Group A rotaviruses (RVs) are major pathogens associated with acute gastroenteritis in young children and animals worldwide. VP4 is responsible for interaction with the host and viral attachment. Recent study showed that the distal portion of rotavirus (RV) VP4 spike protein (VP8*) is implicated in binding to human histo-blood group antigens (HBGAs), which is new cellular receptors on rotavirus, Published in Nature and Journal of Virology in 2012. The paper describes advances in correlation between rotaivrus and HBGAs, summarizes the main achievements has gotten, Clarify the significance of study on Rotaivrus and HBGAs.
Animals ; Blood Group Antigens ; genetics ; immunology ; Genetic Variation ; Humans ; Rotavirus ; immunology ; physiology ; Rotavirus Infections ; blood

Rotavirus is the leading causal agent of severe acute gastroenteritis in children aged <5 years. A specific pharmacologic agent for the treatment of rotavirus-infected children is lacking. In China, only the Luo Tewei oral vaccine (Lanzhou Institute of Biological Products, Shanghai, China), which is produced from Lanzhou lamb rotavirus vaccine (LLR), is available. Studies have hypothesized that the genotype of LLR is G10P[12], To identify the genotype of LLR by reverse transcription-polymerase chain reaction, we showed that the VP7 and VP4 genotypes of LLR were G10 and P[15], respectively, based on sequencing, alignment and phylogenetic analyses. In conclusion, we identified the genotype of rotavirus strain LLR to be G10P[15].
China ; Genotype ; Humans ; Molecular Sequence Data ; Phylogeny ; Rotavirus ; chemistry ; classification ; genetics ; isolation & purification ; Rotavirus Infections ; virology ; Rotavirus Vaccines ; chemistry ; classification ; genetics ; isolation & purification ; Sequence Homology, Amino Acid ; Viral Proteins ; chemistry ; genetics

Objective To investigate the functional and structural character of VP8 * proteins of the RV vaccine strains,VP8 * core proteins were expressed and purified.Methods The LLR RNA was extracted directly from the vaccine oral liquid,followed by RT-PCR.The VP8 * core fragment was obtained by PCR with specific primers.The full length genes of Rotateq and Rotarix VP8 * were synthesized and the VP8 * core fragments were obtained by PCR.The VP8 * core fragments were cloned to the pET30a vector respectively.The recombinant plasmids were transformed to the BL21 competent cells to do the protein expression.Then the proteins were further purified by affinity chromatography and gel filtration.The protein samples were evaluated by SDS-PAGE.Results The VP8 * core proteins were expressed in soluble form and purified and the protein bands showed at about 20 kDa in the SDS-PAGE.Conclusions The VP8 * core-pET30a plasmids were constructed and the VP8 * core proteins of the RV vaccine strains were successfully expressed and purified,which may provide the basis for the characterization of receptor binding specificity of the RV vaccine strain and the evaluation of the vaccine efficacy.

Objective To explore the binding specificity of the P[14] RV detected directly from the stool samples.Methods The P[14] VP8* protein was expressed and purified and then the binding pattern to synthetic oligosaccharides and saliva samples was carried out.Results The P[14] VP8 * protein showed significant binding to A type HBGA while almost no binding was detected to other HBGAs.Conclusions A-HBGA may be the attachment factor for the P[14] rotavirus.Therefore,the research of the interaction between P [14] RV and HBGAs provides the basis for further characterization of binding patterns of other RV genotypes and the RV surveillance.

Objective To express the VP8 * protein of the rotavirus vaccine strain LLR in the E.coli with the pGEX4T-1 vector,which is important for the further research of the VP8 * protein functions.Methods The LLR VP8 * gene was obtained by virus RNA extraction and RT-PCR.Then it was cloned in the expression vectors pGEX4T-1.The recombinant plasmid pGEX4T-1-VP8 * was transformed to the E.coli BL21.Then the VP8 *-GST fusion protein was expressed and purified by the affinity chromatograph.The protein of interest was validated by SDS-PAGE and Western Blot.Results The molecular weight of the VP8 *-GST fusion protein was about 52 000 according to the SDS-PAGE.The bands of both 52 000 and 26 000 were shown in the Western Blot with the antibody against GST.Conclusions The LLR VP8 * gene was obtained and cloned to the pGEX4T-1 vector.Moreover,the solvable VP8 *-GST fusion protein was successfully expressed and purified.

Objective:To study the binding characteristics of horse-derived P[12] rotavirus GST-VP8*-Horse P[12]E403 protein to oligosaccharides and saliva receptors, provides an important scientific basis for the cross-species transmission and the mechanism of interaction between the bodies.Methods:The E. coli expression system was used to express and purify the horse-derived P[12] rotavirus GST-VP8*-Horse P[12]E403 protein. The receptor binding characteristics of this genotype were analyzed by saliva and oligosaccharide binding experiments. Results:Horse-derived GST-VP8*-Horse P[12]E403 protein binds well with mucin core 2 sugar, but does not bind to other oligosaccharides such as A, B, Lewis, and HBGAs in saliva.Conclusions:The potential receptor of VP8*-Horse P[12]E403 protein may be mucin core 2, and it did not bind to human saliva.

Objective:To understand the epidemiological characteristics of group A rotavirus (RVA) infection in hospitalized children under 5 years of age with diarrhea in 2019, and to provide reference for the surveillance of RVA.Methods:Stool samples and clinical information of hospitalized children under 5 years of age with diarrhea were collected from sentinel hospitals in 20 provinces in 2019. RVA nucleic acid detection and genotyping were performed according to the rotavirus detection method in the National Viral Diarrhea Surveillance Program.Results:A total of 5 395 viral diarrhea samples were collected, 5 038 were tested, and 1 247 diarrhea samples showed RVA positive results (1 247/5 038, 24.75%). The positive rate of RVA in Fujian province was the lowest (30/319, 9.40%), and the positive rate of RVA was the highest in Henan province (182/338, 53.85%). The positive rate of RVA in male and female children was 25.24%(762/3 019)and 24.02%(485/ 2 019), respectively. There was no significant gender distribution of RVA infection ( χ2 = 0.96, P=0.326). Children aged 12 to 17 months were mainly susceptible to RVA (342/1 033, 33.11%), and the positive rate of RVA in children aged 48 to 59 months was lower (35/227, 15.42%). RVA infection showed significant age distribution characteristics ( χ2 = 86.78, P<0.001). RVA infection had significant difference between urban and rural areas ( χ2 = 20.92, P<0.001) and seasonal characteristics ( χ2 =411.42, P<0.001). RVA genotyping showed that G9P[8] type (994/1 122, 88.59%) was the dominant epidemic strain. Conclusions:In 2019, the main genotype of RVA infection in hospitalized children under 5 years of age with diarrhea was G9P[8], and RVA infection had significant age, region and season characteristics.

Objective:To express and purify VP7 protein of group A rotavirus (RVA) G1P[8]. The VP7 polyclonal antibody was prepared and its function was evaluated.Methods:The G1 VP7 protein was expressed by baculovirus expression system and purified by affinity chromatography. Polyclonal antibody against G1 VP7 was obtained by immunizing rabbits with G1 VP7 protein. The function of the G1 VP7 polyclonal antibody was verified by Western blotting (WB), enzyme-linked immunosorbent assay (ELISA), and immunofluorescence assay.Results:The soluble G1 VP7 protein of human RVA G1P[8] was obtained using the baculovirus expression system and the VP7 protein was mainly in trimer state. The G1 VP7 polyclonal antibody was prepared and displayed relatively high binding titer to G1 VP7 protein by ELISA. The VP7 polyclonal antibodies could recognize multiple G-type RVAs by WB and ELISA. Immunofluorescence assay further demonstrated that G1 VP7 polyclonal antibody can bind to different RVAs, including Wa (genotype G1P[8]), DS-1(genotype G2P[4]), SA11 (genotype G3P[2]), and human G9P[8] RV strains. In addition, double sandwich ELISA showed that VP7 polyclonal antibody could be used to detect rotavirus in clinical samples.Conclusions:The soluble G1 VP7 protein was successfully expressed and VP7 antibody was obtained. The G1 VP7 polyclonal antibody could bind to a variety of G-type rotaviruses, which lays a foundation for the establishment of detection method of different G type rotaviruses.

Objective: To explore the receptor binding specificity of VP8^* protein of porcine P[19] rotaviruses (RVs) with oligosaccharides. Methods: The porcine P[19] VP8^* protein was expressed and purified. The receptor binding specificity of P[19] VP8^* was analyzed by oligosaccharide binding and saliva binding assay. Results: The P[19] VP8^* protein showed significant binding to mucin cores, especially mucin core 2. Conclusions Mucin core 2 may be a potential receptor for the porcine P[19] RV, which provides certain basis for the study of virus infection mechanism and RV surveillance.

OBJECTIVE: To propose a sensitivity test method for geometric correction position deviation of cone-beam CT systems. METHODS: We proposed the definition of center deviation and its derivation. We analyzed the influence of the variation of the three-dimensional spatial center of the steel ball point, the projection center and the size of the steel ball point on the deviation of geometric parameters and the reconstructed image results by calculating the geometric correction parameters based on the Noo analytical method using the FDK reconstruction algorithm for image reconstruction. RESULTS: The radius of the steel ball point was within 3 mm. The deviation of the center of the calibration parameter was within the order of magnitude and negligible. A 10% Gaussian perturbation of a single pixel in the 3D spatial coordinates of the steel ball point produced a deviation of about 3 pixel sizes, while the same Gaussian perturbation of the 2D projection coordinates of the steel ball point produced a deviation of about 2 pixel sizes. CONCLUSION The geometric correction is more sensitive to the deviation generated by the three-dimensional spatial coordinates of the steel ball point with limited sensitivity to the deviation generated by the two-dimensional projection coordinates of the steel ball point. The deviation sensitivity of a small diameter steel ball point can be ignored.
Algorithms ; Calibration ; Cone-Beam Computed Tomography ; Steel