Viremia in Equine Herpes Virus-1 infection and a possible link to Transient Protective Immunity

Equine herpes virus (EHV-1) causes respiratory infections in equine, and results in abortion, paresis, neonatal death, and retinopathy and the virus may become latent following initial infection. Virus entry is via the respiratory route, and the virus replicates in the host in ciliated and non-ciliated epithelial cells of the respiratory tract and in Type 1 and Type 2 pneumocytes in the lung parenchyma. After viral replication in the respiratory system, the virus can become disseminated to other parts of body via viraemic cells. The virus also can cross the placenta which leads to abortion of live or dead fetuses without premonitory signs. Infected horses show transient immunity after natural or experimental infection and immune responses to EHV-1, but the immunoprotective status begins to decline after a few months of active infection. Due to the transient immune response, recovered horses are not immunoprotected and thus are prone to subsequent re-infection. Immunity is not long lived after experimental or natural infection, and as a result the development of an effective vaccine has remained a challenge. In this study viraemic cells were studied in a murine EHV-1 infection model. Mice were infected intranasally and viraemic cells were studied on days three and five which occurs during the peak of the infection. The results of this study may help to identify the nature of viraemic cells and their role in the transient immune response to infection. Buffy coat cells and lungs were removed and stained with a fluorescent antibody test for EHV-1 antigen, and lung specimens were subjected to transmission electron microscopy. Both techniques confirmed the presence of viraemic cells in lung tissues. These viraemic cells were further stained for EHV-1 antigen, and for CD4 or CD8 biomarkers and results are discussed re: pathogenesis of EHV-1 infection, identification of viraemic cells in a murine model and possible link of viraemia to transient immune responses in EHV-1 infection, which demonstrate the validity of this murine model for the investigation of the cytopathologic mechanism and sequelae of EHV manifestation in this model.

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The Sp1-Responsive microRNA-15b Negatively Regulates Rhabdovirus-Triggered Innate Immune Responses in Lower Vertebrates by Targeting TBK1

Frontiers in Immunology ◽

10.3389/fimmu.2020.625828 ◽

2021 ◽

Vol 11 ◽

Author(s):

Renjie Chang ◽

Qing Chu ◽

Weiwei Zheng ◽

Lei Zhang ◽

Tianjun Xu

Keyword(s):

Immune Response ◽

Immune Responses ◽

Innate Immune ◽

Infection Model ◽

Regulation Mechanism ◽

Type I ◽

Innate Immune Responses ◽

Positive Role ◽

Siniperca Chuatsi ◽

Antiviral Immune Response

As is known to all, the production of type I interferon (IFN) plays pivotal roles in host innate antiviral immunity, and its moderate production play a positive role in promoting the activation of host innate antiviral immune response. However, the virus will establish a persistent infection model by interfering with the production of IFN, thereby evading the organism inherent antiviral immune response. Therefore, it is of great necessity to research the underlying regulatory mechanisms of type I IFN appropriate production under viral invasion. In this study, we report that a Sp1–responsive miR-15b plays a negative role in siniperca chuatsi rhabdovirus (SCRV)-triggered antiviral response in teleost fish. We found that SCRV could dramatically upregulate miiuy croaker miR-15b expression. Enhanced miR-15b could negatively regulate SCRV-triggered antiviral genes and inflammatory cytokines production by targeting TANK-binding kinase 1 (TBK1), thereby accelerating viral replication. Importantly, we found that miR-15b feedback regulates antiviral innate immune response through NF-κB and IRF3 signaling pathways. These findings highlight that miR-15b plays a crucial role in regulating virus–host interactions, which outlines a new regulation mechanism of fish’s innate immune responses.

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Robust SARS-CoV-2-specific T-cell immunity is maintained at 6 months following primary infection

10.21203/rs.3.rs-101480/v1 ◽

2020 ◽

Author(s):

Jianmin Zuo ◽

Alex Dowell ◽

Hayden Pearce ◽

Kriti Verma ◽

Heather Long ◽

...

Keyword(s):

Immune Response ◽

T Cell ◽

Immune Responses ◽

Antibody Level ◽

Primary Infection ◽

Natural Infection ◽

T Cell Responses ◽

Symptomatic Infection ◽

Cell Responses ◽

Cell Immunity

Abstract The immune response to SARS-CoV-2 is critical in both controlling primary infection and preventing re-infection. However, there is concern that immune responses following natural infection may not be sustained and that this may predispose to recurrent infection. We analysed the magnitude and phenotype of the SARS-CoV-2 cellular immune response in 100 donors at six months following primary infection and related this to the profile of antibody level against spike, nucleoprotein and RBD over the previous six months. T-cell immune responses to SARS-CoV-2 were present by ELISPOT or ICS analysis in all donors and are characterised by predominant CD4+ T cell responses with strong IL-2 cytokine expression. Median T-cell responses were 50% higher in donors who had experienced an initial symptomatic infection indicating that the severity of primary infection establishes a ‘setpoint’ for cellular immunity that lasts for at least 6 months. The T-cell responses to both spike and nucleoprotein/membrane proteins were strongly correlated with the peak antibody level against each protein. The rate of decline in antibody level varied between individuals and higher levels of nucleoprotein-specific T cells were associated with preservation of NP-specific antibody level although no such correlation was observed in relation to spike-specific responses. In conclusion, our data are reassuring that functional SARS-CoV-2-specific T-cell responses are retained at six months following infection although the magnitude of this response is related to the clinical features of primary infection.

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SARS-CoV-2 Serology Status Detected by Commercialized Platforms Distinguishes Previous Infection and Vaccination Adaptive Immune Responses

10.1101/2021.03.10.21253299 ◽

2021 ◽

Author(s):

Raymond T. Suhandynata ◽

Nicholas J. Bevins ◽

Jenny T. Tran ◽

Deli Huang ◽

Melissa A. Hoffman ◽

...

Keyword(s):

Immune Response ◽

Immune Responses ◽

Neutralizing Antibodies ◽

Natural Infection ◽

Adaptive Immune Response ◽

Antibody Assay ◽

Adaptive Immune Responses ◽

Adaptive Immune ◽

Previous Infection ◽

A Cell

AbstractBackgroundThe severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has infected over 110 million individuals and led to 2.5 million deaths worldwide. As more individuals are vaccinated, the clinical performance and utility of SARS-CoV-2 serology platforms needs to be evaluated.MethodsThe ability of four commercial SARS-CoV-2 serology platforms to detect previous infection or vaccination were evaluated using a cohort of 53 SARS-CoV-2 PCR-positive patients, 89 SARS-CoV-2-vaccinated healthcare workers (Pfizer or Moderna), and 127 SARS-CoV-2 negative patients. Serology results were compared to a cell based SARS-CoV-2 pseudovirus (PSV) neutralizing antibodies assay.ResultsThe Roche S-(spike) antibody and Diazyme neutralizing antibodies (NAbs) assays detected adaptive immune response in 100.0% and 90.1% of vaccinated individuals who received two-doses of vaccine (initial and booster), respectively. The Roche N-(nucleocapsid) antibody assay and Diazyme IgG assay did not detect adaptive immune response in vaccinated individuals. The Diazyme Nabs assay correlated with the PSV SARS-CoV-2 ID50 neutralization titers (R2= 0.70), while correlation of the Roche S-antibody assay was weaker (R2= 0.39). Median PSV SARS-CoV-2 ID50 titers more than doubled in vaccinated individuals who received two-doses of the Moderna vaccine (ID50: 597) compared to individuals that received a single dose (ID50: 284).ConclusionsThe Roche S-antibody and Diazyme NAbs assays robustly detected adaptive immune responses in SARS-CoV-2 vaccinated individuals and SARS-CoV-2 infected individuals. The Diazyme NAbs assay strongly correlates with the PSV SARS-CoV-2 NAbs in vaccinated individuals. Understanding the reactivity of commercially available serology platforms is important when distinguishing vaccination response versus natural infection.SummaryThe Roche S (spike protein)-antibody and Diazyme neutralizing-antibodies (NAbs) assays were evaluated for their clinical utility in the detection of SARS-CoV-2 related adaptive immune responses by testing SARS-CoV-2 PCR-confirmed patients, SARS-CoV-2-vaccinated individuals, and SARS-CoV-2-negative individuals. Commercial serology results were compared to results generated using a cell-based SARS-CoV-2 pseudovirus (PSV) NAbs assay and previously validated SARS-CoV-2 commercial serology assays (Roche N (nucleocapsid protein) antibody and Diazyme IgG). We demonstrate that the Roche S-antibody and Diazyme NAbs assays detected adaptive immune response in SARS-CoV-2 vaccinated individuals and the presence of SARS-CoV-2 PSV NAbs. The Roche S-antibody assay had an observed positive percent agreement (PPA) of 100% for individuals who received two doses of the Pfizer or Moderna vaccine. By contrast, the Roche N assay and Diazyme IgG assay did not detect vaccine adaptive immune responses. Our findings also indicate that the Diazyme NAbs assay correlates strongly with the levels of SARS-CoV-2 ID50 neutralization titers using the PSV Nab assay in vaccinated individuals.

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306. Cytokine Secreting Oncolytic Herpes Virus Effectively Treats Micrometastatic Liver Disease in a Murine Model

Molecular Therapy ◽

10.1016/s1525-0016(16)43136-9 ◽

2002 ◽

Vol 5 (5) ◽

pp. S101-S102

Keyword(s):

Liver Disease ◽

Murine Model ◽

Herpes Virus ◽

Herpès Virus

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The state of cellular immunity of patients with tonsillitis and infected with herpes virus type 6

Problems of Uninterrupted Medical Training and Science ◽

10.31071/promedosvity2021.01.077 ◽

2021 ◽

Vol 41 (1) ◽

pp. 77-81

Author(s):

V. M. Olkhovska ◽

Keyword(s):

Immune Response ◽

Cellular Immunity ◽

Herpes Virus ◽

Maximum Growth ◽

Complete Recovery ◽

Cellular Component ◽

The State ◽

Streptococcus Group ◽

Herpès Virus ◽

Herpes Group

Currently, the incidence of tonsillitis in children is very common and represents a serious medical and social problem. In young children, viral tonsillitis predominates, while bacterial tonsillitis is more common between the ages of 5–15. The frequency of registration of infection with viruses of the herpes group, including the human herpes virus (HHV) type 6, is increasing. The healing processes in infectious pathology are primarily due to the balanced work of the cellular and humoral links of the body’s immune response, the state of which can be influenced by concomitant infection with herpes viruses. The aim of the work was to study the cellular immune response of children with tonsillitis infected with HHV-6 type. The study of the influence of HHV-6 infection on the state of the cellular component of the immune response in 74 children with tonsillitis in the acute period and in the period of convalescence was carried out. All patients were diagnosed with a moderate form of tonsillitis; the etiological factor was hemolytic streptococcus group A. It was revealed that in children with mono-infection at the onset of the disease, there is a moderate response of cellular immunity (t = 2.76), while the presence of HHV-6 infection leads to more pronounced changes in the parameters of CD lymphocytes (t = 4.06). We found a significant increase in the content of CD16+-lymphocytes in tonsillitis of streptococcal etiology, but the maximum growth was recorded in patients with mono-infection (p < 0.05). By the time of convalescence, complete recovery of T-lymphocytes in infected HHV-6 patients does not occur. The degree of deviation from the standard for the entire complex of CD-lymphocytes during the period of convalescence was more pronounced in patients with co-infection (t = 2.83). The obtained data indicate the suppression of the cellular component of the immune response in patients with tonsillitis against the background of HHV-6 infection, which requires a differentiated approach to treatment and medical supervision of such patients.

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Stress induced by agression modifies the mortality and the immune response to Herpes virus (HSV1) challenge in BALB/C mice

Journal of Neuroimmunology ◽

10.1016/0165-5728(87)90216-5 ◽

1987 ◽

Vol 16 (1) ◽

pp. 57

Author(s):

M.H. François ◽

D. Viza ◽

P. Roubertoux ◽

J. Phillips

Keyword(s):

Immune Response ◽

Herpes Virus ◽

Herpès Virus

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Experimental Staphylococcus aureus Mastitis Infection Model by Teat Dipping in Bacterial Culture Suspension in Dairy Cows

Animals ◽

10.3390/ani10050751 ◽

2020 ◽

Vol 10 (5) ◽

pp. 751

Author(s):

Oudessa Kerro Dego ◽

Paulina A. Pacha ◽

Barbara E. Gillespie ◽

Gina M. Pighetti

Keyword(s):

Staphylococcus Aureus ◽

Dairy Cows ◽

Natural Infection ◽

Effective Vaccine ◽

Bacterial Suspension ◽

Infection Model ◽

Culture Suspension ◽

Physical Barriers ◽

And Control ◽

Teat Dipping

Mastitis is inflammation of mammary glands usually caused by bacteria such as Staphylococcus aureus. Dairy cows are susceptible to mastitis during early dry and transition periods. Effective vaccine is needed during these periods. One of the limitations to develop an effective vaccine against S. aureus is the absence of good infection model. Intramammary infusion (IMIF) with S. aureus has been used as an infection model to test vaccine efficacy. IMIF is reliable in causing mastitis, but it bypasses physical barriers, non-specific natural defenses, and immunity in the teat canal. IMIF also transfers a large number of bacteria into the intramammary area at once. The objective of this study was to develop S. aureus IMIF model that mimics natural infection. Eight Holstein dairy cows were randomly divided into two groups of experimental (n = 5) and control (n = 3) cows. All teats of experimental cows were dipped in S. aureus culture suspension, whereas that of control cows were dipped in phosphate-buffered saline. Results showed that four of five cows were infected with challenge strain by day 3 of the challenge. The remaining cow was infected with Staphylococcus chromogenes. In conclusion, an experimental S. aureus intramammary infection can be induced by teat dipping into bacterial suspension.

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Evaluation of Lsa46 and Lsa77 Leptospiral Proteins for Their Immunoprotective Activities in Hamster Model of Leptospirosis

BioMed Research International ◽

10.1155/2018/1813745 ◽

2018 ◽

Vol 2018 ◽

pp. 1-13 ◽

Cited By ~ 1

Author(s):

Aline F. Teixeira ◽

Luis G. V. Fernandes ◽

Antonio Souza Filho ◽

Gisele O. Souza ◽

Silvio A. Vasconcellos ◽

...

Keyword(s):

Immune Response ◽

Immune Responses ◽

Protective Immunity ◽

Effective Vaccine ◽

Neglected Tropical Disease ◽

Bacterial Burden ◽

Hamster Model ◽

Vaccine Candidates ◽

Sterilizing Immunity

Leptospirosis is a neglected tropical disease caused by pathogenicLeptospiraspp. The lack of an effective vaccine favors the increase of the disease. Currently, surface-exposed proteins are the main targets for the search of vaccine candidates. In this study, we examined whether the surface Lsa46 and Lsa77 proteins, previously identified as laminin and plasminogen binding proteins, have the capacity of inducing protection and sterilizing immunity against challenge with virulentLeptospirain hamster model. Animals were subcutaneously immunized with Lsa46, Lsa77, or a combination of both in Alum adjuvant and challenged intraperitoneally withL. interrogansserovar Kennewicki strain Pomona Fromm. Hamster immunization with Lsa46 or Lsa77 or both promoted a strong IgG response. Th2- and Th1-biased immune responses were observed when Lsa46 and Lsa77 were individually administered, respectively, as detected by the IgG1/IgG2/3 ratio. Immunized hamsters with the combined proteins induced a Th1-biased immune response. Although the immunization with Lsa46 and Lsa77 stimulated protective immunity with reduction of bacterial burden, when compared to animals individually immunized with the proteins, the data was not statistically significant. Thus, although promising, more studies are needed before the role of these proteins in stimulating sterilizing immunity in mammals is conclusively determined.

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