction reagents, such as reaction buffer, dNTP mixtures, primer mixtures, or Mg2+. We found that the solution color of the LAMP reaction with ACBK changed from red to blue based on a decrease in the Mg2+ concentration in the reaction solution. We then optimized the LAMP with ACBK method for detecting the Cauliflower Mosaic Virus 35S promoter. Further, the specificity of the new colorimetric assay using ACBK in the LAMP reaction for detecting the 35S promoter was tested with diverse transgenic events in different crops, and the sensitivity threshold of the assay was ∼50 copies for transgenic rice genomic DNA and 100 ng of 0.1 % DNA from rice, soybean, rapeseed, and maize. Finally, the applicability of the LAMP assay was successfully validated using practical maize samples. All the detection results could be easily discerned either by UV–vis spectroscopy or the naked eye.

Virus evolves rapidly to escape vaccine-induced immunity, posing a desperate demand for efficient vaccine development biotechnologies. Here we present an express vaccine development strategy based on CRISPR/Cas9 and Cre/Lox system against re-emerging Pseudorabies virus, which caused the recent devastating swine pseudorabies outbreak in China. By CRISPR/Cas9 system, the virulent genes of the newly isolated strain were simultaneously substituted by marker genes, which were subsequently excised using Cre/Lox system for vaccine safety concern. Notably, single cell FACS technology was applied to further promote virus purification efficiency. The combination of these state-of-art technologies greatly accelerated vaccine development. Finally, vaccination and challenge experiments proved this vaccine candidate’s protective efficacy in pigs and the promise to control current pseudorabies outbreak. This is, to our knowledge, the first successful vaccine development based on gene edit technologies, demonstrating these technologies leap from laboratory to industry. It may pave the way for future express antiviral vaccine development.