Lack of antiviral activity of ivermectin against foot-and-mouth disease virus serotype O in BALB/c mice.

Ivermectin is an FDA approved drug and showed in vitro antiviral activity against different serotypes of Foot-and-mouth disease virus (FMDV). We here assessed the effect of ivermectin in 12 day old female BALB/c mice infected with 50LD50 FMDV serotype O intraperitoneally. Initially FMDV was adopted on 3-day old BALB/c mice by blind passages. After successful adaptation of virus mice showed hind limb paralysis. Mice were divided in 6 different groups and each group has 6 mice. Ivermectin was given at clinically prescribed dose of 500 µg/kg subcutaneously at different time interval. Ivermectin was given at 0 h post infection (hpi) and 12 hpi. Moreover we compared commercially available ivermectin with purified ivermectin preparation in sterilized DMSO. Viral load was evaluated through RT-qPCR and ELISA in different groups. Results showed that positive control and negative control has CT-value 26.28 and 38 respectively. Treated groups at 0hpi, 12hpi, purified ivermectin and pre-post treatment group has CT values 24.89, 29.44, 27.26 and 26.69 respectively that showed there was no significant reduction in virus load in treated groups as compare to positive control. In histopathology of lung tissue perialveolar capillaries were congested and alveoli were altelactic. Some emphysema was seen in alveoli and mild thickening in the alveolar wall was observed. In the alveolar epithelium mononuclear cells infiltration was seen. There was discoloration haemorrhages and enlargement of heart. Degeneration, fragmentation and loss of sarcoplasm were seen in the cardiac muscle fibers. Above results showed that ivermectin did not lessen lung and heart viral load. This study contributes that ivermectin does not have a significant antiviral effect when used in mice against FMDV serotype O, according to a growing body of research.

Antiviral potential of ivermectin against foot-and-mouth disease virus, serotype O, A and Asia-1.

Each year, foot-and-mouth disease leads to enormous economic losses to the livestock industry. Currently, the killed whole virus is widely using to control FMD. However, vaccination is constrained by lack of or incomplete protection. Therefore, along with vaccination, we need to find the antivirals against FMD. This study was conducted to investigate the antiviral potential of ivermectin against multiple serotypes of FMDV. Initially, an MTT assay was performed on the BHK-21 cell line to determine assay ivermectin cytotoxicity. Viral inhibition assays using the non-cytotoxic concentration of ivermectin were performed to check the antiviral potential of ivermectin on different stages of virus replication. At 2.5 µM and 5 µM concentrations of ivermectin, the virus titer was reduced significantly (p < 0.001) by two to three log in all three strains of viruses at both non-toxic concentrations (2.5 and 5 µM). The virus titer in strain O control was 106.0 TCID50/0.1 mL and was reduced to 104.1 TCID50/0.1 mL at a concentration of 2.5 µM and 103.10 TCID50/0.1 mL at 5 µM concentration. In the case of strain Asia-1, the virus titer was reduced to 103.8 TCID50/0.1 mL at 2.5 µM and 103.01TCID50/0.1 mL at 5 µM concentration. The titer of strain A was reduced from 105.8 TCID50/0.1 mL to 103.9 TCID50/0.1 mL at 2.5 µM concentration and 103.1 TCID50/0.1 mL at 5 µM concentration. Moreover, the virus titer was reduced more at the replication stage as compared to attachment and entry stages. This study showed the in vitro anti-FMDV potential of ivermectin for the first time and predicted its potential use against FMDV infections.

An in vitro antiviral activity of iodine complexes against SARS-CoV-2.

Since the emergence of COVID-19 pandemic in China in late 2019, scientists are striving hard to explore non-toxic, viable anti-SARS-CoV-2 compounds or medicines. We determined In vitro anti-SARS-CoV-2 activity of oral formulations (syrup and capsule)of an Iodine-complex (Renessans). First, cell cytotoxicity of Renessans on the Vero cells was determined using MTT assay. Afterwards, the antiviral activity of Renessans was determined using viral inhibition assays and TCID50. For this, nontoxic concentrations of the Renessans were used. The results showed that Renessans is nontoxic to the cells up to 50 µg/mL. At 1.5 µg/mL concentration, SARS-CoV-2 production was significantly reduced to 101.43 TCID50 and 101.58 TCID50 for the syrup and capsule, respectively, as compare to virus infected control cells 106.08 TCID50 and we found the dose dependent inhibition of virus replication in the presence of Renessans. Renessans inhibited SARS-CoV-2 with an EC50 value of 0.425 µg/mL and 0.505 µg/mL for syrup and capsule, respectively. Furthermore, there was no virus detected at concentration of 50 µg/mL of Renessans. This study indicates that Renessans, containing iodine, have potential activity against SARS-CoV-2 which needs to be further investigated in human clinical trials.

In silico analysis of four structural proteins of aphthovirus serotypes revealed significant B and T cell epitopes.

Foot and Mouth disease (FMD) is economically devastating, highly contagious transboundry viral disease of livestock with 100% morbidity, rapid spread and severe production losses in animals. The FMDV has seven different serotypes. There is no vaccine that can protect animals from all serotypes. Hence, it is need of the day to develop a vaccine that protects animals from hetrologous challenge. In this study, we used immunoinformatics approach to find T and B-cell epitopes that will help to construct a universal vaccine for FMDV. For this purpose, first we constructed a consensus sequence for four structural proteins (VP1, VP2, VP3 and VP4) of aphthovirus for seven serotypes (A, O, C, Asia1, SAT1, SAT2 and SAT3). Various computational tools were used to perform multiple sequence alignment to identify the conserved regions, generation of consensus sequence through conserved regions, structures prediction and finally prediction of B and T cell epitopes. We predicted 5 B cell and 18 T cell epitopes. Finally a GPGPG spacer was used to join these epitopes to decrease binding affinity around the core binding regions. Hence, our study identified the epitopes which can be used to develop cross protective vaccines against all the fatal strains of Aphthovirus which can easily protect all the serotypes. Though, successful In vivo and In vitro studies are required to determine the genuine strength of our predicted epitopes against the fatal strains of Aphthovirus.

Prediction of conserved sites and domains in glycoproteins B, C and D of herpes viruses.

Glycoprotein B (gB), C (gC) and D (gD) of herpes simplex virus are implicated in virus adsorption and penetration. The gB, gC and gD are glycoproteins for different processes of virus binding and attachment to the host cells. Moreover, their expression is necessary and sufficient to induce cell fusion in the absence of other glycoproteins. Egress of herpes simplex virus (HSV) and other herpes viruses from cells involves extensive modification of cellular membranes and sequential envelopment, de-envelopment and re-envelopment steps. Viral glycoproteins are important in these processes, and frequently two or more glycoproteins can largely suffice in any step. Hence, we target the 3 important glycoproteins (B, C and D) of eight different herpes viruses of different species. These species include human (HSV1 and 2), bovine (BHV1), equine (EHV1 and 4), chicken (ILT1 and MDV2) and pig (PRV1). By applying different bioinformatics tools, we highlighted the conserved sites in these glycoproteins which might be most significant regarding attachment and infection of the viruses. Moreover the conserved domains in these glycoproteins are also highlighted. From this study, we will able to analyze the role of different viral glycoproteins of different species during herpes virus adsorption and penetration. Moreover, this study will help to construct the antivirals that target the glycoproteins of different herpes viruses.

Role of Rab GTPases in HSV-1 infection: Molecular understanding of viral maturation and egress.

Most enveloped viruses exploit complex cellular pathways for assembly and egress from the host cell, and the large DNA virus Herpes simplex virus 1 (HSV-1) makes no exception, hijacking several cellular transport pathways for its glycoprotein trafficking and maturation, as well as for viral morphogenesis and egress according to the envelopment, de-envelopment and re-envelopment model. Importantly Rab GTPases, widely distributed master regulators of intracellular membrane trafficking pathways, have recently being tightly implicated in such process. Indeed, siRNA-mediated genetic ablation of specific Rab proteins differently affected HSV-1 production, suggesting a complex role of different Rab proteins in HSV-1 life cycle. In this review, we discuss how different Rabs can regulate HSV-1 assembly/egress and the potential therapeutic applications of such findings for the management of HSV-1 infections.

Alpha toxin production potential and antibiotic resistance patterns of clostridium perfringens isolates from meat samples.

Objective: This research aimed to analyze the prevalence, molecular characteristics, toxinotyping, alpha toxin production potential, and antibiotic resistance pattern of Clostridium perfringens (C. perfringens) isolates in meat samples collected from various sources. Methods: Sixty meat samples were screened for alpha toxin using Enzyme-Linked Immunosorbent Assay (ELISA), revealing a positivity rate of 13.3%, predominantly in raw poultry meat. Subsequent culturing on Perfringens agar identified nine samples harboring characteristic C. perfringens colonies, primarily isolated from raw poultry meat. Molecular confirmation through 16S rRNA gene amplification and sequencing authenticated twelve isolates as C. perfringens, with nine strains exhibiting genetic resemblance to locally isolated strains. Toxinotyping assays targeting alpha toxin-specific genes confirmed all nine isolates as type A C. perfringens, with no detection of beta or epsilon toxin genes. Hemolytic assays demonstrated varying alpha toxin production potentials among isolates, with accession number OQ721004.1 displaying the highest production capacity. Moreover, antibiotic resistance profiling revealed multi-drug resistance patterns among the isolates. Results: The study identified distinct clusters within C. perfringens strains, indicating variations. Phylogenetic analysis delineated genetic relatedness among strains, elucidating potential evolutionary paths and divergences. Conclusion: The findings underscore the need for robust surveillance and control measures to mitigate the risk of C. perfringens contamination in meat products, particularly in raw poultry meat. Enhanced monitoring and prudent antimicrobial stewardship practices are warranted in both veterinary and clinical settings to address the observed antibiotic resistance profiles and prevent foodborne outbreaks.

Evaluation of genotoxic effect via expression of DNA damage responsive gene induced by ivermectin on MDBK cell line.

Ivermectin (IVM) is an anti-parasitic drug which is used for treating parasitic infestations. It has been used in humans for treating intestinal strongyloidiasis and onchocerciasis however, currently researchers are investigating its potential for treating coronavirus SARS-CoV-2. Due to its broad-spectrum activities, IVM is being used excessively in animals which has generated an interest for researchers to investigate its toxic effects. Cytotoxic and genotoxic effects have been reported in animals due to excessive usage of IVM. Therefore, this study aims to evaluate the cytotoxic and genotoxic effects of IVM on the Madin-Darby-Bovine-Kidney (MDBK) cell line by examining the expression of a DNA damage-responsive gene (OGG1). Cytotoxicity of IVM was tested using an assay (MTT 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide), whereas the genotoxicity was evaluated using comet assay along with micronucleus assay. Moreover, the gene expression of DNA damage response gene (OGG1) was measured by qRT-PCR, after extraction of RNA from the MDBK cell line using the TRIzol method and its conversion to cDNA by reverse-transcriptase PCR. During the experiment, cell viability percentage was measured at different doses of IVM i.e., 25%, 50%, 75%, along with LC50/2, LC50 and LC50*2. It was observed that the gene expression of OGG1 increased as the concentration of IVM increased. It was concluded that IVM has both cytotoxic and genotoxic effects on the MDBK cell line. Furthermore, it is recommended that studies related to the toxic effects of IVM at molecular level and on other model organisms should be conducted to combat its hazardous effects.

Molecular Characterization of UL50 (dUTPase) Gene of Bovine Herpes Virus 1.

Bovine herpes virus -1 (BoHV-1) infection leads to upper respiratory tract infection, conjunctivitis and genital disorders in cattle. To control BoHV-1, it is important to understand the role of viral proteins in viral infection. BoHV-1 has several gene products to help in viral replication in infected cell. One such gene is deoxyuridine triphosphate nucleotidohydrolase (dUTPase) also known as UL50. In this study, we analyzed the amino acid sequence of UL50 (dUTPase) using bioinformatics tools and found that it was highly conserved among herpesvirus family. Then, it was cloned and expressed in Escherichia coli Rosetta (DE3), induced by isopropy1-b-D-thiogalactopyranoside (IPTG) and the recombinant UL50 protein was purified to immunize rabbits for the preparation of polyclonal antiserum. The results indicated that the UL50 gene of BoHV-1 was composed of 978 nucleotides, which encoded 323 amino acids. Western blot analysis revealed that polyclonal sera against UL50 reacted with a band of 34 kDa. Furthermore, immunofluorescence assay showed that UL50 localized in the cytoplasmic area. Taken together, UL50 was successfully cloned, expressed and detected in BoHV-1-infected cells and was localized in the cytoplasm to help in the replication of BoHV-1 in infected cells.

The immunogenicity and efficacy of acommercially available Infectious Bovine Rhinotracheitis (IBR) virus vaccine against a Pakistani field IBR strain.

Infectious bovine rhinotracheitis (IBR) is a highly communicable disease of cattle and wild ruminants that is caused by Bovine alphaherpesvirus 1 (BoHV­1). For IBR control, several developed countries have adopted the immunization and eradication programs focusing on IBR­positive animals. In Pakistan, livestock producers are importing commercially available vaccine of BoHV­1, but no studies on the efficacy of these commercial vaccines against local isolates are available. Therefore, the present study was aimed to evaluate the efficacy of a commercially available vaccine of BoHV­1 against local field isolates of virus. The rabbit model was used and the vaccine was evaluated for immunogenicity and protection after challenge with a highly virulent strain of a field virus. The immune response was measured by virus neutralization titers (VNT). This vaccine induced a humoral response in rabbits but that was not sufficient to completely protect the vaccinated animals against the wild­type BoHV­1 strain challenge. While a low virus titer compared to control rabbits was observed in the vaccinated rabbits (p<0.05), there was no sterilizing immunity or freedom from infection. However, complete freedom from disease, for example, the absence of pyrexia was noticed in the vaccinated group. In conclusion, the present study demonstrated that imported vaccine stock provoked only a partial protection against indigenous isolated of BoHV­1. However, tests performed on rabbits are preliminary, as only those performed on the source species can determine more reliable results.