Search

Hepatitis E virus (HEV) is an important cause of acute hepatitis, however, is highly neglected and largely underreported. This study aimed to describe the detailed epidemiology of hepatitis E (HE) through a 10-year surveillance. A community-based active hepatitis surveillance was conducted between November 2007 and October 2017 in 11 townships of Dongtai City in China, involving 355,673 residents. Serum samples were obtained from patients presenting with hepatitis symptoms for more than 3 days. Serum alanine aminotransferase (ALT) levels greater than 2.5 times the upper limit of normal (ULN) were considered acute hepatitis. Samples were subsequently tested for IgG and IgM anti-HEV antibodies, HEV RNA, and hepatitis B surface antigen (HBsAg). The data indicated the incidence of HE fluctuated downward from 2007 to 2017, with an average annual age-standardized incidence of 17.50 per 100,000, exceeding the 10.26 per 100,000 in the National Notifiable Disease Report System (NNDRS). The incidence was notably higher among males (20.95 per 100,000) and individuals aged 50-69 years (37.47 per 100,000). Genotype 4 (HEV-4) was the predominantly circulating genotype during the study period. Furthermore, the study revealed the incidence of hepatitis with HEV and hepatitis B virus (HBV) co-infection was 4.99 per 100,000. The active surveillance system identified a higher incidence of HE compared to NNDRS, with a decreased prevalence over a 10-year period. While efforts are still needed to prevent HE in high-risk populations, including individuals with hepatitis B and the elderly.

The emergence of Rocahepevirus ratti [species HEV ratti ( r HEV)] as a causative agent of hepatitis E in humans presents a new potential threat to global public health. The R. ratti genotype 1 ( r -1 HEV) variant only shares 50%-60% genomic identity with Paslahepevirus balayani [species HEV balayani ( b HEV)] variants, which are the main causes of hepatitis E infection in humans. Here, we report antigen diagnoses for r -1 HEV and b HEV using an enzymatic immunoassay (EIA) method. We detected recombinant virus-like particles protein (HEV 239) of r HEV and b HEV using a collection of hepatitis E virus (HEV)-specific monoclonal antibodies. Two optimal candidates, the capture antibody P#1-H4 and the detection antibodies C145 (P#1-H4*/C145 # ) and C158 (P#1-H4*/C158 # ), were selected to detect antigen in infected rat samples and r -1 HEV- or b HEV-infected human clinical samples. The two candidates showed similar diagnostic efficacy to the Wantai HEV antigen kit in b HEV-infected clinical samples. Genomic divergence resulted in low diagnostic efficacy of the Wantai HEV antigen kit (0%, 0 of 10) for detecting r -1 HEV infection. Compared with the P#1-H4*/C145 # candidate (80%, 8 of 10), the P#1-H4*/C158 # candidate had excellent diagnostic efficacy in r -1 HEV-infected clinical samples (100%, 10 of 10). The two candidates bind to a discrete antigenic site that is highly conserved across r HEV and b HEV. P#1-H4*/C145 # and P#1-H4*/C158 # are efficacious candidate antibody combinations for rat HEV antigen detection., Competing Interests: The authors declare no conflict of interest.

Objective To prepare the monoclonal antibodies specifically against P protein of human respiratory syncytial virus (HRSV) and identify it. Methods HRSV P protein prepared by prokaryotic expression in the form of overlapping peptides was used as the immunogen, and monoclonal antibodies (mAbs) were screened by hybridoma technology. Western blot analysis was used to verify the binding activity of the screened mAbs and P protein, and immunofluorescence cytochemical staining was used to determine whether the obtained mAbs could be used to detect the expression of P protein in HEp-2 cells infected with HRSV. Results P181-15A3 and P211-16D8 with great reactivity and specific recognition of HRSV P protein were screened. Both mAbs could bind to P protein by Western blot analysis and could be used for immunocytochemical detection of P protein in HEp-2 cells after HRSV infection. Conclusion We have successfully prepared the mAbs against HRSV P protein.

Respiratory syncytial virus(RSV)is a leading cause of lower respiratory tract disease. The major high risk population for RSV infection are<6month infants and elders with age older than 65 years. At present, BALB/c mice were wildly used as animal model for RSV infection, however there has no report about the comparison of different week-ages BALB/c mice after RSV infection. A different week-ages BALB/c mice model was described in this study to compare their susceptibility after RSV infection. Young(10weeks),middle aged(30weeks)and aged(60weeks)mice were intranasally infected with 106 or 107plaque-forming units (PFU) RSV, then clinical symptom, weight, RSV titer in nose/lung, histology and immunohistochemistry was examined. And age-related susceptibility was analyzed. A high-titer virus(107PFU)infection showed significant weight loss at 6-11 day post infection while 106 PFU didn’t lead to obvious weight change. In 10(7) PFU infected group, replication of virus in nose and lung was detected, the virus in lung located around pulmonary alveoli, and the hematoxylin eosin stain showed significant infiltration of inflammatory cells and pathological tissue damage. Mice trended to be more susceptible to RSV infection as the growth of age. Older mice experience more weight loss. Lung histology of older mice showed more serious bronchiolitis and increased number of inflammatory cells in alveolar spaced, and 60week-old mice tended to be the most significant. In this study, we have successfully established a different week-ages BALB/c mice model, which will serve as the basis for investigating antibody or vaccine and further infection mechanism research of RSV.

Hepatitis E, an acute self-limited disease is caused by hepatitis E virus(HEV)and is a public-health concern for people worldwide. HEV is transmitted primarily via the fecal-oral route while direct evidence for blood-borne transmission has been reported. So the risk of blood transfusion safety caused by HEV has been widely paid attention. Here, we aim to provide some references to HEV screening for blood donors through analyzing the existing diagnostic methods for HEV, which are of great significance for the prevention and control of HEV infection. Currently, the primary detection indexes for HEV primarily include HEV RNA,HEV antigen, anti-HEV IgM, and anti-HEV IgG. HEV RNA testing is considered to be the "gold standard" for the detection of HEV infection. This test takes advantage of patients with chronic Hepatitis E, immunosuppressed people, and patients with nonhepatic manifestations of hepatitis E.HEV antigen testing is regarded as a current infection index for HEV, which could be used to detect HEV in blood donors and diagnose acute HEV infection. Anti-HEV IgM is a mark of HEV recent infection, but not a single index to diagnose a current infection with HEV. Anti-HEV IgG indicates that HEV was the previous infection, and it is not suitable to diagnose acute HEV infection. At present, blood donors screening for HEV were mainly based on nucleic acid detection, and an antigen test possibly could cover its’ shortage. To confirm the value of the antigen and antibody tests for blood donor screening, further studies are required in the future.

The lack of effective in vitro infection model for hepatitis E virus (HEV) has greatly hindered the quantitative analysis of neutralizing titers of anti-HEV antibodies and human sera, thus impeding further studies of HEV-stimulated antibody responses and the immunological mechanisms. In order to improve this situation, the infection of HepG2 cells that are inefficient for HEV replication was continuously monitored until the viral load reached the limit of detection on day 13, the results of which confirmed the feasibility of using this cell line to establish the infection model. Then, neutralization assays of five anti-HEV murine monoclonal antibodies and serum samples collected from four HEV vaccine recipients (collected before and after vaccination) were performed by 96 multi-channel parallel infections, nucleic acid extraction, and qPCR. The results showed that the cell model can be applied for quantitative evaluation of the neutralizing capacity of different antibodies and antiserum samples from HEV vaccine recipients. In this study, we have successfully established a high-throughput in vitro HEV replication model, which will prove to be useful for the evaluation of HEV vaccines and studies of HEV epitopes.