Expression and immunogenicity of hepatitis E virus-like particles based on recombinant truncated ORF2 capsid protein.

Hepatitis E is an emerging zoonotic disease, posing a severe threat to public health in the world. Since there are no specific treatments available for HEV infection, it is crucial to develop vaccine to prevent this infection. In this study, the truncated ORF2 encoded protein of 439aa∼617aa (HEV3-179) from HEV CCJD-517 isolates was expressed as VLPs in E. coli with diameters of approximate 20 nm. HEV3-179 protein was immunized with mice, and the results showed that a higher titre of antibody was induced in NIH mice in comparison with that of KM mice (P < 0.01) and BALB/c mice (P < 0.01). The induced antibody titer is much higher in subcutaneous immunization mice than that in the mice inoculated via abdominal immunization (P < 0.05) and muscles immunization (P < 0.01). Mice immunized with 12 µg and 6 µg candidate vaccine induced higher level of antibody titer than that of 3 µg dosage group (P < 0.01, P < 0.05). Antibody change curve showed that HEV IgG antibody titer increased from 14 days post immunization (dpi) to 1:262144 and reached the peak level on 42 dpi before gradually retreated with the same level antibody titer with 1:131072 until 84 dpi. Mice inoculated with HEV3-179 produced higher titer of cytokines than the mock group, and the concentration of IL-1ß (P < 0.01) and IFN-γ (P < 0.01) further increased after stimulated by candidate vaccine. The result indicated that HEV3-179 possesses good immunogenicity, which could be used as a potential candidate for future HEV vaccine development.

Construction of A375·S2 Melanoma Cell Line with High Sensibility to IL-1 by Overexpressing IL-1 Receptor.

We described an operation that co-overexpress interleukin receptor 1 (IL-1R1) and its co-receptor (IL-1R1AcP) genes in wild-type A375·S2 cells in order to increase their sensibility to IL-1. Firstly, laser scanning confocal microscope observed that IL-1R1 could be expressed on the surface of A375·S2 cells. qPCR was performed to estimate the ratio of two genes and result showed the ratio was almost 4.57:1. Then two genes were linked to vectors and co-transfected into A375·S2 cells. qPCR and Western blotting showed the protein content improved markedly. Finally, MTS assay was executed and the sensitivity of A375·S2 cells that co-transfected receptors to IL-1ß increased significantly. Another MTS assay showed the cell activity variation changed significantly (P < 0.05) and the reliability of the experiment was high, indicating that cell line established in this study could be further used for the activity test of IL-1Ra. Supplementary Information: The online version contains supplementary material available at 10.1007/s12088-022-01027-8.

[Nondestructive examination of tomato chilling injury by ultraweak luminescence].

Ultraweak luminescence (UWL) is an universal phenomenon of photons emission in living organism. It is intrinsically connected with biological processes, and it closely links with biochemical, physiological and pathological conditions in organisms under stress. UWL testing is widely used in clinical medicine, agriculture, environmental protection and food industry etc. But it was not applied in testing physiological disease of agricultural product in storage. This study used tomato fruit as material to find rule of UWL in fruits under chilling stress, which is the main problem in tomato fruit storage. To obtain fruits with different chilling injury degree, before cold storage a group of fruits were treated with cold shock, the effective method to decrease chilling injury, which showed alleviative chilling injury symptom compared with untreated fruits. It was found that UWL rose with the degree of chilling injury, furthermore UWL went up remarkably (P < 0.01) before symptom of chilling injury happening. Correlation analysis between UWL and chilling injury rate and chilling injury index showed that correlation coefficient was 0. 901 6 and 0.9577 (P < 0.01)respectively. In conclusion, UWL could factually reflect the degree of chilling injury.