Studies on interferon production and interferon sensitivity of different strains of Newcastle disease virus

Interferon production by Viral, Bacterial & Yeast system: A comparative overview in 2023

Interferons play a critical role in the innate immune response against several infections and play a key role in the control of a variety of viral and bacterial infectious diseases such as hepatitis, covid-19, cancer, and multiple sclerosis. Therefore, natural or synthetic IFN production is important and had three common methods, including bacterial fermentation, animal cell culture, and recombinant nucleic acid technology. However, the safety, purity, and accuracy of the most preferred INF production systems have not been extensively studied. This study provides a comprehensive comparative overview of interferon production in various systems that include viral, bacterial, yeast, and mammalian. We aim to determine the most efficient, safe, and accurate interferon production system available in the year 2023. The mechanisms of artificial interferon production were reviewed in various organisms, and the types and subtypes of interferons produced by each system were compared. Our analysis provides a comprehensive overview of the similarities and differences in interferon production and highlights the potential for developing new therapeutic strategies to combat infectious diseases. This review article offers the diverse strategies used by different organisms in producing and utilizing interferons, providing a framework for future research into the evolution and function of this critical immune response pathway.

A novel role of classical swine fever virus E(rns) glycoprotein in counteracting the newcastle disease virus (NDV)-mediated IFN-beta Induction

E(rns) is an envelope glycoprotein of classical swine fever virus (CSFV) and has an unusual feature of RNase activity. In the present study, we demonstrate that E(rns) counteracts Newcastle disease virus (NDV)-mediated induction of IFN-beta. For this purpose, E(rns) fused to the enhanced green fluorescent protein (EGFP) was transiently expressed in porcine kidney 15 (PK15) cells. In luciferase activity assay, E(rns)-EGFP was found to prevent IFN-beta promoter-driven luciferase expression and block the induction of IFN-beta promoter mediated by NDV in a dosedependent manner. Through IFN-specific semi-quantitative RT-PCR detection, obvious decrease of IFN-beta mRNA in NDV-infected PK15 cells was observed in the presence of E(rns)-EGFP. In contrast, EGFP alone showed none of this block capacity. In addition, E(rns)-EGFP mutations with RNase inactivation were also found to block NDV-mediated induction of IFN-beta. These evidences establish a novel function for CSFV E(rns) glycoprotein in counteraction of the IFN-beta induction pathway.

p53-independent endoplasmic reticulum stress-mediated cytotoxicity of a Newcastle disease virus strain in tumor cell lines

While Newcastle disease virus (NDV) causes serious infections in birds, it is apparently nonpathogenic in mammalian species, including humans. Previous observations and small-scale clinical trials indicated that NDV exerts oncolytic effects. Isolates of NDV were found to have selective affinity to transformed cells. We previously showed that the attenuated NDV strain MTH-68/H causes apoptotic cell death in cultures of PC12 rat pheochromocytoma cells. The aim of the present study was to extend MTH-68/H cytotoxicity testing with human tumor cell lines and to analyze certain biochemical aspects of its oncolytic effect. MTH-68/H was found to be able to kill a wide range of transformed cells by apoptosis. While caspase-8 and caspase-9 are not involved in MTH-68/H-induced apoptosis, activation of caspase-3 and caspase-12 was detected in virus-infected PC12 cells. A human glioblastoma cell line with repressible expression of the p53 protein did not show any difference in MTH-68/H sensitivity in its p53-expressing and p53-depleted states, indicating that the apoptotic process induced by MTH-68/H does not depend on p53. Apoptosis was accompanied by virus replication in two tumor cell lines tested (PC12 cells and HeLa human cervical cells), and signs of endoplasmic reticulum stress (phosphorylation of protein kinase R-like endoplasmic reticulum kinase and eIF2alpha) were also detected in transformed cells. In contrast, proliferation of nontransformed mouse and rat fibroblast cell lines and human primary fibroblasts was not affected by MTH-68/H treatment. MTH-68/H thus selectively kills tumor cell cultures by inducing endoplasmic reticulum stress leading to p53-independent apoptotic cell death.

Differentially regulated interferon response determines the outcome of Newcastle disease virus infection in normal and tumor cell lines

Newcastle disease virus (NDV) is a negative-strand RNA virus with oncolytic activity against human tumors. Its effectiveness against tumors and safety in normal tissue have been demonstrated in several clinical studies. Here we show that the spread of NDV infection is drastically different in normal cell lines than in tumor cell lines and that the two cell types respond differently to beta interferon (IFN-beta) treatment. NDV rapidly replicated and killed HT-1080 human fibrosarcoma cells but spread poorly in CCD-1122Sk human skin fibroblast cells. Pretreatment with endogenous or exogenous IFN-beta completely inhibited NDV replication in normal cells but had little or no effect in tumor cells. Thus, the outcome of NDV infection appeared to depend on the response of uninfected cells to IFN-beta. To investigate their differences in IFN responsiveness, we analyzed and compared the expression and activation of components of the IFN signal transduction pathway in these two types of cells. The levels of phosphorylated STAT1 and STAT2 and that of the ISGF3 complex were markedly reduced in IFN-beta-treated tumor cells. Moreover, cDNA microarray analysis revealed significantly fewer IFN-regulated genes in the HT-1080 cells than in the CDD-1122Sk cells. This finding suggests that tumor cells demonstrate a less-than-optimum antiviral response because of a lesion in their IFN signal transduction pathway. The rapid spread of NDV in HT-1080 cells appears to be caused by their deficient expression of anti-NDV proteins upon exposure to IFN-beta.

Newcastle disease virus V protein is associated with viral pathogenesis and functions as an alpha interferon antagonist

Newcastle disease virus (NDV) edits its P gene by inserting one or two G residues at the conserved editing site (UUUUUCCC, genome sense) and transcribes the P mRNA (unedited), the V mRNA (with a +1 frameshift), and the W mRNA (with a +2 frameshift). All three proteins are amino coterminal but vary at their carboxyl terminus in length and amino acid composition. Little is known about the role of the V and W proteins in NDV replication and pathogenesis. We have constructed and recovered two recombinant viruses in which the expression of the V or both the V and W proteins has been abolished. Compared to the parental virus, the mutant viruses showed impaired growth in cell cultures, except in Vero cells. However, transient expression of the carboxyl-terminal portion of the V protein enhanced the growth of the mutant viruses. In embryonated chicken eggs, the parental virus grew to high titers in embryos of different gestational ages, whereas the mutant viruses showed an age-dependent phenomenon, growing to lower titer in more-developed embryos. An interferon (IFN) sensitivity assay showed that the parental virus was more resistant to the antiviral effect of IFN than the mutant viruses. Moreover, infection with the parental virus resulted in STAT1 protein degradation, but not with the mutant viruses. These findings indicate that the V protein of NDV possesses the ability to inhibit alpha IFN and that the IFN inhibitory function lies in the carboxyl-terminal domain. Pathogenicity studies showed that the V protein of NDV significantly contributes to the virus virulence.

Phylogenetic analysis of Newcastle disease virus genotypes isolated in Japan

We genetically analyzed field isolates of the Newcastle disease (ND) virus isolated in Japan from 1930 to 2001. The coding region of the fusion protein was amplified by reverse transcriptase PCR and directly sequenced. Phylogenetic analysis revealed the presence of viruses belonging to six of the eight known genotypes. It can be concluded from this study that ND outbreaks in Japan have been of multiple etiologies. [All sequences used in this study were sent to DDBJ and assigned accession numbers AB 070382 to AB 074042.]

Identification and grouping of Newcastle disease virus strains by restriction site analysis of a region from the F gene

A 75% region of the F gene (between nucleotides 334 and 1682) of Newcastle disease virus (NDV) RNA was amplified by reverse transcription polymerase chain reaction (RT-PCR). PCR products were cleaved by three restriction endonucleases and the positions of thirty cleavage sites were mapped in more than 200 NDV strains. Restrictions site analysis established six major groups of NDV isolates and unique fingerprints of vaccine strains. Group I comprised lentogenic strains isolated mainly from waterfowl with some from chickens. "Old" (prior to 1960s) North American isolates of varying virulence including lentogenic and mesogenic vaccine strains belonged to group II. Group III included two early isolates from the Far East. Early European strains (Herts 33 and Italien) of the first panzootic (starting in the late 1920s) and their descendants with some modifications were placed into group IV. NDV strains isolated during the second panzootic of chickens (starting in the early 1960s) were classified into two groups. Group V included strains originating in imported psittacines and in epizootics of chickens in the early 1970s. Group V1 comprised strains from the Middle East in the late 1960s and later isolates from Asia and Europe. Pigeon paramyxovirus-1 strains that were responsible for the third panzootic formed a distinct subgroup in group V1. Our grouping of NDV strains has confirmed group differences established by monoclonal antibodies. It is concluded that restriction site analysis of F gene PCR amplicons is a relatively fast, simple and reliable method for the differentiation and identification of NDV strains.

More than one component of the Newcastle disease virus particle is capable of interferon induction

The interferon (IFN)-inducing capacities of intact NDV virions, beta-propiolactone-inactivated particles and several structural components were compared, using human PBML as the IFN producing cells. Intact and inactivated virions as well as the nucleocapsid fraction did not differ significantly in their IFN-inducing capacity. In contrast, genomic RNA as well as M protein fraction and envelopes induced IFN titres to a level of about 10% of those achieved with virions. NDV-induced IFN production could be blocked specifically by incubation with polyclonal anti-NDV-monoclonal antibodies (mAbs) and with two of three anti-HN-mAbs, but not with anti-NDV-mAbs directed against the F, M or NP protein. In addition, IFN induction by fixed MDBK cells, expressing NDV surface proteins after infection with NDV Ulster, was inhibited by one of two anti-F-mAbs. The results suggest that the induction of IFN synthesis in human PBML is a complex process involving not only the HN protein but also the uncleaved F protein precursor, a component of the M protein fraction and--once having entered the cell--the genomic RNA.

Induction of cytokines and cytotoxicity against tumor cells by Newcastle disease virus

The use of NDV as biological adjuvant in vaccines against human cancer is still actual in several clinical treatment protocols. In this study, we have investigated in vitro-effects of Newcastle disease virus (NDV) strain 73-T on isolated mononuclear blood cells and cultured tumor cells. Cellular cytotoxicity of PBMC freshly isolated from healthy donors against tumor cells was enhanced significantly (p < 0.01) after coincubation of NDV with effector cells. NDV failed to enhance cytotoxicity of effector cells when PBMC were stimulated three days with 500 IU recombinant interleukin-2 (rIL-2) per ml prior to coincubation with the virus. No significant enhancement of cellular lysis was seen when only target cells were coincubated with NDV. As shown by depletion of various lymphocyte subsets, NK cells were the predominant mediator of lysis. Enhancement of cytotoxicity correlated with the induction of interferon-alpha (IFN-alpha) in PBMC by NDV. NDV also induced high amounts of tumor necrosis factor-alpha (TNF-alpha) in PBMC. Induction of interferon-gamma (IFN-gamma) was weak. A direct cytopathic effect (CPE) of NDV on different target cells was detected by colorimetric measurement of metabolic cell activity. The human tumor cell lines A-498, A-704, Caki-1, Caki-2, and K-562 and the fibroblast line MRC-5 showed progressive cellular destruction 48 h after infection with NDV, whereas PBMC and Daudi cells remained unaffected during the observation period. The nontransformed monkey kidney cell line CV-1 and the transformed monkey kidney cell line COS-1 were both lysed by NDV with marginal difference in time course of CPE. Our results indicate a reasonable potential of pleiotropic modifications of the immune response against tumors by NDV.

Newcastle disease vaccine (La Sota) strain specific monoclonal antibody. Brief report

Newcastle disease virus vaccine strain (La Sota) specific monoclonal antibody (La-1) was produced by immunizing mice with isolated glycoproteins of strain La Sota. This antibody was recognized only in the ELISA test in which it bound exclusively to La Sota strain out of a range of over 300 lentogenic, mesogenic and velogenic strains examined.

Prevention of metastatic spread by postoperative immunotherapy with virally modified autologous tumor cells. I. Parameters for optimal therapeutic effects

Effective anti-metastatic therapy was achieved in a mouse tumor model by combining surgery with post-operative immunotherapy using virus-modified autologous tumor cells. No therapeutic effect was observed when using for immunotherapy the nonmodified autologous tumor ESb, which is only weakly immunogenic and highly metastatic. The viral modification was achieved by infecting the tumor with an avirulent strain of Newcastle disease virus (NDV), which led to expression of viral antigens and to an increase in the tumor cells' immunogenicity. Parameters which were of decisive influence for success or failure of therapy were the time of operation of the primary tumor and the dose of virus which was admixed to a standard dose of irradiated tumor cells. There was a low dose optimum of NDV at about 100 hemagglutinating units per 25 X 10(6) tumor cells. The therapeutic effect observed was less pronounced if the virus was given separately from the tumor cells. Post-operative immunotherapy with NDV-modified tumor cells had the following therapeutic effects: (1) disappearance of micrometastases from visceral organs as ascertained by a sensitive bioassay; (2) life prolongation in virtually all animals when compared to controls (operated only); (3) cures in about 50% of the treated animals. The possible mechanism of this therapeutic effect and its potential for clinical application are discussed.

Differentiation of Newcastle disease virus strains by one-dimensional peptide mapping

One-dimensional peptide mapping was used for the differentiation of Newcastle disease virus (NDV) strains. Virions were purified in one step, and digested with Staphylococcus aureus V8 protease or chymotrypsin without prior separation of their proteins. Peptides were separated by polyacrylamide gel electrophoresis and stained with Coomassie blue. This method proved to be a simple, economic and reproducible means of differentiating NDV strains.

Interferon induction by viruses. IX. Antagonistic activities of virus particles modulated interferon production

Cells generally responded to viral inducers of interferon (IFN) by generating a dose (multiplicity of infection)-response (interferon-yield) curve which showed a good fit to a model in which the fraction of interferon-yielders corresponded to the fraction of cells infected with one or more particles. These were defined as interferon-inducing particles (IFPs). The IFN-producing capacity of cells infected with these particles was modulated upon coinfection with a second type of virus particle, those with the capacity to suppress IFN production. These were termed interferon induction-suppressing particles (ISPs). In cells coinfected with IFP and ISP the latter were dominant phenotypically. In some systems ISP activity was expressed by IFP when the latter were present at two or more particles per cell. The existence of virus particles with antagonistic activities for interferon induction provides a mechanism for regulating the production of IFN and hence the potential outcome of a virus infection.

Studies on avian infectious bronchitis virus (IBV). III. Interferon induction by and sensitivity to interferon of IBV

The induction of interferon by avian infectious bronchitis virus (IBV) and the sensitivity of IBV to interferon were studied. The results of experiments with ten IBV strains are summarized as follows. 1. All the IBV strains tested induced interferon in chick embryo (CE) cells, chicken kidney (CK) cells and embryonated eggs. The Iowa-609 strain induced about 1000 units of interferon in CE cells while the Beaudette-42 strain induced about 200 units of interferon in embryonated eggs; the interferon titers induced by other strains usually ranged from 5 to 60 units. No IBV strain induced interferon in HeLa or BHK-21 cells. 2. IBV particles inactivated by ultraviolet irradiation or by heating lost their ability to induce interferon. 3. The properties of the interferon produced in the present study are similar to those of other interferons produced in chicken cells. 4. HeLa or BHK-21 cells did not acquire resistance to virus infection, after incubation with interferon produced in CE cells. On the other hand, CK cells acquired the same degree of resistance to virus infection as CE cells after incubation with interferon produced in CE cells. 5. All the IBV strains tested were sensitive to interferon in CK cells. The sensitivities of Massachusetts-41 and Holte strains to interferon were similar to that of vesicular stomatitis virus.

Thermostability of Newcastle disease virus strains of different virulence

The thermal inactivation rate constant for infectivity of a total of 24 Newcastle disease virus (NDV) strains was determined at 50 degrees and 56 degrees C. The greater part of the examined NDV strains were found, irrespective of virulence properties, to be thermostable, since the loss of infectivity titre did not exceed 2 logarithmic orders after exposure at 50 degrees C for 60 minutes. Thermostable (I+) and thermolabile (I minus) strains with respect to infectivity were uniformly encountered among the 12 avirulent (lentogenic) and 10 fully virulent (velogenic) strains studied. Strains with both heat stable (Ha+) and heat labile (Ha minus) haemagglutinin were found in the lentogenic group, whereas haemagglutinins of all examined velogenic strains were heat stable. On the basis of I/Ha character, i.e. combination of thermosensitivity of infectivity and haemagglutinin, all examined strains could be classified into one of three categories: I minus Ha minus (8 lentogenic strains), I+Ha+ (4 lentogenic and 7 velogenic strains) and I minus Ha+ (2 mesogenic and 3 velogenic strains). The possible fourth combination, I+Ha+ minus, was not encountered among the strains studied. Determination of the I/Ha character may be helpful in clarifying the origin of a lentogenic NDV strain.

Plaque assay for avirulent (lentogenic) strains of Newcastle disease virus

Avirulent (lentogenic) strains of Newcastle disease virus form plaques on chicken embryo lung monolayers in 48 to 72 h.