Three strains of the FMD virus (A, O, and SAT 2) were recognised as causes of the FMD circulating in Egypt. The aims of this study were to trace the FMDV isolates from outbreaks in Egypt to understand their epidemiology and evolution and to understand the situation of the vaccine strains compared with the circulating serotypes. A meta-analysis was carried out by using the data available for FMD outbreaks in Egypt from GenBank and the World Reference Laboratory for Foot-and-Mouth Disease (WRLFMD); a comparison was done with both data sets for the three serotypes. MEGA-X was used for the evolution analysis, through constructions of phylogenetic trees for all sequences recorded in GenBank for each serotype in different Egyptian outbreaks in different years and also within the same year. Additionally, nucleotide substitution rate, molecular clock, and mean evolutionary rates were estimated for the three serotypes to understand and compare their evolution. Absence of some records of certain serotype outbreaks from the WRLFMD database was noted as were subsequent missing appropriate vaccine programmes. Genetic variation was recorded among the virus isolates within the same years and also the vaccine strain was associated with up to 26 amino acid substitutions. The evolution rate of the SAT2 strain was the highest of the circulating strains. SAT2 had high amino acid substitution per year at an important immunogenic site (130–170), serotype A had less, and serotype O the least. The need for different strategies for vaccine serotype selection is indicated.

Introduction: Canine transmissible venereal tumour (CTVT) is a sexually transmitted tumour affecting dogs worldwide, imposing a financial burden on dog owners. A stable culture cell line in continuous passages for >18 months has only been achieved once. The present study investigated a stable CTVT cell line isolated from a bitch and its potential as a vaccine. Material and Methods: A biopsy from a 2-year-old mongrel bitch with CTVT was obtained for histopathological confirmation and isolation of tumour cells. The isolated cells were cultured to passage 55 and characterised by flow cytometry, with karyotyping by GTG-banding and by PCR detection of myc S-2 and LINE AS1. The isolated CTVT cell line was also used as a preventive vaccine in a canine model. Results: Histopathological analysis of the isolated tumour cells revealed typical CTVT characteristics. Constant proliferation and stable morphological characteristics were observed during culture. Phenotypic analysis determined the expression of HLA-DR⁺, CD5.1⁺, CD14⁺, CD45⁺, CD83⁺, CD163⁺, and Ly-6G-Ly-6C⁺. GTG-banding revealed a mean of 57 chromosomes in the karyotype with several complex chromosomal rearrangements. LINE-c-myc insertion in the isolated CTVT cell line at 550 bp was not detected. However, a 340-bp band was amplified. Isolated CTVT cell line inoculation at a concentration of 1×10⁸ did not induce tumour growth in bitches, nor did a challenge with primary CTVT cells. Conclusion: The present study successfully identified and isolated a stable CTVT cell line that may be useful in CTVT prevention.

Since 2007, African swine fever (ASF) has posed a serious threat to the European swine industry. In Poland, the numbers of reported outbreaks in pigs and affected areas grow every year. In 2018, the disease was noted in Western Europe, in Belgium specifically, where several hundred infected wild boars have been detected so far. In 2018, the virus unexpectedly emerged in pig holdings in eastern China, northern Mongolia, Vietnam, and Cambodia, causing worldwide concern about its further spread. Since there is still no vaccine available, the only approach to control the disease is biosecurity. Identification of potential sources of the virus is extremely important in light of its phenomenal survivability. The review summarises the current knowledge about ASFV survivability and resistance to environmental conditions, and discusses the role of indirect contact in spreading the disease.

Mycoplasma bovis is known as a causative agent of many disorders in cattle. In Europe, there is still a lack of commercial vaccines against M. bovis infection. Acute phase response (APR) is a non-specific host reaction to infection, most seen in changes in production of acute phase proteins. The aim of this study was to analyse APR in calves administered with an experimental M. bovis vaccine. Twelve healthy female calves were divided into two equal groups: experimental and control. The experimental vaccine containing the field M. bovis strain and two adjuvants such as saponin and lysozyme dimer was subcutaneously administered to the experimental group. Phosphate buffered saline was taken as the placebo and given to the control group by the same route as the vaccine. Blood samples were collected prior to the study (day 0), then daily up to day 7, and then each seven days until day 84 post vaccination. The concentrations of serum amyloid A (SAA), haptoglobin (Hp), interferon-γ (IFN-γ), and inteleukin-4 (IL-4) were determined using commercial ELISA kits. Following the vaccination, a significant increase in SAA, Hp, and IFN-γ concentrations was observed when compared to the unvaccinated calves, whereas the IL-4 concentration was not detectable. The experimental saponin-based M. bovis vaccine containing lysozyme dimer adjuvant visibly stimulated the APR in the calves, and some specific cytokines (Th1-dependent) directly involved in this response.

African swine fever (ASF) is currently one of the most severe viral infections of domestic pigs, wild boars, and other hosts belonging to Suidae family. ASF is also considered as the most complex and devastating infectious and haemorrhagic disease of swine due to its severe socio-economic impact and transboundary character. ASF it is a notifiable disease and due to the lack of specific treatment and vaccine, the disease can be only limited by the administrative measures comprising wild boar hunting and stamping out of affected pigs. ASF occurred for the first time in Kenya in 1921 while in Europe (Portugal) the virus was detected at the end of the 1950s. In spite of successful eradication of this threat in a number of affected regions, the virus remains endemic in both feral and domestic pigs in Africa and Sardinia. The ‘new era’ of ASF started in 2007 after its re-introduction to Georgia. Following its intensive expansion, the virus spread to other Caucasian countries, including the territory of the Russian Federation. In 2014 the virus reached Ukraine, Belarus, and, consequently, European Union countries: Lithuania, Latvia, Estonia, and Poland. The occurrence of ASF in wild boars and pigs had a severe impact on both epidemiology and economy because of the national and international transport and trade consequences. Up to date, starting from the February 2014, eighty ASF cases in wild boar and three outbreaks in domestic pigs have been diagnosed. Taking into account the diverse rate of spread in Poland, this review aims to present and discuss the current state of knowledge on ASF including its epidemiology, pathology, transmission, and perspectives of control.

African swine fever virus (ASFV) causes one of the most dangerous diseases of pigs and wild boar – African swine fever (ASF). Since its second introduction into Europe (in 2007), the disease has been spreading consistently, and now ASF-free European countries are at risk. Complex interactions between the host’s immune system and the virus have long prevented the development of a safe vaccine against ASF. This study analysed the possibility of neutralisation of the ASFV in vitro by sera collected from ASF-survivor animals. Two pig and three wild boar serum samples were collected from previously selected potential ASF survivors. All sera presented high antibody titres (>5 log₁₀/mL). Primary alveolar macrophages were cultured in growth medium containing 10% and 20% concentrations of selected sera and infected with a haemadsorbing ASFV strain (Pol18_28298_O111, genotype II). The progress of infection was investigated under a light microscope by observing the cytopathic effect (CPE) and the haemadsorption phenomenon. Growth kinetics were investigated using a real-time PCR assay. Haemadsorption inhibition was detected in the presence of almost all selected sera; however, the inhibition of virus replication in vitro was excluded. In all samples, a CPE and decreasing quantification cycle values of the viral DNA were found. Anti-ASFV antibodies alone are not able to inhibit virus replication. Interactions between the humoral and cellular immune response which effectively combat the disease are implicated in an ASF-survivor’s organism.

Granulocyte-macrophage colony stimulating factor (GM-CSF) and interleukin-4 (IL-4) are cytokines widely used in ex vivo monocyte differentiation experiments, vaccine formulations and disease treatment. The aim of this study was to produce recombinant bovine GM-CSF and IL-4 in an episomal expression system that conserves the postransductional modification of the native proteins and to use the products to differentiate bovine monocytes into dendritic cells. The recombinant proteins rGM-CSF and rIL-4 were expressed in PEAKrapid CRL-2828 human kidney cells, ATCC CRL-2828. The functional activity of the recombinant cytokines was monitored by registering morphological changes in bovine monocytes and assessing the expression of CD14 upon incubation with them. Both recombinant proteins were detected in the cell culture supernatant of transfected cells. Culture supernatants of transfected cells induced in bovine monocytes morphological changes that resemble macrophages or dendritic cells. In addition, bovine cells treated with rGM-CSF and rIL-4 showed reduced expression of the macrophage surface marker CD14 compared with untreated cells. This effect indicates the expected differentiation. The expression of the cytokines was stable after many successive cell passages and a freeze/thaw cycle. The semi-stable mammalian episomal expression system used in this study allowed us to easily produce functional bovine rGM-CSF and rIL-4 without the need for protein purification steps.

Swine DNA viruses have developed unique mechanisms for evasion of the host immune system, infection and DNA replication, and finally, construction and release of new viral particles. This article reviews four classes of DNA viruses affecting swine: porcine circoviruses, African swine fever virus, porcine parvoviruses, and pseudorabies virus. Porcine circoviruses belonging to the Circoviridae family are small single-stranded DNA viruses causing different diseases in swine including poly-weaning multisystemic wasting syndrome, porcine dermatitis and nephropathy syndrome, and porcine respiratory disease complex. African swine fever virus, the only member of the Asfivirus genus in the Asfarviridae family, is a large double-stranded DNA virus and for its propensity to cause high mortality, it is currently considered the most dangerous virus in the pig industry. Porcine parvoviruses are small single-stranded DNA viruses belonging to the Parvoviridae family that cause reproductive failure in pregnant gilts. Pseudorabies virus, or suid herpesvirus 1, is a large double-stranded DNA virus belonging to the Herpesviridae family and Alphaherpesvirinae subfamily. Recent findings including general as well as genetic classification, virus structure, clinical syndromes and the host immune system responses and vaccine protection are described for all four swine DNA virus classes.

Canine parvovirus (CPV) disease is one of the most threatening to domestic and wild dogs. A total of 132 clinical samples were isolated from domestic dogs with diarrhoea from Henan, Hubei, Jiangsu, and Anhui provinces from 2016 to 2017, and 56 were positive for CPV-2 by PCR. A phylogenetic tree was constructed for the isolate sequences incorporating 53 non-Chinese reference strains. VP2 sequences showed the strains mainly to be new CPV-2a/2b and CPV-2c genotypes. The Ala5Gly, Phe267Tyr, Ser297Ala, Tyr324Ile, Gln370Arg, Asn426Asp or Asn426Glu, and Thr440Ala sites in the VP2 protein antigenic region were found to have high mutation rates. The VP2 tertiary structural model shows that the change at these mutation points is a factor for the changes in the protein structure. Significant differences between the Central Chinese strains and others were found, indicating that evolution is geographically related and extended in major regions. The homology between the identified strains confirmed their relationship. Phylogenetic analysis indicated that the common genotypes in the same clusters differ slightly in homology and evolutionary history. This epidemiological study enriches the available data and serves as an important reference for studies on the evolution of CPV and selection of vaccines in China.

Avian reticuloendotheliosis (RE) represents an important immunosuppressive disease of poultry. The occurrence of RE in both chickens and turkeys has an immunosuppressive effect and may lead to vaccination failures. Avian reticuloendotheliosis virus (REV) is widely distributed in different kinds of birds, causing subclinical infections. Another important issue adhering to this disease is contamination of vaccines against fowl pox (FP) and Marek’s disease (MD) with REV. The capability of REV to integrate into the genome of other larger DNA viruses complicates its diagnosis and prevention. There are no efficient vaccines against RE nor treatment, which also complicates how to limit its impact on poultry farming. This paper reviews the current state of knowledge of this important immunosuppressive agent of poultry emphasising the importance of this problem in terms of diagnosis of RE.