Regulation of Antiviral Immunity by Mitochondrial Dynamics
Shamim I. Ahmad in Handbook of Mitochondrial Dysfunction, 2019
Classical swine fever virus (CSFV) is an enveloped RNA virus belongs to Flaviviridae family, which is associated with hepatitis C and dengue virus (Gou et al., 2017). In CSFV infected cells, oxidative stress is induced and mitochondrial transmembrane potential is disturbed. CSFV infection induces mitochondrial fission and mitophagy to inhibit host cell apoptosis (Gou et al., 2017). Expression of PINK and Parkin and their mitochondrial translocations are increased during CSFV infection. In CSFV infected cells, Mfn2 was ubiquitinated and degraded via PINK1 and Parkin pathways. During infection of CSFV, Drp1 translocation into mitochondria induces mitochondrial fission that results in mitochondrial fragmentation (Gou et al., 2017). Silencing of Drp1 and parkin during CSFV infection upregulate apoptotic signals, preserves mitochondrial proteins and reduces viral replication (Gou et al., 2017). All these events clearly indicate that mitochondrial fission and mitophagy induced by CSFV are required to increase viral persistence and cell survival.
Order Tymovirales
Paul Pumpens, Peter Pushko, Philippe Le Mercier in Virus-Like Particles, 2022
Marconi et al. (2006) fused two peptides chosen from glycoprotein E2, corresponding to aa 790–860 and aa 854–894, of classical swine fever virus (CSFV) of the Flaviviridae family of the order Amarillovirales (Chapter 22) to the N-terminus of the PVX coat via 2A peptide from FMDV and preceded by the His6 tag. The relatively long, each >40 aa residues, peptide encoding sequences were correctly retained in the PVX construct after three sequential passages in N. benthamiana plants and were replicated with high fidelity during PVX infection. The chimeric virions were able to induce an immune response in rabbits (Marconi et al. 2006).
Evaluation of a commercial enzyme-linked immunosorbent assay (ELISA) for detecting antibodies against Toxoplasma gondii from naturally and experimentally infected pigs
Published in Infectious Diseases, 2019
Giusi Macaluso, Santina Di Bella, Giuseppa Purpari, Elisabetta Giudice, Francesco Mira, Francesca Gucciardi, Anna Maria Fausta Marino, Carmelo Russo, Maria Angeles Gómez-Morales, Annalisa Guercio
One hundred and twenty seven swine serum samples were analyzed. One hundred and fifteen sera were derived from previous sampling carried out during the Italian control plans for Swine Vesicular Disease (SVD), Classical Swine Fever (CSF), Aujeszky's Disease. Twelve sera were kindly provided by the European Union Reference Laboratory for Parasites (EURLP) as reference materials; two samples originated from pig sera that tested negative for anti-Toxoplasma IgG and 10 sera originated from pigs inoculated with RH strain of T. gondii. All serum samples from experimentally infected animals were collected on day 70 (final day of experiment). From experimentally infected pig sera, three sera derived from animals which had been vaccinated with 1.2 × 105 tachizoites of the S48 strain of T. gondii and subsequently infected with 103 oocysts of the M4 strain; four sera were from animals infected with 103 oocysts of the M4 strain and three serum samples were from animals infected with 103 tissue cysts of the M4 strain. Details of the experimental infections can be found elsewhere [27]. All the serum samples were tested at the EURLP by an commercial ELISA (anti-Toxoplasma IgG, ID Screen® Toxoplasmosis Indirect Multi-species, from IDvet) and by two collaborative studies organized by the EURLP in 2015 and 2016, resulting in accordance with their assigned positivity.
Genetic engineering strategies for construction of multivalent chimeric VLPs vaccines
Published in Expert Review of Vaccines, 2020
Xinnuo Lei, Xiong Cai, Yi Yang
To elicit a high-level B cell response, foreign antigens are usually inserted into the surface exposure region of chi–VLPs [47,48], as such, the conformational location of both N/C-ter of Cap (embedded inside or facing to the surface of chi-cVLP) generally determines the feasibility and efficiency of this strategy. Currently, the most successful chi VLPs were designed and constructed with this strategy. As shown in Figure 1, N/C-ter of Cap of the four representative VLPs, HBV, HPV, PCV2, and tobacco mosaic virus (TMV) are partially exposed on the surface of cVLPs, which were able to be utilized for cVLPs development. Back in 1995, Gordon et al. fused 189 aa residues derived from P. falciparum circumsporozoite protein (CSP) to the N-ter of hepatitis B surface antigen (HBsAg). The chimeric HBsAg was expressed in yeast to produce stable chi–VLPs, referred to as RTS,S, which was later developed as the first malaria vaccine (Mosquirix®) against Plasmodium falciparum [49]. A counter example is a chi–VLP created based on PCV2, the study revealed that insertion of T-cell or B-cell epitopes of classical swine fever virus (CSFV) into the N-ter truncated PCV2 Cap failed to induce the production of neutralizing antibodies (NAbs) against CSFV [46]. The possible explanation is that N-ter of the PCV2 Cap is buried inside the cVLPs as shown in 3D structure by cryogenic electron microscopy (Cryo-EM) [50]. As a result, the inserted CSFV epitopes at the N-ter of the Cap could be hardly exposed on the surface of PCV2 cVLPs and presented to B cells that could produce NAbs.
Enhanced stability of foot-and-mouth disease vaccine antigens with a novel formulation
Published in Pharmaceutical Development and Technology, 2022
Jing Li, Rong Zhang, Huiqing Yang, Yanming Wei
Excipients, known as supplement formulated alongside the active ingredient of a medication, have been demonstrated to be effective to maintain viral structural integrity (Kim et al. 2003; Arakawa et al. 2007; Lin et al. 2021). Several classes of excipients, including carbohydrate, amino acid and metal ion are used as FMD vaccine antigen stabilizers. Carbohydrate can hydrogen bond with FMDV and then prevent dissociation, which could be explained by preferential exclusion theory (Timasheff 1993). For amino acids, such as arginine, exhibited stable effects similar to those of sugars and may therefore be considered to be an alternative excipient (Eronina et al. 2020). The use of metal ion to stabilize viral capsids has been widely reported, and the binding of CaCl2 was observed to enhance the thermostability of FMDV viral capsids (Acharya et al. 1989). The previous study showed that formulation has been applied to several virus vaccines, such as Newcastle disease (Wambura 2011), Marekʼs (Colwell et al. 1975) and Classical swine fever (Pachauri et al. 2020). Therefore, minimizing FMDV dissociation can be addressed by selecting appropriate stabilizers for formulation. In this study, we developed a novel formulation of FMDV inactivated vaccine that can provide stabilizing effect for vaccine antigen.