ABSTRACT
The cross-species transmissibility of SARS-CoV-2 infection has necessitated development of specific reagents for detecting infection in various animal species. The spike glycoprotein of SARS-CoV-2, which is involved in viral entry, is a highly immunogenic protein. To develop assays targeting this protein, we generated eight monoclonal antibodies (mAbs) against the S1 and seven against the S1/S2 protein (ectodomain) of SARS CoV-2. Based on neutralization capability and reactivity profile observed in ELISA, the mAbs generated against the S1/S2 antigen exhibited a broader spectrum of epitope specificity than those produced against the S1 domain alone. The full-length ectodomain induced antibodies that could neutralize the two most important variants of the virus encountered during the pandemic, namely Delta and Omicron. The availability of these reagents could greatly enhance the development of precise diagnostics for detecting COVID-19 infections in various host species and contribute to the advancement of mAb-based therapeutics.
ABSTRACT
This experimental investigation focuses on the gamma-ray interaction parameters and the buildup factor in lanthanide compounds (CeO2, Ce(SO4)2, Dy2(SO4)3, C3O9Sm2, C3Gd2O9, Pr2O3). These compounds were exposed to weak radioactive gamma sources with energies of 356, 511, 662, 1173, 1275, and 1332 keV by adopting narrow and broad beam geometry experimental arrangements. The incident and transmitted radiation intensities were measured using a NaI (Tl) detector. Experimentally measured values of mass attenuation coefficient and effective atomic number of lanthanide compounds were found to be in precise agreement with theoretical values obtained from NIST XCOM and Direct-Zeff database respectively. Additionally, the experimentally determined buildup factor values were compared with energy absorption buildup factor (EABF) and exposure buildup factor (EBF) values obtained from Phy-X/PSD software, providing insights into the gamma-ray penetration depth in terms of mean free path (MFP). At 356 keV, the EABF analysis showed that most compounds had a penetration depth of around 8 mean free paths. In contrast, the EBF analysis indicated penetration depths exceeding 10 mean free paths for all compounds except Ce (SO4)2. This new approach holds immense potential for transformative advancements in medical diagnostics, therapy, and the development of innovative technologies in nuclear sciences.
ABSTRACT
This experimental approach was designed to understand the gamma interaction parameters for the essential biomolecules, including starch soluble, cholesterol, myristic acid, glucose, oxalic acid, dextrose, salicylic acid, ethyl cellulose and sucrose. The empirical determination of gamma interaction parameters, such as interaction mean-free-path (MFP), buildup factor, and effective atomic number (Zeff) was performed by measuring mass attenuation coefficient (µ/ρ) at energies of 356 keV, 511 keV, 662 keV, 1173 keV, 1275 keV and 1332 keV. This was achieved using weak radioactive sources and a NaI(Tl) scintillation spectrometer with collimated and non-collimated transmission geometry. The experimentally determined values of gamma-ray interaction parameters were obtained non-destructively and precisely agreeing with the expected values from simulations and codes. In addition, the research findings also revealed a novel trend in gamma interaction mean free path as a function of energy and variable buildup factors for the selected biomolecules. These research findings provide valuable insight into the process of gamma radiation interaction. This approach may fulfil the increasing demand of medical, technical and academic research laboratories for a cost-effective and reliable empirical methodology to understand gamma radiation interaction with matter.
Subject(s)
Photons , Gamma RaysABSTRACT
Sheeppox virus (SPPV) is responsible for a significant economic loss to sheep husbandry in enzootic regions of Africa, the Middle East, and Asia including the Indian subcontinent. In this study, we present the complete genome sequence of SPPV vaccine strain SPPV-Srin38/00 from India determined by next-generation sequencing (NGS) using Illumina technology. The attenuated Srinagar vaccine strain of SPPV (SPPV-Srin38/00) was developed by serial passaging the virus initially in lamb testes (LT) cells followed by Vero cell line. The SPPV-Srin38/00 virus has a genome size of 150, 103 bp, which encodes for 147 functional putative genes and consists of a central coding region flanked by two identical 2353 bp inverted terminal repeats (ITRs). Comparative phylogenetic analysis based on complete genome sequences of Capripoxviruses formed three distinct groups each for SPPV, GTPV, and LSDV with clustering of SPPV-Srin38/00 strain with SPPV-A strain. Nine ORFs of SPPV-Srin38/00 namely SPPV-Srin_002/SPPV-Srin_155, SPPV-Srin_004/SPPV-Srin_153, SPPV-Srin_009, SPPV-Srin_013, SPPV-Srin_026, SPPV-Srin_132, and SPPV-Srin_136 were found to be fragmented as compared to LSDV, whereas only one ORF (such as SPPV-Srin_136) was found to be fragmented as compared to GTPV. SPPV genomes, including the SPPV-Srin38/00 strain, shared 99.78-99.98% intraspecies nucleotide identity, indicating that SPPV strains have extremely low genetic diversity. The strain shared 96.80-97.08% and 97.11-97.61% nt identity with GTPV and LSDV strains, respectively. Its ORFs 016, 021, 022, 130 and 138 are the least identical ORFs among three species of the genus Capripoxvirus with 72.5-93% aa identity to GTPV and LSDV strains and may be potentially used for differentiation of CaPV species. This study may contribute to a better understanding of the epidemiology and evolution of capripoxviruses as well as the development of specific detection methods, better expression vectors, and vaccines with improved safety and efficacy.
Subject(s)
Capripoxvirus/genetics , Animals , Capripoxvirus/classification , Chlorocebus aethiops , Genome Size , High-Throughput Nucleotide Sequencing , Open Reading Frames , Sheep , Sheep Diseases/virology , Vero Cells , Whole Genome SequencingABSTRACT
Virus neutralization test (VNT) and liquid phase blocking ELISA (LPBE) are accepted tests for screening and as in vitro alternativ to challenge in FMD vaccine potency testing. To replace VNT by LPBE for the screening of cattle, the optimized tests need to be first evaluated for their diagnostic performances. To replace it with LPBE in the absence of protection data, the interrelationship between VNT and LPBE have to be established to find out LPBE cutoff titer corresponding to the currently used VNT titers. Accordingly, VNT and LPBE were carried out using known negative (n = 306) and positive samples [Serotype O (n = 43), A (n = 14) and Asia1 (n = 11)], for the initial screening. The cutoff of < 1.5 log10 LPBE was comparable with that of < 1.2 log10 VNT titer for screening. LPBE was comparable to VNT in terms of specificity, sensitivity as shown by ROC curve and least varying (coefficient of variation 7.73% in LPBE vs 24.19% in VNT). Based on linear regression model using 471 bovine sera, the predicted LPBE titers corresponding to the currently used log 10 VNT titers of 1.65, 1.5 and 1.5, were 2.24, 1.87 and 2.00 for O, A and Asia1, respectively. These LPBE titers hence can be used as cutoff titers for classifying cattle as protected or not protected until correlation based on in vivo challenge between protection and antibody titer is established.
Subject(s)
Cattle Diseases , Foot-and-Mouth Disease Virus , Foot-and-Mouth Disease , Viral Vaccines , Animals , Antibodies, Viral , Cattle , Cattle Diseases/diagnosis , Cattle Diseases/prevention & control , Enzyme-Linked Immunosorbent Assay/veterinary , Foot-and-Mouth Disease/diagnosis , Foot-and-Mouth Disease/prevention & control , Neutralization Tests/veterinaryABSTRACT
BACKGROUND AND AIM: Foot-and-mouth disease (FMD) is an acute viral infection affecting cloven-hoofed animals causing vesicular erosions in the oral cavity and interdigital space. The present study was undertaken to ascertain the time-dependent changes in clinical, hematological, and biochemical profiles in different breeds of cattle following experimental infection. MATERIALS AND METHODS: The animals were inoculated with 1.0×104 50% bovine tongue infectious dose (BTID50) by intradermolingual route. Clinical signs were observed, and blood/serum samples were collected at different time intervals. RESULTS: The white blood cell count declined sharply on days 7-13 and recovered on day 14 post-FMD infection. Biochemical analysis of serum markers for vital organ profile revealed no marked damage. However, a significant increase in blood urea nitrogen (BUN) value indicated pre-renal azotemia. Transient hyperthyroidism was indicated by the rise in T3 and T4 that can be correlated with a decrease in triglyceride and total cholesterol levels. In the cardiac damage assessment study, a distinct breed difference was observed wherein Malnad Gidda calves showed no cardiac damage. CONCLUSION: Except thyroid profile, BUN, and creatine kinase-myocardial band, all other serum biochemical parameters showed no significant abnormalities, whereas lymphopenia is the only hematological change and it is suggested that effective ameliorative measures should be targeted mainly on the feed/water intake, thyroid gland, and the level of lymphocytes.
ABSTRACT
Foot-and-mouth disease (FMD) is a devastating acute viral disease of livestock with cloven hooves. Among various therapeutic control measures, RNA interference (RNAi) is one of the methods being explored to inhibit FMD virus replication and spread. The RNAi is achieved by short hairpin RNAs or artificial microRNAs (amiRNAs). Utility of amiRNAs as antiviral, targeting conserved regions of the viral genome is gaining importance. However, delivery of miRNA in vivo is still a challenge. In this study, the efficacy of amiRNAs in preventing FMD virus replication in a permissive cell culture system was investigated, by generating stable cell lines expressing amiRNAs targeting three functional regions of the FMD virus (FMDV) genome (IRES, 3B3 and 3D). The results showed that amiRNA targeting 3D polymerase is relatively more efficient. However, expression of multiple microRNAs targeting the three regions did not exhibit additive effect. The data suggest that 3D specific miRNA is a potential valid strategy in developing novel antiviral measures against FMDV infection. Keywords: artificial microRNA; foot-and-mouth disease virus; virus inhibition.
Subject(s)
Foot-and-Mouth Disease Virus , Foot-and-Mouth Disease , MicroRNAs , Virus Replication , Animals , Foot-and-Mouth Disease/virology , Foot-and-Mouth Disease Virus/genetics , MicroRNAs/genetics , RNA Interference , Virus Replication/geneticsABSTRACT
Objective: To study physicochemical properties, antioxidant and anti-inflammatory activities of coumarin-carbonodithioate hybrids. Methods: The substituted 4-bromomethyl coumarins were synthesized in first step by the cyclization. Then the reaction of substituted coumarins (a-e) with potassium O-ethyl/methyl carbonodithioate (1) by using absolute ethanol as solvent,afforded coumarin-carbonodithioate (1a-1j) derivatives under microwave irradiation and the conventional method. The spectroscopic analysis was used for the characterization of coumarin derivatives. The title (1a-1j) compounds were confirmed by spectroscopic methods.Antioxidant property was evaluated by using DPPH free radical-scavenging ability assay method and anti-inflammatory activity was evaluated by protein denaturation procedure using diclofenac sodium as a standard. Drug-likeness. In-silico toxicity was predicted with LD50 value and bioactivity score was also calculated for all the compounds. Results: All coumarin (1a-1j) compounds exhibited promising in-vitro antioxidant and anti-inflammatory properties in comparison to standard drugs. All tested compounds were used for evaluating their physicochemical properties as set by Lipinski rule. It was observed that the synthesized compounds followed rule of five, indicating more 'drug-like' nature. Conclusions: All the screened coumarin-carbonodithioates display promising in vitro antioxidant and antiinflammatory activities. From the physicochemical properties of coumarin derivatives, it is found that none of the compounds violate the Lipinski rule and they fall well in the range of rule of five. It is concluded that the coumarin-carbonodithioate hybrids act with more 'drug-like' nature.
ABSTRACT
Recombinant adenovirus-5 vectored foot-and-mouth disease constructs (Ad5- FMD) were made for three Indian vaccine virus serotypes O, A and Asia 1. Constructs co-expressing foot-and- mouth disease virus (FMDV) capsid and viral 3C protease sequences, were evaluated for their ability to induce a neutralizing antibody response in indigenous cattle (Bos indicus). Purified Ad5-FMD viruses were inoculated in cattle as monovalent (5×109 pfu/animal) or trivalent (5×109 pfu/animal per serotype) vaccines. Animals vaccinated with monovalent Ad5-FMD vaccines were boosted 63days later with the same dose. After primary immunization, virus neutralization tests (VNT) showed seroconversion in 83, 67 and 33% of animals vaccinated with Ad5-FMD O, A and Asia 1, respectively. Booster immunization elicited seroconversion in all of the animals (100%) in the monovalent groups. When used in a trivalent form, the Ad5-FMD vaccine induced neutralizing antibodies in only 33, 50 and 16% of animals against serotypes O, A and Asia 1, respectively on primo-vaccination, and titers were significantly lower than when the same vectors were used in monovalent form. Neutralizing antibody titers differed by serotype for both Ad5-FMD monovalent and trivalent vaccines, with Asia 1 serotype inducing the lowest titers. Antibody response to Ad5 vector in immunized cattle was also assessed by VNT. It appeared that the vector immunity did not impact the recall responses to expressed FMDV antigens on booster immunization. In summary, the study suggested that the recombinant Ad5-FMD vaccine has a potential use in monovalent form, while its application in multivalent form is not currently encouraging.
Subject(s)
Adenoviruses, Human/immunology , Antibodies, Viral/immunology , Capsid Proteins/immunology , Cattle Diseases/prevention & control , Foot-and-Mouth Disease Virus/immunology , Foot-and-Mouth Disease/prevention & control , Viral Vaccines/immunology , Adenoviruses, Human/genetics , Animals , Antibody Formation , Antigens, Viral/immunology , Capsid Proteins/genetics , Cattle , Cattle Diseases/virology , Cell Line , Foot-and-Mouth Disease/virology , Genetic Vectors/genetics , Humans , Immunization, Secondary/veterinary , Vaccination/veterinary , Vaccines, Synthetic/immunologyABSTRACT
BACKGROUND: Brucellosis is an important zoonotic disease. India having a major agrarian population is expected to have a higher prevalence. However, due to lack of laboratory facility or awareness among clinicians, the disease is largely underreported. The aim of this study was to know the prevalence and trend of human brucellosis over a decade, in patients attending a teaching hospital in North Karnataka, and to understand their geographical distribution. MATERIALS AND METHODS: The study was conducted from January 2006 to December 2015 at a tertiary care teaching hospital in North Karnataka. A total of 3610 serum samples were evaluated from suspected cases of brucellosis. All serum samples were initially screened by Rose Bengal plate test, and positive samples were further analysed by Serum agglutination test (SAT) using standard Brucella abortus antigen from Indian Veterinary Research Institute, Izatnagar, Uttar Pradesh, India. A titre above or equal to 1:80 IU/ml was considered as positive. Demographic data such as age, sex and native place of these patients were also analysed. RESULTS: We observed that human brucellosis is present in North Karnataka. The overall seropositivity of brucellosis in suspected cases was 5.1%. The positive titres ranged from 1:80 to 163,840 IU/ml. The majority of the patients were from Gadag, Koppal and Haveri districts of North Karnataka. CONCLUSION: Our study confirms the presence of human brucellosis in the northern part of Karnataka. Further studies to understand the prevalence of animal brucellosis in these areas will help in implementing prevention measures.
Subject(s)
Antibodies, Bacterial/blood , Brucella/immunology , Brucellosis/epidemiology , Adult , Female , Humans , India/epidemiology , Male , Retrospective Studies , Seroepidemiologic Studies , Tertiary Care Centers , Topography, MedicalABSTRACT
Foot-and-mouth disease (FMD) is an important infection affecting the health and productivity of cloven-hoofed livestock. Development of improved vaccines and diagnostic reagents is being explored to facilitate the disease control. There is an emerging interest in virus-like particles (VLPs), as their constituent structural proteins are the major immunogens. The VLPs are similar to natural virus particles but lack viral nucleic acid. The objective of the present study was to express the VLPs of FMD virus (FMDV) serotype Asia-1 (IND 63/72), using baculovirus system and characterize them for antigenic structure. The VLPs expressed in insect cells showed immunoreactivity similar to inactivated cell culture FMDV. Further they possess similar sensitivity to trypsin as the inactivated cell culture FMDV, suggesting that trypsin-sensitive antigenic sites could be similarly arranged. Our findings suggest that the FMD VLPs have similar antigenic conformational feature like the wild type virus, thus supporting their utility in development of non-infectious FMD vaccines and/or diagnostic assays.
Subject(s)
Foot-and-Mouth Disease Virus/immunology , Foot-and-Mouth Disease/virology , Virion/immunology , Animals , Antibodies, Viral/immunology , Foot-and-Mouth Disease/immunology , Foot-and-Mouth Disease Virus/chemistry , Foot-and-Mouth Disease Virus/genetics , Lepidoptera , Recombination, Genetic , Spodoptera , Trypsin/chemistry , Viral Proteins/genetics , Viral Proteins/immunology , Virion/chemistry , Virion/geneticsABSTRACT
Reliable diagnostic tests that are able to distinguish infected from vaccinated animals are a critical component of regional control programs for foot-and-mouth disease (FMD) in the affected countries. Non-structural protein (NSP) serology based on the 3ABC protein has been widely used for this purpose, and several kits are commercially available worldwide. This report presents the development of a 3ABC-antigen-based indirect ELISA, employing a peroxidase-conjugated protein G secondary antibody that can detect antibodies from multiple species. Recombinant 3ABC protein was expressed in insect cells and purified using affinity column chromatography. Using this protein, an indirect ELISA was developed and validated for the detection of NSP antibodies in serum samples collected from animals with different status of FMD. Diagnostic sensitivity and specificity were found to be 95.8 (95 % CI: 92.8-97.8) and 97.45 % (95 % CI: 94.8-99.0), respectively. The in-house ELISA compared well with the commercially available prioCHECK FMDV NS-FMD kit, with a high agreement between the tests, as determined by the kappa coefficient, which was 0.87. The in-house ELISA showed higher sensitivity for detecting vaccinated and subsequently infected animals, when compared to the reference test. Both of the tests were able to detect NSP antibodies as early as 7-8 days after experimental infection.
Subject(s)
Antibodies, Viral/blood , Cattle Diseases/blood , Enzyme-Linked Immunosorbent Assay/methods , Foot-and-Mouth Disease Virus/isolation & purification , Foot-and-Mouth Disease/blood , Viral Nonstructural Proteins/immunology , Animals , Buffaloes , Cattle , Cattle Diseases/diagnosis , Cattle Diseases/virology , Foot-and-Mouth Disease/diagnosis , Foot-and-Mouth Disease/virology , Foot-and-Mouth Disease Virus/classification , Foot-and-Mouth Disease Virus/genetics , Foot-and-Mouth Disease Virus/immunology , Viral Nonstructural Proteins/analysis , Viral Nonstructural Proteins/geneticsABSTRACT
The recombinant baculoviruses were constructed to investigate the necessity of VSV-G pseudotyping for mammalian cell transduction. The viruses were designed to express green fluorescent protein (GFP) gene under the control of cytomegalovirus promoter, with or without pseudotyping with VSV-G. VSV-G was placed under the control of polyhedrin promoter that is recognized by insect cells, allowing the formation of pseudotyped baculovirus. The study findings demonstrate that the pseudotyping of baculovirus significantly enhanced transduction efficiency compared to non-pseudotyped baculovirus, resulting in consequent distinction in the expression of GFP in mammalian cells. The results confirmed that pseudotyping is important for baculovirus mediated gene delivery. Further, when full-length VSV-G pseudotyping was compared with truncated VSV-G containing GED domain (G-stem of ectodomain in conjunction with the TM and CT domains of the glycoprotein), latter was relatively less efficient in transducing mammalian cells. This study demonstrated that pseudotyping with full-length VSV-G had better transduction efficiency in mammalian cells. However, at higher multiplicity of infection, both full-length and truncated VSV-G showed equivalent transduction. This study established the significance of pseudotyping of baculovirus with full-length VSV-G for efficient transduction of mammalian cells, utilizing the highly sensitive GFP marker system. These findings have significant implications in designing of baculovirus vector based antigen delivery for developing new generation vaccines.
ABSTRACT
Vaccination is a well accepted strategy for control of foot-and-mouth disease (FMD) in endemic countries. Currently, chemically inactivated virus antigens are used for preparation of FMD vaccine. To develop a non-infectious and safe recombinant vaccine, we expressed structural polypeptide of FMDV (O/IND/R2/75) using baculovirus expression system. We show that inclusion of mutated viral 3C protease in frame with the polypeptide (P1-2A), enhanced the yield of structural proteins. The structural proteins retained antigenicity and assembled into empty virus-like particles (VLPs). Immunization of guinea pigs with purified fractions of the VLPs resulted in humoral and cell mediated immune response by 4 weeks. The VLPs elicited comparable humoral immune response and relatively higher cell mediated immune response, when compared to conventional vaccine in guinea pigs. Further, up to 70% of the VLP immunized guinea pigs were protected against challenge with homologous guinea pig adapted virus. Our results highlight the application of recombinant FMDV VLPs in FMD vaccination.
Subject(s)
Baculoviridae/immunology , Foot-and-Mouth Disease Virus/immunology , Foot-and-Mouth Disease/prevention & control , Vaccines, Virus-Like Particle/therapeutic use , Viral Vaccines/therapeutic use , Animals , Antibodies, Neutralizing/immunology , Antigens, Viral/immunology , Enzyme-Linked Immunosorbent Assay/veterinary , Female , Foot-and-Mouth Disease/immunology , Guinea Pigs , Immunity, Cellular/immunology , Immunity, Humoral/immunology , Male , Neutralization Tests/veterinary , Vaccines, Synthetic/immunology , Vaccines, Synthetic/therapeutic use , Viral Vaccines/immunologyABSTRACT
In foot-and-mouth disease (FMD) control programme, liquid-phase blocking ELISA (LPBE) is widely used to assay vaccine-induced seroconversion. Currently, the assay utilizes inactivated FMD virus antigen for the detection of antibodies in serum samples. To develop a non-infectious substitute for the antigen in LPBE, we expressed the structural polypeptide of FMDV (serotype A) using a baculovirus expression system, and show that inclusion of viral 3C with reduced protease activity resulted in a higher yield of structural proteins. Structural proteins expressed in insect cells assembled into empty virus-like particles (VLPs) and showed antigenicity comparable to chemically inactivated FMDV. Screening of serum samples from FMD-vaccinated cattle showed that the test performance of VLP-LPBE had a correlation of 0.89 with conventional inactivated virus antigen LPBE. The VLP-LPBE developed here demonstrates the diagnostic application of recombinant FMDV VLPs in monitoring seroconversion following FMD vaccination.
Subject(s)
Antibodies, Viral/blood , Antigens, Viral , Capsid Proteins , Foot-and-Mouth Disease Virus/immunology , Foot-and-Mouth Disease/immunology , Veterinary Medicine/methods , Viral Vaccines/immunology , Animals , Antigens, Viral/immunology , Capsid Proteins/immunology , Cattle , Cattle Diseases/immunology , Cattle Diseases/prevention & control , Enzyme-Linked Immunosorbent Assay/methods , Foot-and-Mouth Disease/prevention & control , Recombinant Proteins/immunology , Serologic Tests/methodsABSTRACT
Sequence variability within the capsid coding region of the foot-and-mouth disease virus type A vaccine strain during serial in vitro passage was investigated. Specifically, two methods of virus propagation were utilized, a monolayer and suspension culture of BHK-21 cells. At three positions (VP2(131) E-K in both monolayer and suspension passages, VP3(85) H-R in late monolayer passages and VP3(139) K-E in only suspension passages), all mapped to surface exposed loops, amino acid substitutions were apparently fixed without reversion till the end of the passage regime. Interestingly, VP2(131, 121) and VP3(85) which form part of the heparan sulphate binding pocket, showed a tendency to acquire positively charged amino acids in either monolayer or suspension environment probably to better interact with the negatively charged cell surface glycosaminoglycans. At three identified antigenically critical positions (VP2(79), VP3(139) and VP1(154)), amino acids substitutions even in the absence of immune pressure were noticed. Hence both random drift and adaptive mutations attributable to the strong selective pressure exerted by the proposed cell surface alternate receptors could play a role in modifying the capsid sequence of cell culture propagated FMDV vaccine virus, which in turn may alter the desired potency of the vaccine formulations.
Subject(s)
Capsid , Foot-and-Mouth Disease Virus/immunology , Serial Passage , Viral Vaccines/genetics , Animals , Base Sequence , Cell Adhesion , Cell Line , Cricetinae , DNA Primers , Guinea Pigs , Models, Molecular , Viral Vaccines/immunologyABSTRACT
Non-structural proteins (NSPs) based diagnostics are useful for large-scale sero-surveillance of foot-and-mouth disease (FMD) and to monitor viral activity as a follow up to the vaccination campaign in FMD endemic countries like India which aim at disease control through vaccination. These diagnostics are also handy in the serology of import/export of cloven-footed animals. In the present study, non-structural protein RNA polymerase (3D gene) of FMD virus (FMDV) was expressed using baculovirus expression system. Protein expression was analyzed by SDS-PAGE and confirmed by its immuno-reactivity with serum from a FMDV infected bovine, in the western blot. Recombinant 3D protein was purified and evaluated in the indirect ELISA with 1072 cattle serum samples. Diagnostic sensitivity and specificity of the assay were found to be 92 and 100 %, respectively, when tested with cattle sera of known FMD status. The 3D based ELISA developed here is useful for screening the animals as an adjunct to other NSP based diagnostics available for routine serosurveillance of FMD.
ABSTRACT
Among the members of the genus Orthopoxvirus (OPXV), vaccinia virus (VACV), the type species of the genus is a double-stranded DNA virus, belongs to the subfamily Chordopoxvirinae of the family Poxviridae. The causative agents of smallpox, VACV and Variola virus are mutually immunogenic and the type species of Orthopoxvirus, cause only mild complications in humans. Therefore, the VACV was used as a smallpox vaccine world over under mass immunization program promoted by World Health Organization, which lead to the variola eradication globally in 1979. Since then, no vaccination of human population has been carried out; however, vaccination has been continued for at-risk laboratory workers, military personnel and others working with recombinant VACV or other non-variola orthopoxviruses (OPXVs). There has now been a surge in the development of safer smallpox vaccines and understanding of the biology of VACV necessitating re-use of this vaccine in most vulnerable population, because of rise in bioterrorist threats globally. Also, globally there has been the emergence and re-emergence of vaccinia-like viruses (VLVs) in Brazil, buffalopox viruses in Egypt, Indonesia, India and its neighbouring countries like Nepal, Pakistan. Bioterrorism as well as emergence and re-emergence of the VLVs constitute a concern as 50 % of the population globally (40 % in USA) <30 years are unvaccinated and most vulnerable for smallpox reemergence. Thus, the search for new generation safer smallpox vaccine entails review of biology of VLVs in the smallpox-free world. In this review, we present occurrence of VLVs in the world with exhaustive discussion particularly on the emergence and re-emergence of these viruses in India and Brazil where VLVs are sufficiently studied.
ABSTRACT
In the present study, two sheeppox vaccines made from strains [sheeppox virus-Srinagar (SPPV-Srin) and Ranipet (SPPV-R)] indigenous to India and adapted to Vero cells were compared in terms of their safety, potency, efficacy and antigenic value with the commercial in-use Roumanian Fanar (SPPV-RF) vaccine, a foreign strain adapted in primary lamb testes cells. The safety test indicated that the SPPV (Sri and RF) vaccines were safe while SPPV-R was not completely attenuated and caused excessive adverse reactions at the passage level tested. The immunized animals showed DTH reaction and resisted virulent SPPV challenge, while control animals developed disease. Specific virus could be detected in the controls and animals immunized with lower dilutions of vaccines after challenge but not in any of the sheep immunized with 1 and 100 doses of each vaccine. All vaccines were found potent and the PD(50) was highest for SPPV (Srin and R) followed by RF. The immunized animals were seroconverted following vaccination with sustained antibody responses after challenge. In conclusion, indigenous SPPV-Srin vaccine was found to be as efficacious as SPPV-R and SPPV-RF vaccines. Thus, there is potential benefit in replacing the currently used commercial vaccine SPPV-RF with indigenous SPPV-Srin vaccine for use in India.
Subject(s)
Capripoxvirus/immunology , Poxviridae Infections/immunology , Sheep Diseases/immunology , Viral Vaccines/immunology , Animals , Antibodies, Viral/blood , Antibodies, Viral/immunology , Capripoxvirus/classification , Chlorocebus aethiops , Dose-Response Relationship, Drug , Poxviridae Infections/prevention & control , Sheep , Sheep Diseases/prevention & control , Sheep Diseases/virology , Species Specificity , Time Factors , Treatment Outcome , Vaccination/methods , Vaccines, Attenuated/administration & dosage , Vaccines, Attenuated/immunology , Vero Cells , Viral Vaccines/administration & dosageABSTRACT
Sheeppox and goatpox, two endemic capripox infections in India, pose a significant economic threat to small ruminant productivity in the subcontinent. Vaccination of all susceptible sheep and goats is the feasible and sustainable means of control. Availability of effective live attenuated vaccines that are inherently thermostable and development of improved diagnostics provide the opportunities to initiate effective control measures for capripox. All animals older than 4 months can be vaccinated with the current homologous vaccines using a single vaccination by intradermal or subcutaneous routes. The success of the control program needs to be monitored by active surveillance particularly for the presence of virus, as sero-monitoring does not enable the differentiation of infection and vaccination. And also the sero-conversion following capripox vaccination is not detectable enough by the available tools. Sustained control efforts call for socio-economic and political stability, adequate infrastructure and logistic support to store and transport vaccines for reaching out vaccines to the remote end users. Availability of veterinary services, improved extension services for increased awareness among farmers, contribute significantly to the control campaigns. Poor vaccination coverage and in-adequate infrastructure in major parts of the country are some of the major elements that come in the way of effective implementation of building herd immunity through immunization.