Positive regulation of humoral and innate immune responses induced by inactivated Avian Influenza Virus vaccine in broiler chickens

Effect of Wei Qi Booster on immune and anti-oxidative function in aged mice

This research was conducted to examine the impact of Wei Qi Booster (WQB) on immune parameters and anti-oxidative function in aged mice. Fifty aged mice were randomly assigned to five different groups. Group A was designated as the control group. Mice in Group B were receiving Levamisole at 10 mg/kg body weight. Each mouse in groups C, D and E received 0.1, 1, and 2% WQB, respectively. Another ten young mice, designated as group F, were fed regularly. The mice were fed according to the above methods for 28 days. Results showed that relative to the control group, the body weight and immune organs indexes experienced a substantial rise in the group with 1% WQB. In addition, 1% WQB could improve the activity of SOD and reduce the MDA levels. Expressions of CD4 and sIgA increased while CD8 decreased in the jejunum of aged mice treated with WQB. IL2 and IFN-γ levels increased in the 1% WQB group, showing no notable difference compared to the young mice group. The results demonstrated that WQB can elevate immune levels and enhance anti-oxidative functions in aged mice.

Effects of saponins Rb1 and Re in American ginseng combined intervention on immune system of aging model

Aging is a major risk factor for the development of many pathological processes, such as reduced immunity, cancer, cardiovascular diseases or neurodegenerative diseases, while age-related chronic diseases are the most common causes of death. This paper studies the effects of American ginseng saponin Rb1 and Re alone and combined intervention on the immune system of aging mouse models, by using 30 mg/kg Rb1, 15 mg/kg Re, and Rb1 + Re (30 mg/kg Rb1 and 15 mg/kg Re (co-intervention) was used to intervene in the aging model, and immune indicators such as thymus index, spleen index, interleukin and interferon were detected to evaluate the impact of Rb1 and Re on immune function. The results show that Rb1 and Re intervention alone can increase the spleen index by 7%-12% and the thymus index by 12%-19% in the aging model. After Rb1 or Re alone intervened, the apoptotic cells in the thymus were slightly reduced, and the proportion of apoptotic cells was reduced. The combination of Rb1 + Re can promote the thymus index and spleen index to increase by 23.40% and 25.5% respectively, which is more advantageous than Rb1 or Re alone. In addition, Rb1 and Re intervention can reduce the level of interferon INF to a level comparable to that of young mice. Rb1 + Re can not only reduce the INF content, but also reduce the TNF content. The above results show that American ginseng saponin Rb1 and Re can delay the decline of the immune system in the aging model, and the combined intervention of the two is significantly better than individual intervention in the recovery of the immune system. This paper can provide theoretical basis and data support for the development of American ginseng nutritional supplements and its application in aging groups products to improve immunity.

Dynamic Changes in the Expression of Interferon-Stimulated Genes in Joints of SPF Chickens Infected With Avian Reovirus

Avian reovirus (ARV) can induce many diseases as well as immunosuppression in chickens, severely endangering the poultry industry. Interferons (IFNs) play an antiviral role by inducing the expression of interferon-stimulated genes (ISGs). The effect of ARV infection on the expression of host ISGs is unclear. Specific-pathogen-free (SPF) chickens were infected with ARV strain S1133 in this study, and real time quantitative PCR was used to detect changes in the dynamic expression of IFNs and common ISGs in joints of SPF chickens. The results showed that the transcription levels of IFNA, IFNB, and several ISGs, including myxovirus resistance (MX), interferon-induced transmembrane protein 3 (IFITM3), protein kinase R (PKR), oligoadenylate synthase (OAS), interferon-induced protein with tetratricopeptide repeats 5 (IFIT5), interferon-stimulated gene 12 (ISG12), virus inhibitory protein (VIPERIN), interferon-alpha-inducible protein 6 (IFI6), and integrin-associated protein (CD47), were upregulated in joints on days 1–7 of infection (the levels of increase of MX, IFIT5, OAS, VIPERIN, ISG12, and IFI6 were the most significant, at hundreds-fold). In addition, the expression levels of the ISGs encoding zinc finger protein 313 (ZFP313), and DNA damage–inducible transcript 4 (DDIT4) increased suddenly on the 1st or 2nd day, then decreased to control levels. The ARV viral load in chicken joints rapidly increased after 1 day of viral challenge, and the viral load remained high within 6 days of viral challenge. The ARV viral load sharply decreased starting on day 7. These results indicate that in SPF chicken joints, many ISGs have mRNA expression patterns that are basically consistent with the viral load in joints. IFNA, IFNB, and the ISGs MX, IFITM3, PKR, OAS, IFIT5, ISG12, VIPERIN, IFI6, and CD47 play important roles in defending against ARV invasion, inhibiting ARV replication and proliferation, and promoting virus clearance. These results enrich our understanding of the innate immune response mechanisms of hosts against ARV infection and provide a theoretical basis for prevention and control of ARV infection.

Different kinetics of chicken interferon-alpha signalling transduction responses following immunization of broiler chickens with different Newcastle disease virus vaccines and infection with virulent genotype VIId strain

Newcastle disease virus (NDV) is a highly contagious and notifiable avian disease leading to grave economic losses in the poultry industry. Although the immune responses against NDV have been widely investigated, little is known regarding the virus interaction with the host innate immune responses. In this study, we tested the effect of different commercially applied Newcastle disease vaccines as well as virulent NDV genotype VIId on the expression pattern of the upstream regulator and downstream effector genes related to chicken interferon-alpha (chIFNα) signalling transduction pathway. Using quantitative real-time PCR analysis, mild transient induction of chIFNα-inducible genes was detected in bird spleen 72 h post-vaccination (hpv) with either live LaSota (respiratory) or VG/GA (enteric) strains. Vaccination with the enteric VG/GA strain led to stimulation of the investigated pathway as early as 24 hpv which continued up to 7 days in bird caecal tonsils. Subcutaneous injection with inactivated LaSota oil adjuvant-based vaccine led to continual stimulation of the investigated pathway up to 7 days post-vaccination (dpv). The recombinant herpesvirus of turkey (rHVT) - NDV vaccine led to remarkable stimulation of all the tested cytokines up to 17 dpv in comparison with LaSota and VG/GA NDV vaccines. Stronger but transient activation of all the tested cytokines was detected in spleens during the first 24 h post-challenge with virulent NDV (vNDV) which reduced gradually and diminished later due to the virus-induced lymphocytic depletion. This study will aid in the discovery of new approaches to control NDV.

Bone marrow mesenchymal stem cells improve thymus and spleen function of aging rats through affecting P21/PCNA and suppressing oxidative stress

Bone marrow mesenchymal stem cells (BMSCs) have been considered to be an important regulator for immune function. We aim to prove the function improvement of aging spleen and thymus induced by BMSCs and unfold the specific mechanisms. Aging animal model was established using D-galactose. The morphological changes of spleen and thymus tissues were observed using hematoxylin-eosin staining and transmission electron microscopy. Key cytokines in the serum were measured with enzyme linked immunosorbent assay. Protein and mRNA levels of P16, P21, and PCNA were detected using western blotting and RT-qPCR. Special markers of BMSCs were identified using flow cytometry, and successful induction of BMSCs to steatoblast and osteoblasts was observed. Compared to aging model, BMSCs significantly increased the spleen and thymus index, improved the histological changes of spleen and thymus tissues. A remarkable increase of ratio between CD4+T cells and CD8+T cells, level of IL-2 was achieved by BMSCs. However, BMSCs markedly inhibited the content of IL-10, TNF-a, P16, and P21 but promoted PCNA. Significant inhibition of oxidative stress by BMSCs was also observed. We demonstrated that BMSCs significantly improved the tissue damage of aging spleen and thymus, BMSCs may improve aging organs through influencing cytokines, oxidative stress, and P21/PCNA.

Influence of Marek's disease virus vaccines on chicken melanoma differentiation-associated gene 5-dependent-type I interferon signal transduction pathway with a highlight on their secondary impact on the immune responses post Newcastle disease virus vaccination

Marek's disease virus (MDV) leads to a lytic infection of B-lymphocytes in chickens, and also latently infects T-lymphocytes. Although Marek's disease vaccines have been widely in use, little is known about the innate immune response of this important livestock vaccine. In this study, we tested the effect of different commercially applied Marek's disease vaccines on the expression pattern of selected genes related to chicken interferon-alpha (chIFN-α) (melanoma differentiation associated gene 5 "MDA5″ dependent) signal transduction pathway. Both MDV serotype I (Rispens) and serotype III (Herpesvirus of turkey "HVT") vaccines could stimulate MDA5 dependent-type I interferon response as early as three days post vaccination in a dose-dependent manner. The stimulation continued up to 10 days in the instance of HVT vaccine and declined in the case of Rispens. Surprisingly, increasing the doses of the two vaccines led to dose-dependent down-regulation in the expression pattern of the investigated pathway, five and ten days post vaccination. Additionally, to shed the light on the consequent effect on the immune responses of the other viral vaccine, another experimental model based on Newcastle disease virus (NDV) vaccines was designed using HVT, HVT-VP2 and Rispens MDV vaccines. The three MDV vaccines were found to reduce chicken humoral immune response post NDV vaccination. However, only Rispens and HVT-VP2 had suppressive effects on the expression of MDA5-dependent-chIFN-α related cytokines. Consistent with this finding, the protection rate and NDV- humoral immune response post challenge with virulent NDV strain was lower in case of Rispens and HVT-VP2 vaccines.

Altered gene expression profiles of the MDA5 signaling pathway in peripheral blood lymphocytes of chickens infected with avian reovirus

Avian reovirus (ARV) is a member of the genus Orthoreovirus in the family Reoviridae and causes a severe syndrome including viral arthritis that leads to considerable losses in the poultry industry. Innate immunity plays a significant role in host defense against ARV. Here, we explored the interaction between ARV and the host innate immune system by measuring mRNA expression levels of several genes associated with the MDA5 signaling pathway. The results showed that expression peaks for MDA5, MAVS, TRAF3, TRAF6, IRF7, IKKɛ, TBK1 and NF-κB occurred at 3 days postinfection (dpi). Moreover, type I IFN (IFN-α, IFN-β) and IL-12 expression levels peaked at 3 dpi, while type II IFN (IFN-γ), IL-6, IL-17 and IL-18 expression reached a maximum level at 1 dpi. IL-8 changed at 5 dpi, and IL-1β and TNF-α changed at 7 dpi. Interestingly, several key IFN-stimulated genes (ISGs), including IFITM1, IFITM2, IFITM5, Mx1 and OASL, were simultaneously upregulated and reached maximum values at 3 dpi. These data indicate that the MDA5 signaling pathway and innate immune cytokines were induced after ARV infection, which would contribute to the ARV-host interaction, especially at the early infection stage.

Effectiveness of different avian influenza (H5) vaccination regimens in layer chickens on the humoral immune response and interferon-alpha signalling immune marker

Avian influenza (AI) vaccines are widely used to control and eliminate the ongoing avian influenza virus epidemic in Egypt. A strict vaccination policy with inactivated AI vaccines has been widely applied, however the virus still circulating, evolving and causing great negative impact to the poultry sector in Egypt. Therefore, an updated poultry vaccination policy using different vaccine technologies might be valuable as an innovative additional control strategy of AIV in Egypt. In the present study, the effectiveness of different avian influenza (AI) vaccination schedules was evaluated in 300 commercial layer chicks (ISA White) using either the oil-emulsion baculovirus-H5-prototype vaccine (baculovirus-H5 prototype) or turkey herpesvirus (HVT) vector vaccine containing the hemagglutinin (HA) gene from H5N1 strain (rHVT-H5), applied alone or in combination and in different settings. Vaccination with either two injections of the baculovirus-H5 prototype, a single injection of rHVT-H5 or priming with rHVT-H5 at 1 day old followed by boosting with the baculovirus-H5 prototype induced AI-HI protective antibody responses starting as early as 3 to 4 weeks of age and lasting up to the end of the rearing period (16 weeks). A single vaccination with the baculovirus-H5 prototype did not generate a protective antibody titre for the entire rearing period. Furthermore, the present study elucidated that vaccination once or twice with the baculovirus-H5 vaccine prototype activated the chicken interferon-alpha (Ch-IFN-alpha) signalling pathway via transduction of antiviral components, e.g., Mx1 and IRF7. Birds immunized once with rHVT-H5 at 1 day old did not show activation of the Mx1 and IRF7 transcripts; however, following boosting with the baculovirus-H5 prototype vaccine, up-regulation of Mx1 and IRF7 was observed. Based on our findings, it can be concluded that either reinforcement with two injections of the baculovirus-H5 prototype or prime-boost vaccination (rHVT-H5 at 1 day old followed by the baculovirus-H5 prototype vaccine at 8 days old) is a successful strategy to induce both innate and humoral immune responses and could be recommended for the layer production sector over the entire rearing period, especially in AI-endemic areas.