High-Pressure Processing of Different Tissue Homogenates from Pigs Challenged with the African Swine Fever Virus.

African swine fever (ASF) is a disease that is a growing threat to the global swine industry. Regulations and restrictions are placed on swine movement to limit the spread of the virus. However, these are costly and time-consuming. Therefore, this study aimed to determine if high-pressure processing (HPP) sanitization techniques would be effective against the ASF virus. Here, it was hypothesized that HPP could inactivate or reduce ASF virus infectivity in tissue homogenates. To test this hypothesis, 30 aliquots of each homogenate (spleen, kidney, loin) were challenge-infected with the Turin/83 strain of ASF, at a 10 7.20 median hemadsorption dose (HAD)50/mL. Subsequently, eight aliquots of each homogenate were treated with 600 millipascal (600 MPa) HPP for 3, 5, and 7 min. Six untreated aliquots were used as the controls. Virological results showed a reduction in the viral titer of more than 7-log. These results support the validity of the study hypothesis since HPP treatment was effective in inactivating ASFV in artificially prepared samples. Overall, this study suggests the need for further investigation of other ASFV-contaminated meat products.

Assessment of BoAHV-1 Seronegative Latent Carrier by the Administration of Two Infectious Bovine Rhinotracheitis Live Marker Vaccines in Calves.

Seronegative latent carriers (SNLCs) are animals that carry the virus without detectable antibodies and pose a risk for disease transmission and diagnostic challenges, suggesting the importance of consideration of marker vaccines in managing them. Therefore, in this study, we evaluated two modified live infectious bovine rhinotracheitis (IBR) marker vaccines (single and double deletions) for their ability to generate SNLC calves. These vaccines were administered to four groups (n = 3 in each group) of three-month-old calves in the presence or absence of passive immunity. Three hundred days after the first vaccination and after confirming the IBR seronegativity of all animals, dexamethasone was administered intravenously for five consecutive days. Only animals immunized with the modified live IBR marker vaccine (single deletion) in the absence of passive immunity exhibited a more enduring immune response than those vaccinated in the presence of passive immunity. Moreover, the administration of a modified live IBR marker vaccine (double deletion) to calves with passive immunity generated SNLC. These findings underscore the potential of live IBR marker vaccine (double-deletions) to aid serological diagnostic tools and develop vaccination protocols in achieving the desired immune response, particularly in the context of latent carrier status, offering valuable insights into optimizing vaccination strategies for effective IBR control.

The Production of Recombinant African Swine Fever Virus Lv17/WB/Rie1 Strains and Their In Vitro and In Vivo Characterizations.

Lv17/WB/Rie1-Δ24 was produced via illegitimate recombination mediated by low-dilution serial passage in the Cos7 cell line and isolated on PAM cell culture. The virus contains a huge ~26.4 Kb deletion in the left end of its genome. Lv17/WB/Rie1-ΔCD-ΔGL was generated via homologous recombination, crossing two ASFV strains (Lv17/WB/Rie1-ΔCD and Lv17/WB/Rie1-ΔGL containing eGFP and mCherry markers) during PAM co-infection. The presence of unique parental markers in the Lv17/WB/Rie1-ΔCD-ΔGL genome indicates at least two recombination events during the crossing, suggesting that homologous recombination is a relatively frequent event in the ASFV genome during replication in PAM. Pigs infected with Lv17/WB/Rie1-Δ24 and Lv17/WB/Rie1/ΔCD-ΔGL strains have shown mild clinical signs despite that ASFV could not be detected in their sera until a challenge infection with the Armenia/07 ASFV strain. The two viruses were not able to induce protective immunity in pigs against a virulent Armenia/07 challenge.

Evaluation of Haematological and Immunological Parameters of the ASFV Lv17/WB/Rie1 Strain and Its Derived Mutant Lv17/WB/Rie1/d110-11L against ASFV Challenge Infection in Domestic Pigs.

African swine fever virus (ASFV) is the etiological agent of a haemorrhagic disease that threatens the global pig industry. There is an urgency to develop a safe and efficient vaccine, but the knowledge of the immune-pathogenetic mechanisms behind ASFV infection is still very limited. In this paper, we evaluated the haematological and immunological parameters of domestic pigs vaccinated with the ASFV Lv17/WB/Rie1 strain or its derived mutant Lv17/WB/Rie1/d110-11L and then challenged with virulent Armenia/07 ASFV. Circulating levels of C-reactive protein (CRP), 13 key cytokines and 11 haematological parameters were evaluated throughout the study. Lv17/WB/Rie1 triggered an inflammatory response, with increased levels of CRP and pro-inflammatory cytokines, and induced lymphopenia, thrombocytopenia and a decline in red blood cell (RBC) parameters, although this was transitory. Lv17/WB/Rie1/d110-11L triggered only transitory thrombocytopenia and a mild inflammatory reaction, with no increase in serum levels of pro-inflammatory cytokines, but it raised IL-1Ra levels. Both strains counteracted several adverse reactions elicited by virulent challenge, like thrombocytopenia, a decline in RBC parameters, and inflammation. Within this paper, we provided a deep portrayal of the impact of diverse ASFV strains on the domestic pig's immune system. A better understanding of these immune-pathological mechanisms would help to design suitable vaccines against this disease.

Complete Genome of African Swine Fever Virus Genotype II in Central Italy.

We report here the whole-genome sequence of the African swine fever virus (ASFV) genotype II, strain 20355/RM/2022_Italy, identified in a wild boar in the city of Rome (Lazio region, Italy) in April 2022.

Molecular Characterization of the First African Swine Fever Virus Genotype II Strains Identified from Mainland Italy, 2022.

African swine fever (ASF) is responsible for important socio-economic effects in the global pig industry, especially for countries with large-scale piggery sectors. In January 2022, the African swine fever virus (ASFV) genotype II was identified in a wild boar population in mainland Italy (Piedmont region). This study describes the molecular characterization, by Sanger and next-generation sequencing (NGS), of the first index case 632/AL/2022 and of another isolate (2802/AL/2022) reported in the same month, in close proximity to the first, following multiple ASF outbreaks. Phylogenetic analysis based on the B646L gene and NGS clustered the isolates 632/AL/2022 and 2802/AL/2022 within the wide and most homogeneous p72 genotype II that includes viruses from European and Asian countries. The consensus sequence obtained from the ASFV 2802/AL/2022 isolate was 190,598 nucleotides in length and had a mean GC content of 38.38%. At the whole-genome level, ASF isolate 2802/AL/2022 showed a close genetic correlation with the other representative ASFV genotype II strains isolated between April 2007 and January 2022 from wild and domestic pigs in Eastern/Central European (EU) and Asian countries. CVR subtyping clustered the two Italian ASFV strains within the major CVR variant circulating since the first virus introduction in Georgia in 2007. Intergenic region I73R-I329L subtyping placed the Italian ASFV isolates within the variant identical to the strains frequently identified among wild boars and domestic pigs. Presently, given the high sequence similarity, it is impossible to trace the precise geographic origin of the virus at a country level. Moreover, the full-length sequences available in the NCBI are not completely representative of all affected territories.

Evaluation of Safety and Efficacy of an Inactivated Marker Vaccine against Bovine alphaherpesvirus 1 (BoHV-1) in Water Buffalo (Bubalus bubalis).

Recent studies have explored the seropositivity of Bovine alphaherpesvirus 1 (BoHV-1) in water buffaloes, suggesting the urgency for developing strategies to eradicate the virus involving both cattle and water buffaloes. However, in Europe, the glycoprotein E (gE) deleted marker vaccines against BoHV-1 are commercially available only for the cattle industry. This study, for the first time, evaluated the safety and efficacy of a commercial inactivated gE-deleted marker vaccine in water buffalo. Five animals devoid of BoHV-1-neutralizing antibodies were vaccinated via intramuscular route. Five additional animals served as an unvaccinated control group. Sixty days after the first immunization, all animals were experimentally infected with a virulent BoHV-1via intranasal route. A detectable BoHV-1-humoral immune response was observed in the vaccinated group on post-vaccination day 30, whereas the antibodies appeared on post-challenge day 10 in the control group. Moreover, the vaccinated animals neither show viral shedding nor clinical signs compared to the control upon challenge. However, post-challenge, the BoHV-1-specific humoral and cell-mediated immune responses were significantly more increased in vaccinated animals than the control animals. Overall, the present study provides evidence of both the safety and efficacy of an inactivated gE-deleted marker vaccine against BoHV-1 in water buffaloes.

Bovine malignant catarrhal fever: case reporting in Central Italy.

A case of malignant catarrhal fever (MCF) occurred in a 4­month­old calf housed in a semi­intensive herd in central Italy is described. The herd was in strict cohabitation with a group of domestic sheep. The calf displayed clinical signs that resembled the acute form of MCF and, after a few days of antibiotic and anti inflammatory therapy, died in September 2016. The diagnosis was confirmed in vivo in blood by detection of ovine herpesvirus type 2 DNA through real­time PCR. At necropsy, the gross post­mortem findings were typical of MCF and the histological and molecular assays confirmed the presence of the virus. The sheep flock was suspected to be the source of the infection. In Italy, as well as in Europe, there is little data regarding the epidemiology and the recurrence of the disease in herds of cattle, due to the lack of an active surveillance plan and to a major consideration of MCF between differential diagnosis.

Intracellular quantitative detection of human thymidylate synthase engagement with an unconventional inhibitor using tetracysteine-diarsenical-probe technology.

Demonstrating a candidate drug's interaction with its target protein in live cells is of pivotal relevance to the successful outcome of the drug discovery process. Although thymidylate synthase (hTS) is an important anticancer target protein, the efficacy of the few anti-hTS drugs currently used in clinical practice is limited by the development of resistance. Hence, there is an intense search for new, unconventional anti-hTS drugs; there are approximately 1600 ongoing clinical trials involving hTS-targeting drugs, both alone and in combination protocols. We recently discovered new, unconventional peptidic inhibitors of hTS that are active against cancer cells and do not result in the overexpression of hTS, which is a known molecular source of resistance. Here, we propose an adaptation of the recently proposed tetracysteine-arsenic-binding-motif technology to detect and quantitatively characterize the engagement of hTS with one such peptidic inhibitor in cell lysates. This new model can be developed into a test for high-throughput screening studies of intracellular target-protein/small-molecule binding.

Enhanced anti-hyperproliferative activity of human thymidylate synthase inhibitor peptide by solid lipid nanoparticle delivery.

Recently, octapeptide LSCQLYQR (LRp), reducing growth of cis-platinum (cDDP) resistant ovarian carcinoma cells by inhibiting the monomer-monomer interface of the human enzyme thymidylate synthase, has been identified. As the peptide is not able to cross the cell membrane it requires an appropriate delivery system. In this work the application of SLNs, biocompatible and efficient tools for the intracellular drug transport, applied especially for lipophilic drugs, was exploited for the delivery of the hydrophilic peptide LRp. SLNs formulated in the absence/presence of small amount of squalene showed dimensions below 150 nm, negative zeta potential and good stability to the freeze-drying process. Even though the particles formulated with squalene exhibited a less ordered crystal lattice and a lower surface hydrophobicity, a rapid drug release from these nanocarriers occurred as a result of the relevant expulsion of the drug from the lipid core during lipid crystallization. On the contrary, SLNs formulated in the absence of squalene were able to incorporate more stably the peptide showing considerable cytotoxic effect on cDDP resistant C13* ovarian carcinoma cell line at concentration 50 times lower than that used previously with a marketed delivery system. From the cell cycle analysis by the propidium iodide test in SLNs-peptide treated cancer cells an increase of apoptosis percentage was observed, indicating that SLNs were able to carry efficiently the peptide until its enzymatic target.

Internalization and stability of a thymidylate synthase Peptide inhibitor in ovarian cancer cells.

Information on the cellular internalization and stability of the ovarian cancer cell growth inhibitor peptide, LSCQLYQR (LR), is vital for lead optimization. Ad-hoc-synthesized LR/fluorescent-probe conjugates were used to monitor the internalization of the peptide. Mass spectrometry was used to identify adducts resulting from the thiol reactivity of the cysteine residue in LR. A mechanistic model is proposed to explain the observed change in intracellular peptide amount over time. Structural modifications can be foreseen to improve the peptide stability.

Mass spectrometric/bioinformatic identification of a protein subset that characterizes the cellular activity of anticancer peptides.

The preclinical study of the mechanism of action of anticancer small molecules is challenging due to the complexity of cancer biology and the fragmentary nature of available data. With the aim of identifying a protein subset characterizing the cellular activity of anticancer peptides, we used differential mass spectrometry to identify proteomic changes induced by two peptides, LR and [d-Gln(4)]LR, that inhibit cell growth and compared them with the changes induced by a known drug, pemetrexed, targeting the same enzyme, thymidylate synthase. The quantification of the proteome of an ovarian cancer cell model treated with LR yielded a differentially expressed protein data set with respect to untreated cells. This core set was expanded by bioinformatic data interpretation, the biologically relevant proteins were selected, and their differential expression was validated on three cis-platinum sensitive and resistant ovarian cancer cell lines. Via clustering of the protein network features, a broader view of the peptides' cellular activity was obtained. Differences from the mechanism of action of pemetrexed were inferred from different modulation of the selected proteins. The protein subset identification represents a method of general applicability to characterize the cellular activity of preclinical compounds and a tool for monitoring the cellular activity of novel drug candidates.

A novel and facile synthesis of tetra branched derivatives of nociceptin/orphanin FQ.

Branched peptides have been found to be useful in several research fields however their synthesis and purification is complicated. Here we present a novel and facile synthesis of tetra branched derivatives of nociceptin/orphanin FQ (N/OFQ). Three N/OFQ tetra branched derivatives were prepared using novel cores (PWT1, PWT2 and PWT3) containing a maleimido moiety. [Cys(18)]N/OFQ-NH2 was linked to the cores via thiol-Michael reaction characterized by high yield and purity of the desired final product. In the electrically stimulated mouse vas deferens PWT-N/OFQ derivatives mimicked the inhibitory action of the natural sequence showing similar maximal effects and 3 fold higher potencies. The NOP selective antagonist SB-612111 antagonized the effects of N/OFQ and PWT derivatives with similar pKB values (8.02-8.48). In vivo after supraspinal administration PWT2-N/OFQ stimulated food intake in mice mimicking the action of N/OFQ. Compared to the natural peptide PWT2-N/OFQ was 40 fold more potent and elicited larger effects. These findings suggest that the PWT chemical strategy can be successfully applied to biologically active peptides to generate, with unprecedented high purity and yield, tetra branched derivatives displaying an in vitro pharmacological profile similar to that of the natural sequence associated, in vivo, to increased potency and effectiveness.

N-carbamidoyl-4-((3-ethyl-2,4,4-trimethylcyclohexyl)methyl)benzamide enhances staurosporine cytotoxic effects likely inhibiting the protective action of Magmas toward cell apoptosis.

We recently demonstrated that Magmas overexpression protects GH-secreting rat pitutitary adenoma cell lines from apoptosis by inhibiting cytochrome c release from mitochondria after treatment with staurosporine, strongly suggesting a role of Magmas in preventing apoptosis. The aim of this study was to produce a drug that, by inhibiting Tim16, may sensitize chemoresistant tumor cell to proapoptotic stimuli. We synthesized six compounds and challenged their sensitizing effects toward the proapoptotic effects of staurosporine in the TT cell line, derived from a human medullary thyroid carcinoma. We found that compound 5, devoid of the planarity in the aliphatic part of the lead 1, is not cytotoxic but enhances the proapoptotic effects of staurosporine by reducing MMP activation. Compound 5 may be useful for cancer treatment in association with chemotherapeutic drugs, possibly allowing a reduction of the chemotherapeutic agent effective dose.

Optimization of peptides that target human thymidylate synthase to inhibit ovarian cancer cell growth.

Thymidylate synthase (TS) is a target for pemetrexed and the prodrug 5-fluorouracil (5-FU) that inhibit the protein by binding at its active site. Prolonged administration of these drugs causes TS overexpression, leading to drug resistance. The peptide lead, LR (LSCQLYQR), allosterically stabilizes the inactive form of the protein and inhibits ovarian cancer (OC) cell growth with stable TS and decreased dihydrofolate reductase (DHFR) expression. To improve TS inhibition and the anticancer effect, we have developed 35 peptides by modifying the lead. The d-glutamine-modified peptide displayed the best inhibition of cisplatin-sensitive and -resistant OC cell growth, was more active than LR and 5-FU, and showed a TS/DHFR expression pattern similar to LR. Circular dichroism spectroscopy and molecular dynamics studies provided a molecular-level rationale for the differences in structural preferences and the enzyme inhibitory activities. By combining target inhibition studies and the modulation pattern of associated proteins, this work avenues a concept to develop more specific inhibitors of OC cell growth and drug leads.

Use of milk amyloid A in the diagnosis of subclinical mastitis in dairy ewes.

Subclinical mastitis (SM) is one of the most important diseases affecting dairy ewes worldwide, with negative impact on the animal health, farm income and public health. Animals with SM often remain untreated because the disease may not be revealed. Increase in somatic cell count (SCC) and positive bacteriology for mastitis pathogens in milk samples are indicative of SM but the evidence of only one of these alterations must suggest an uncertain SM (UM). UM is defined when positive bacteriological examination (Latent-SM) or SCC>500 000 cells/ml (non-specific-SM) are detected in milk. Nevertheless, SCC and bacteriological examination are expensive, time consuming and are not yet in use at the farm level in dairy ewes. Recently, a sensitive acute phase protein, amyloid A, displaying multiple isoforms in plasma and different body fluids including mammary secretion (milk amyloid A-MAA), has been investigated as a marker of mastitis in cows and, in a few studies, in sheep. The aim of this trial was to compare the concentration of MAA of single udder-halves in ewes with healthy udder-halves (HU-control group) and naturally occurring subclinical mastitis, both confirmed (SM group) and uncertain (UM groups: Latent-SM and non-specific-SM), for monitoring udder health. The reliability of a specific ELISA kit for the measurement of MAA was also tested. During a 3-month trial period, 153 udder halves were assigned to the experimental groups based on their health status: 25 with SM, 40 with UM (11 with latent-SM and 29 with non-specific-SM) and 88 HU. SCC and bacteriological analysis were performed to establish the control and subclinical mastitis groups. MAA concentrations in milk samples were measured using a specific commercially milk ELISA kit. The data were submitted to statistical analysis. Significant (P<0·05) differences among the groups SM, non-specific-SM and HU were detected with the SM having the highest level and HU the lowest. MAA concentration is affected by the udder health status and is a useful indicator of subclinical mastitis and increased SCC in sheep.

Synthesis and separation of the enantiomers of the neuropeptide S receptor antagonist (9R/S)-3-oxo-1,1-diphenyl-tetrahydro-oxazolo[3,4-a]pyrazine-7-carboxylic acid 4-fluoro-benzylamide (SHA 68).

This study reports the synthesis, chromatographic separation, and pharmacological evaluation of the two enantiomers of the neuropeptide S receptor (NPSR) antagonist (9R/S)-3-oxo-1,1-diphenyl-tetrahydro-oxazolo[3,4-a]pyrazine-7-carboxylic acid 4-fluoro-benzylamide (SHA 68). The (9R)-3-oxo-1,1-diphenyl-tetrahydro-oxazolo[3,4-a]pyrazine-7-carboxylic acid 4-fluoro-benzylamide (compound 10) and (9S)-3-oxo-1,1-diphenyl-tetrahydro-oxazolo[3,4-a]pyrazine-7-carboxylic acid 4-fluoro-benzylamide (compound 10a) were synthesized and their purity assessed by chiral chromatography. The absolute configuration of the enantiomer 10 has been assigned from the crystal structure of the corresponding (S)-phenyl ethyl amine derivative 8. Calcium mobilization studies performed on cells expressing the recombinant NPSR demonstrated that compound 10 is the active enantiomer while the contribution of 10a to the NPSR antagonist properties of the racemic mixture is negligible.

Pharmacological profile and antiparkinsonian properties of the novel nociceptin/orphanin FQ receptor antagonist 1-[1-cyclooctylmethyl-5-(1-hydroxy-1-methyl-ethyl)-1,2,3,6-tetrahydro-pyridin-4-yl]-3-ethyl-1,3-dihydro-benzoimidazol-2-one (GF-4).

In this study we provided a pharmacological characterization of the recently synthesized nociceptin/orphanin FQ (N/OFQ) peptide receptor (NOP) antagonist 1-[1-Cyclooctylmethyl-5-(1-hydroxy-1-methyl-ethyl)-1,2,3,6-tetrahydro-pyridin-4-yl]-3-ethyl-1,3-dihydro-benzoimidazol-2-one (GF-4) and investigated its antiparkinsonian properties. GF-4 inhibited N/OFQ binding to CHO(hNOP) cell membranes (pK(i) 7.46), and antagonized N/OFQ effects in a calcium mobilization assay and electrically stimulated isolated tissues (pK(B) 7.27-7.82), showing a approximately 5-fold selectivity over classical opioid receptors. In vivo, GF-4 dually modulated stepping activity in wild-type mice, causing facilitation in the 0.01-10mg/kg dose range and inhibition at 30mg/kg. These effects were mediated by NOP receptors since GF-4 was ineffective in NOP receptor knock-out mice. Antiparkinsonian properties of GF-4 were investigated in 6-hydroxydopamine hemilesioned rats. GF-4 ameliorated akinesia, bradykinesia and overall gait ability in the 0.1-10mg/kg dose range, but inhibited motor activity at 30mg/kg. To investigate the circuitry underlying motor facilitating and inhibitory effects of GF-4, microdialysis coupled to behavioral testing (akinesia test) was performed. An anti-akinetic dose of GF-4 (1mg/kg) reduced glutamate (GLU) and enhanced GABA release in SNr, while the pro-akinetic dose of GF-4 (30mg/kg) evoked opposite effects. Moreover, the anti-akinetic dose of GF-4 reduced GABA and increased GLU release in ventro-medial thalamus, the pro-akinetic dose decreasing GABA without affecting GLU release in this area. We conclude that GF-4 is an effective NOP receptor antagonist able to attenuate parkinsonian-like symptoms in vivo via inhibition of the nigro-thalamic pathway.

Further studies on the pharmacological profile of the neuropeptide S receptor antagonist SHA 68.

Neuropeptide S (NPS) regulates various biological functions by selectively activating the NPS receptor (NPSR). Previous studies demonstrated that the non-peptide molecule SHA 68 acts as a selective NPSR antagonist. In the present study the pharmacological profile of SHA 68 has been further investigated in vitro and in vivo. In cells expressing the mouse NPSR SHA 68 was inactive per se up to 10microM while it antagonized NPS-stimulated calcium mobilization in a competitive manner showing a pA(2) value of 8.06. In the 10-50mg/kg range of doses, SHA 68 counteracted the stimulant effects elicited by NPS, but not those of caffeine, in mouse locomotor activity experiments. In the mouse righting reflex assay SHA 68 fully prevented the arousal-promoting action of the peptide. The anxiolytic-like effects of NPS were slightly reduced by SHA 68 in the mouse open field, fully prevented in the rat elevated plus maze and partially antagonized in the rat defensive burying paradigm. Finally, SHA 68 was found poorly active in antagonizing the NPS inhibitory effect on palatable food intake in rats. In all assays SHA 68 did not produce any effect per se. In conclusion, the present study demonstrated that SHA 68 behaves as a selective NPSR antagonist that can be used to characterize the in vivo actions of NPS. However the usefulness of this research tool is limited by its poor pharmacokinetic properties.