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Abstract The mucosal immune response plays a crucial role in the prevention of respiratory viruses. Given the risk of recurrent SARS-CoV-2 infections in the population, the rapid development of next-generation intranasal COVID-19 vaccines with high safety and efficacy is paramount. In the current study, we developed a protein-based intranasal vaccine comprising the XBB.1.5 receptor binding domain (RBD)-derived trimeric recombinant protein (RBDXBB.1.5-HR) and an MF59-like oil-in-water adjuvant. Intranasal administration of RBDXBB.1.5-HR vaccine elicited robust and sustained humoral immune responses in mice and rats, resulting in high levels of neutralizing antibodies against XBB-lineage subvariants, with protection lasting for at least six months. The intranasal RBDXBB.1.5-HR vaccine generated potent mucosal immune responses, characterized by the inductions of tissue-resident T (TRM) cells, local cellular immunity, germinal center, and memory B cell responses in the respiratory tract. The combination of intramuscular and intranasal delivery of the RBDXBB.1.5-HR vaccine demonstrated exceptional systemic and mucosal protective immunity. Furthermore, intranasal delivery of RBDXBB.1.5-HR vaccine as a heterologous booster shot showed more effective boosting effects after mRNA administration compared to homologous vaccination, as evidenced by the induction of superior systemic and extra mucosal immune response. Importantly, the intranasal RBDXBB.1.5-HR vaccine conferred efficient protection against the challenge with authentic EG.5.1 viruses in vivo. These findings identify the intranasal RBDXBB.1.5-HR vaccine as a potential mucosal vaccine candidate for the prevention of SARS-CoV-2 infection.

Abstract Variants of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) continue to emerge and evade immunity, resulting in breakthrough infections in vaccinated populations. There is an urgent need for the development of vaccines with broad protective effects. In this study, we selected hotspot mutations in the receptor-binding domain (RBD) that contribute to immune escape properties and integrated them into the original RBD protein to obtain a complex RBD protein (cRBD), and we found cRBDs have broad protective effects against SARS-CoV-2 variants. Three cRBDs were designed in our study. Compared with the BA.1 RBD protein, the cRBDs induced the production of higher levels of broader-spectrum neutralizing antibodies, suggesting stronger and broader protective efficacy. In viral challenge experiments, cRBDs were more effective than BA.1 RBD in attenuating lung pathologic injury. Among the three constructs, cRBD3 showed optimal broad-spectrum and protective effects and is a promising candidate for a broad-spectrum SARS-CoV-2 vaccine. In conclusion, immunization with cRBDs triggered immunity against a wide range of variants, including those that emerged after we had completed designing the cRBDs. This study preliminarily explores and validates the feasibility of incorporating hotspot mutations that contribute to immune evasion into the RBD to expand the activity spectrum of antigen-induced antibodies.

Abstract Background Many studies have demonstrated the association between intestinal microbiota and joint diseases. The “gut-joint axis” also has potential roles in chikungunya virus (CHIKV) infection. Pro-inflammatory arthritis after CHIKV infection might disrupt host homeostasis and lead to dysbacteriosis. This study investigated the characteristics of fecal and gut microbiota, intestinal metabolites, and the changes in gene regulation of intestinal tissues after CHIKV infection using multi-omics analysis to explore the involvement of gut microbiota in the pathogenesis of CHIKV infection. Results CHIKV infection increases the systemic burden of inflammation in the GI system of infected animals. Moreover, infection-induced alterations in GI microbiota and metabolites may be indirectly involved in the modulation of GI and bone inflammation after CHIKV infection, including the modulation of inflammasomes and interleukin-17 inflammatory cytokine levels. Conclusion Our results suggest that the GI tract and its microbes are involved in the modulation of CHIKV infection, which could serve as an indicator for the adjuvant treatment of CHIKV infection. Video Abstract

Abstract Zika virus, a mosquito-borne arbovirus, has repeatedly caused large pandemics with symptoms worsening from mild and self-limiting diseases to Guillain–Barré syndrome in adults and fetal microcephaly in newborns. In recent years, Zika virus diseases have posed a serious threat to human health. The shortage of susceptible small animal models makes it difficult to study pathogenic mechanisms and evaluate potential therapies for Zika virus infection. Therefore, we chose immunocompromised mice (AG129 mice) deficient in IFN-α/β and IFN-γ receptors, which can abolish the innate immune system that prevents Zika virus infection early. AG129 mice were infected with the Zika virus, and this mouse model exhibited replication dynamics, tissue tropism, pathological lesion and immune activation of the Zika virus. Our results suggest that the inoculum dose of Zika virus can affect the viral replication dynamics, cytokine responses and survival rate in AG129 mice. By testing the potential antiviral drug favipiravir, several critical indicators, including replication dynamics and survival rates, were identified in AG129 mice after Zika virus infection. It is suggested that the model is reliable for drug evaluation. In brief, this model provides a potential platform for studies of the infectivity, virulence, and pathogenesis of the Zika virus. Moreover, the development of an accessible mouse model of Zika virus infection will expedite the research and deployment of therapeutics and vaccines.

ABSTRACTGastrointestinal (GI) infection is evidenced with involvement in COVID-19 pathogenesis caused by SARS-CoV-2. However, the correlation between GI microbiota and the distinct pathogenicity of SARS-CoV-2 Proto and its emerging variants remains unclear. In this study, we aimed to determine if GI microbiota impacted COVID-19 pathogenesis and if the effect varied between SARS-CoV-2 Proto and its variants. We performed an integrative analysis of histopathology, microbiomics, and transcriptomics on the GI tract fragments from rhesus monkeys infected with SARS-CoV-2 proto or its variants. Based on the degree of pathological damage and microbiota profile in the GI tract, five of SARS-CoV-2 strains were classified into two distinct clusters, namely, the clusters of Alpha, Beta and Delta (ABD), and Proto and Omicron (PO). Notably, the abundance of potentially pathogenic microorganisms increased in ABD but not in the PO-infected rhesus monkeys. Specifically, the high abundance of UCG-002, UCG-005, and Treponema in ABD virus-infected animals positively correlated with interleukin, integrins, and antiviral genes. Overall, this study revealed that infection-induced alteration of GI microbiota and metabolites could increase the systemic burdens of inflammation or pathological injury in infected animals, especially in those infected with ABD viruses. Distinct GI microbiota and metabolite profiles may be responsible for the differential pathological phenotypes of PO and ABD virus-infected animals. These findings improve our understanding the roles of the GI microbiota in SARS-CoV-2 infection and provide important information for the precise prevention, control, and treatment of COVID-19.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) caused the persistent coronavirus disease 2019 (COVID-19) pandemic, which has resulted in millions of deaths worldwide and brought an enormous public health and global economic burden. The recurring global wave of infections has been exacerbated by growing variants of SARS-CoV-2. In this study, the virological characteristics of the original SARS-CoV-2 strain and its variants of concern (VOCs; including Alpha, Beta, and Delta) in vitro, as well as differential transcriptomic landscapes in multiple organs (lung, right ventricle, blood, cerebral cortex, and cerebellum) from the infected rhesus macaques, were elucidated. The original strain of SARS-CoV-2 caused a stronger innate immune response in host cells, and its VOCs markedly increased the levels of subgenomic RNAs, such as N, Orf9b, Orf6, and Orf7ab, which are known as the innate immune antagonists and the inhibitors of antiviral factors. Intriguingly, the original SARS-CoV-2 strain and Alpha variant induced larger alteration of RNA abundance in tissues of rhesus monkeys than Beta and Delta variants did. Moreover, a hyperinflammatory state and active immune response were shown in the right ventricles of rhesus monkeys by the up-regulation of inflammation- and immune-related RNAs. Furthermore, peripheral blood may mediate signaling transmission among tissues to coordinate the molecular changes in the infected individuals. Collectively, these data provide insights into the pathogenesis of COVID-19 at the early stage of infection by the original SARS-CoV-2 strain and its VOCs.

Abstract Background Hepatitis E virus (HEV) infection is a common cause of acute hepatitis worldwide and causes approximately 30% case fatality rate among pregnant women. Pregnancy serum (PS), which contains a high concentration of estradiol, facilitates HEV replication in vitro through the suppression of the PI3K–AKT–mTOR and cAMPK–PKA–CREB signaling pathways. However, the proteomics of the complex host responses to HEV infection, especially how PS facilitates viral replication, remains unclear. Methods In this study, the differences in the proteomics of HEV-infected HepG2 cells supplemented with fetal bovine serum (FBS) from those of HEV-infected HepG2 cells supplemented with serum from women in their third trimester of pregnancy were quantified by using isobaric tags for relative and absolute quantification technology. Results A total of 1511 proteins were identified, among which 548 were defined as differentially expressed proteins (DEPs). HEV-infected cells supplemented with PS exhibited the most significant changes at the protein level. A total of 328 DEPs, including 66 up-regulated and 262 down-regulated proteins, were identified in HEV-infected cells supplemented with FBS, whereas 264 DEPs, including 201 up-regulated and 63 down-regulated proteins, were found in HEV-infected cells supplemented with PS. Subsequently, Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analyses revealed that in HEV-infected cells, PS supplementation adjusted more host genes and signaling pathways than FBS supplementation. The DEPs involved in virus–host interaction participated in complex interactions, especially a large number of immune-related protein emerged in HEV-infected cells supplemented with PS. Three significant or interesting proteins, including filamin-A, thioredoxin, and cytochrome c, in HEV-infected cells were functionally verified. Conclusions The results of this study provide new and comprehensive insight for exploring virus–host interactions and will benefit future studies on the pathogenesis of HEV in pregnant women.

Abstract Herd immunity achieved through mass vaccination is an effective approach to prevent contagious diseases. Nonetheless, emerging SARS-CoV-2 variants with frequent mutations largely evaded humoral immunity induced by Spike-based COVID-19 vaccines. Herein, we develop a lipid nanoparticle (LNP)-formulated mRNA-based T-cell-inducing antigen, which targeted three SARS-CoV-2 proteome regions that enriched human HLA-I epitopes (HLA-EPs). Immunization of HLA-EPs induces potent cellular responses to prevent SARS-CoV-2 infection in humanized HLA-A*02:01/DR1 and HLA-A*11:01/DR1 transgenic mice. Of note, the sequences of HLA-EPs are highly conserved among SARS-CoV-2 variants of concern. In humanized HLA-transgenic mice and female rhesus macaques, dual immunization with the LNP-formulated mRNAs encoding HLA-EPs and the receptor-binding domain of the SARS-CoV-2 B.1.351 variant (RBDbeta) is more efficacious in preventing infection of SARS-CoV-2 Beta and Omicron BA.1 variants than single immunization of LNP-RBD beta . This study demonstrates the necessity to strengthen the vaccine effectiveness by comprehensively stimulating both humoral and cellular responses, thereby offering insight for optimizing the design of COVID-19 vaccines.

Abstract Immune responses induced by severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) infection play a critical role in the pathogenesis and outcome of coronavirus disease 2019 (COVID‐19). However, the dynamic profile of immune responses postinfection by SARS‐CoV‐2 variants of concern (VOC) is not fully understood. In this study, peripheral blood mononuclear cells single‐cell sequencing was performed to determine dynamic profiles of immune response to Prototype, Alpha, Beta, and Delta in a rhesus monkey model. Overall, all strains induced dramatic changes in both cellular subpopulations and gene expression levels at 1 day postinfection (dpi), which associated function including adaptive immune response, innate immunity, and IFN response. COVID‐19‐related genes revealed different gene profiles at 1 dpi among the four SARS‐CoV‐2 strains, including genes reported in COVID‐19 patients with increased risk of autoimmune disease and rheumatic diseases. Delta‐infected animal showed inhibition of translation pathway. B cells, T cells, and monocytes showed much commonality rather than specificity among the four strains. Monocytes were the major responders to SARS‐CoV‐2 infection, and the response lasted longer in Alpha than the other strains. Thus, this study reveals the early immune responses induced by SARS‐CoV‐2 Proto or its variants in nonhuman primates, which is important information for controlling rapidly evolving viruses.

ABSTRACTMultiple clinical and epidemiological studies have shown an interconnection between coronavirus disease 2019 (COVID-19) and diabetes, but experimental evidence is still lacking. Understanding the interplay between them is important because of the global health burden of COVID-19 and diabetes. We found that C57BL/6J mice were susceptible to the alpha strain of SARS-CoV-2. Moreover, diabetic C57BL/6J mice with leptin receptor gene deficiency (db/db mice) showed a higher viral load in the throat and lung and slower virus clearance in the throat after infection than C57BL/6J mice. Histological and multifactor analysis revealed more advanced pulmonary injury and serum inflammation in SARS-CoV-2 infected diabetic mice. Moreover, SARS-CoV-2 infected diabetic mice exhibited more severe insulin resistance and islet cell loss than uninfected diabetic mice. By RNA sequencing analysis, we found that diabetes may reduce the collagen level, suppress the immune response and aggravate inflammation in the lung after infection, which may account for the greater susceptibility of diabetic mice and their more severe lung damage after infection. In summary, we successfully established a SARS-CoV-2 infected diabetic mice model and demonstrated that diabetes and COVID-19 were risk factors for one another.

The SARS-CoV-2 Omicron variant has quickly become the predominant circulating variant, due to the high transmissibility and immune escape. Here, the authors develop a trimeric protein vaccine candidate and show a sustained humoral immune response, and protection from challenge (Omicron and Delta) in various animal models.

Abstract Emerging SARS-CoV-2 variants and the gradually decreasing neutralizing antibodies over time post vaccination have led to an increase in incidents of breakthrough infection across the world. To investigate the potential protective effect of the recombinant protein subunit COVID-19 vaccine targeting receptor-binding domain (RBD) (PS-RBD) and whole inactivated virus particle vaccine (IV) against the variant strains, in this study, rhesus macaques were immunized with PS-RBD or IV vaccine, followed by a Beta variant (B.1.351) challenge. Although neutralizing activity against the Beta variant was reduced compared with that against the prototype, the decreased viral load in both upper and lower respiratory tracts, milder pathological changes, and downregulated inflammatory cytokine levels in lung tissues after challenge demonstrated that PS-RBD and IV still provided effective protection against the Beta variant in the macaque model. Furthermore, PS-RBD-induced macaque sera possessed general binding and neutralizing activity to Alpha, Beta, Delta, and Omicron variants in our study, though the neutralizing antibody (NAb) titers declined by varying degrees, demonstrating potential protection of PS-RBD against current circulating variants of concern (VOCs). Interestingly, although the IV vaccine-induced extremely low neutralizing antibody titers against the Beta variant, it still showed reduction for viral load and significantly alleviated pathological change. Other correlates of vaccine-induced protection (CoP) like antibody-dependent cellular cytotoxicity (ADCC) and immune memory were both confirmed to be existing in IV vaccinated group and possibly be involved in the protective mechanism.

Abstract Variants are globally emerging very quickly following pandemic prototypic SARS-CoV-2. To evaluate the cross-protection of prototypic SARS-CoV-2 vaccine against its variants, we vaccinated rhesus monkeys with three doses of prototypic SARS-CoV-2 inactivated vaccine, followed by challenging with emerging SARS-CoV-2 variants of concern (VOCs). These vaccinated animals produced neutralizing antibodies against Alpha, Beta, Delta, and Omicron variants, although there were certain declinations of geometric mean titer (GMT) as compared with prototypic SARS-CoV-2. Of note, in vivo this prototypic vaccine not only reduced the viral loads in nasal, throat and anal swabs, pulmonary tissues, but also improved the pathological changes in the lung infected by variants of Alpha, Beta, and Delta. In summary, the prototypic SARS-CoV-2 inactivated vaccine in this study protected against VOCs to certain extension, which is of great significance for prevention and control of COVID-19.

ABSTRACT We investigated the distribution, virulence, and pathogenic characteristics of mutated SARS-CoV-2 to clarify the association between virulence and the viral spreading ability of current and future circulating strains. Chinese rhesus macaques were infected with ancestral SARS-CoV-2 strain GD108 and Beta variant B.1.351 (B.1.351) and assessed for clinical signs, viral distribution, pathological changes, and pulmonary inflammation. We found that GD108 replicated more efficiently in the upper respiratory tract, whereas B.1.351 replicated more efficiently in the lower respiratory tract and lung tissue, implying a reduced viral shedding and spreading ability of B.1.351 compared with that of GD108. Importantly, B.1.351 caused more severe lung injury and dramatically elevated the level of inflammatory cytokines compared with those observed after infection with GD108. Moreover, both B.1.351 and GD108 induced spike-specific T-cell responses at an early stage of infection, with higher levels of interferon gamma (IFN-γ) and tumor necrosis factor alpha (TNF-α) in the B.1.351 group and higher levels of interleukin 17 (IL-17) in the GD108 group, indicating a divergent pattern in the T-cell-mediated inflammatory “cytokine storm.” This study provides a basis for exploring the pathogenesis of SARS-CoV-2 variants of concern (VOCs) and establishes an applicable animal model for evaluating the efficacy and safety of vaccines and drugs. IMPORTANCE One of the priorities of the current SARS-CoV-2 vaccine and drug research strategy is to determine the changes in transmission ability, virulence, and pathogenic characteristics of SARS-CoV-2 variants. In addition, nonhuman primates (NHPs) are suitable animal models for the study of the pathogenic characteristics of SARS-CoV-2 and could contribute to the understanding of pathogenicity and transmission mechanisms. As SARS-CoV-2 variants continually emerge and the viral biological characteristics change frequently, the establishment of NHP infection models for different VOCs is urgently needed. In the study, the virulence and tissue distribution of B.1.351 and GD108 were comprehensively studied in NHPs. We concluded that the B.1.351 strain was more virulent but exhibited less viral shedding than the latter. This study provides a basis for determining the pathogenic characteristics of SARS-CoV-2 and establishes an applicable animal model for evaluating the efficacy and safety of vaccines and drugs.

Abstract Neurological manifestations are frequently reported in the COVID-19 patients. Neuromechanism of SARS-CoV-2 remains to be elucidated. In this study, we explored the mechanisms of SARS-CoV-2 neurotropism via our established non-human primate model of COVID-19. In rhesus monkey, SARS-CoV-2 invades the CNS primarily via the olfactory bulb. Thereafter, viruses rapidly spread to functional areas of the central nervous system, such as hippocampus, thalamus, and medulla oblongata. The infection of SARS-CoV-2 induces the inflammation possibly by targeting neurons, microglia, and astrocytes in the CNS. Consistently, SARS-CoV-2 infects neuro-derived SK-N-SH, glial-derived U251, and brain microvascular endothelial cells in vitro. To our knowledge, this is the first experimental evidence of SARS-CoV-2 neuroinvasion in the NHP model, which provides important insights into the CNS-related pathogenesis of SARS-CoV-2.

Generally, biometric authentication is conducted either by mobile terminals in local-processing mode or by public servers in centralized-processing mode. In the former mode, each user has full control of his/her biometric data, but the authentication service is restricted to local mobile apps. In the latter mode, the authentication service can be opened up to network applications, but the owners have no control of their private data. It has become a difficult problem for biometric applications to provide open and trusted authentication services under user control. Existing approaches address these concerns in ad-hoc ways. In this work, we propose BioShare, a framework that provides trusted biometric authentication services to network applications while giving users full control of their biometric data. Our framework is designed around three key principles: each user has full control of his/her biometric data; biometric data is stored and processed in trusted environments to prevent privacy leaks; and the open biometric-authentication service is efficiently provided to network applications. We describe our current design and sample implementation, and illustrate how it provides an open face-recognition service with standard interfaces, combines terminal trusted environments with server enclaves, and enables each user to control his/her biometric data efficiently. Finally, we analyze the security of the framework and measure the performance of the implementation.

Hepatitis E virus (HEV) is the main pathogen of hepatitis worldwide. However, its infection biology and pathogenesis remain largely unknown. Suitable small-animal models are required to advance the study of HEV infection. Although an efficient model of genotype 1 (gt1) and gt3 HEV infection has been established in human liver chimeric mice, the infectivity of gt4 HEV infection in mice has not been comprehensively characterized. In this study, immunocompromised BALB/c nude, immunocompetent BALB/c, and C57BL/6 mice were inoculated with either gt3 or gt4 HEV (19 HEV strains, including human, swine, macaque-adapted, and cow HEV strains). Infectivity was identified by viral RNA and antigen detection, inflammation, and histopathological analysis. Then, HEV-infected BALB/c mice were treated with antiviral drugs. Acute HEV infection was established in BALB/c mice inoculated with eight gt4 HEV strains. However, gt3 HEV strains failed to achieve active HEV infection. HEV infection was established in BALB/c nude and regular mice inoculated with gt4 HEV but not in C57BL/6 mice. Gt4 HEV infection resulted in rapid viremia and high titers in feces, sera, and replication sites. HEV infection in mice showed no gender preference. Furthermore, chronic gt4 HEV infection was well imitated in BALB/c mice for 32 weeks and caused liver fibrosis.ConclusionBALB/c mice have a great potential for reproducing the process of gt4 HEV infection. The successful establishment of a gt4 HEV small-animal model provides an opportunity to further understand HEV infection biology and zoonotic transmission and develop anti-HEV vaccine.

Abstract Background Hepatitis E virus (HEV) is a leading cause of hepatitis worldwide. However, its infection biology and pathogenesis remain largely elusive. Furthermore, no proven medication is available for treating hepatitis E. Robust experimental models are urgently required to advance the research of HEV infection. Because of the lacking of a sophisticated small animal model, this study aimed to establish a mouse model of HEV infection. Methods We constructed a full-length swine HEV cDNA clone of genotype 4 (named as pGEM-HEV) by reverse genetics approach. And we inoculated with HEV RNA in BALB/c mice to establish small animal model for HEV infection and pathogenesis studies. Results The capped RNA transcripts of pGEM-HEV prepared in vitro were replication-competent in HepG2 cells. Importantly, BALB/c mice intravenously inoculated with RNA transcripts of pGEM-HEV developed an active infection as shown by shedding viruses in feces, detectable negative strand of HEV in the liver, spleen and kidney, and causing liver inflammation. Conclusion In this study, we successfully established of BALB/c mice-based small animal model for HEV provides an opportunity to further understand HEV pathogenesis and to develop effective antiviral medications.

To evaluate whether uterine injury caused by hepatitis E virus (HEV) infection is responsible for adverse pregnancy outcomes. HEV-infected female BALB/c mice were coupled with healthy male BALB/c mice at 0, 7, 14, 21, and 91 dpi to explore the uterine injury caused by HEV infection. Mice were euthanized after 10 days of copulation, and uteruses were collected for HEV RNA and antigen detection and histopathological analysis. Inflammatory responses; apoptosis; and estrogen receptor ɑ (ER-ɑ), endomethal antibody (ERAb), cytokeratin-7 (CK7), vimentin (VIM), and vascular endothelial growth factor (VEGF) expression levels were evaluated. After 10 days of copulation, miscarriage and nonpregnancy, as well as enlarged uteruses filled with inflammatory cytokines, were found in HEV-infected mice. HEV RNA and antigens were detected in the sera and uteruses of HEV-infected mice. Significant endometrial thickness (EMT) thinning, severe inflammatory responses, and aggravated apoptosis in the uteruses of HEV-infected mice that experienced miscarriage might contribute to adverse pregnancy outcomes. Furthermore, significantly suppressed ER-ɑ expression and increased ERAb, CK7, VIM, and VEGF expression levels were found in the uteruses of HEV-infected mice that had miscarried. However, uterine damage recovered after complete HEV clearance, and impaired fertility was improved. EMT injury, severe inflammatory responses, and aggravated apoptosis in the uterus caused by HEV infection are responsible for poor pregnancy outcomes.

Rhesus macaque is an important animal model in biomedical research, especially human disease, developmental, translational, and pre-clinical research. Blood physiological and biochemical parameters are important markers for physiology, pathology, and toxicology research. However, these parameters have not been systematically reported for Chinese rhesus macaques. To characterize the reference for these parameters, this study collected 1805 Chinese rhesus macaques living in Southwestern China. A total of 24 blood physiological indexes and 27 biochemical parameters were determined. Sex and age were found to affect these parameters. In conclusion, a comprehensive and systematic reference of hematological and biochemical parameters for Chinese rhesus macaque was established in this work on the basis of a large cohort. Such reference will benefit biomedical research employing rhesus macaques as animal models.

Worldwide, the Hepatitis E virus (HEV) is the main pathogen of acute viral hepatitis, with an extremely high mortality in pregnant women. However, the pathogenesis of HEV infection in pregnant women remains largely unknown. We established an HEV-infected pregnant mice animal model to explore the adverse pregnancy outcomes of HEV infection. Mice were infected with HEV in their early, middle and late stages of pregnancy. HEV RNA was detected in the tissues (liver, spleen, kidney, colon, uterus and placenta) of pregnant mice. HEV antigens were also detected in these tissues of HEV-infected pregnant mice. Miscarriages (7/8, 87.5%) occurred in pregnant mice infected with HEV in the middle of pregnancy. Th1-biased immune status was found in these aborted mice. Vertical transmission was confirmed by HEV replication in the uterus and placenta, as well as in the positive HEV RNA and HEV antigen positive in fetal livers. The successful establishment of HEV infection in pregnant mice is beneficial for further study of HEV pathogenesis, especially the adverse pregnancy outcomes caused by HEV infection.

As one of the major pathogens for human herpetic diseases, herpes simplex virus type 1 (HSV1) causes herpes labialis, genital herpes and herpetic encephalitis. Our aim here was to investigate the infectious process of HSV1 in rhesus macaques and the pathological features induced during this infection. Clinical symptoms that manifested in the rhesus macaque during HSV1 infection included vesicular lesions and their pathological features. Viral distribution in the nervous tissues and associated pathologic changes indicated the typical systematic pathological processes associated with viral distribution of HSV1.Interestingly, vesicular lesions recurred in oral skin or in mucosa associated with virus shedding in macaques within four to five months post‐infection,and viral latency‐associated transcript (LAT) mRNA was found in the trigeminal ganglia (TG)on day 365 post‐infection. Neutralization testing and enzyme‐linked immunospot (ELISpot) detection of specific T cell responses confirmed the specific immunity induced by HSV1 infection. Thus, rhesus macaques could serve as an infectious model for HSV1 due to their typical clinical symptoms and the pathological recurrence associated with viral latency in nervous tissues.