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Vaccinia virus decreases major histocompatibility complex (MHC) class II antigen presentation, T-cell priming, and peptide association with MHC class II.

Vaccinia virus (VACV) is the current live virus vaccine used to protect humans against smallpox and monkeypox, but its use is contraindicated in several populations because of its virulence. It is therefore important to elucidate the immune evasion mechanisms of VACV. We found that VACV infection of antigen-presenting cells (APCs) significantly decreased major histocompatibility complex (MHC) II antigen presentation and decreased synthesis of 13 chemokines and cytokines, suggesting a potent viral mechanism for immune evasion. In these model systems, responding T cells were not directly affecte

[Rapid differential diagnosis of Orthopoxviruses and Herpesviruses based upon multiplex real-time PCR].

OBJECTIVE: Variola virus, belonging to Orthopoxviridae family, is one of the most dangerous human pathogens that could be used as biological weapon. We have developed a new rapid assay, based upon Real-time PCR and melting temperatures analysis of amplicons, for the contemporary detection of Orthopoxvirus, VZV and HSV1-2, that are the most important infectious agents to be considered for differential diagnosis. METHODS: The target for detection of orthopoxvirus DNA has been a region of the crmB gene which is common to Variola virus and to other old world orthopoxviruses pathogenic for humans.

Real-time PCR assay for the detection of tanapox virus and yaba-like disease virus.

The yatapoxvirus genus contains three members: tanapox virus (TPV), yaba-like disease virus (YLDV) and yaba monkey tumor virus (YMTV), two of which (TPV and YLDV) may infect humans. However, only a very small number of patients have been diagnosed with TPV outside Africa. Given the increased international travel and the similarity of clinical signs during the early stages of a TPV/YLDV infection as compared to diseases caused by agents of potential biological warfare, such as smallpox, monkeypox, tularemia and anthrax, the rapid and reliable recognition of a TPV/YLDV infection is crucial. A re

Orthopoxvirus strains defective in surface antigen induction.

Various strains of vaccinia, variola, whitepox, monkeypox and cowpox viruses were examined for their capacity to induce a specific early antigen detectable on the surface of infected cells. The Elstree strain of vaccinia, two strains of variola minor and white variants of cowpox and monkeypox viruses lacked the capacity to induce the antigen. Variation of the parent cowpox and monkeypox viruses to white variants was always accompanied by the loss of the antigen-inducing capacity.

Natural Immunomodulatory Agents as a Complementary Therapy for Poxviruses.

Poxviruses target innate immunity mediators such as tumor necrosis factors, interleukins, interferons, complement, and chemokines. It also targets adaptive immunity such as CD4+ T cells, CD4+ T cells, and B cells. Emerging of the recent epidemic of monkeypox virus (MPXV), a zoonotic disease native to Central and Western Africa, besides the lack of permitted treatments for poxviruses infections, encouraged researchers to identify effective inhibitors to help in preventing and treating poxviruses infections. Natural bioactive components, particularly polyphenolics, are promising for creating pow…

Inhalable engineered probiotic outer membrane vesicles co-expressing multiple mpox antigens induce potent specific systemic and mucosal immune responses.

Monkeypox virus (MPXV) is transmitted through respiratory mucosa and close contact, including sexual transmission, especially among men who have sex with men (MSM). Using bioengineering, we constructed an inhaled bacterial outer membrane vesicles (OMVs) vaccine, ABM@OMV, to block MPXV transmission. This nanovaccine consists of OMVs from ΔlpxM EcN strain that co-expressing three MPXV antigens (A9R, B6R and M1R). Our results show that OMVs vector enhances antigen uptake, mediates endosomal escape, and promotes APC maturation. Due to the adjuvant activity of OMVs and the synergistic effects of mu…

Evaluation of a Zoonotic Orthopoxvirus PCR Assay for the Detection of Mpox Virus Infection.

An epidemic caused by an outbreak of mpox (formerly monkeypox) in May 2022 rapidly spread internationally, requiring an urgent response from the clinical diagnostics community. A detailed description of the clinical validation and implementation of a laboratory-developed real-time PCR test for detecting nonvariola Orthopoxvirus-specific DNA based on the newly designed RealStar Zoonotic Orthopoxvirus assay is presented. The validation was performed using an accuracy panel (n = 97) comprising skin lesion swabs in universal transport media and from mpox virus genomic DNA spiked into pooled mpox v

Rendezvous with Vaccinia Virus in the Post-smallpox Era: R&D Advances.

Smallpox was eradicated in less than 200 years after Edward Jenner's practice of cowpox variolation in 1796. The forty-three years of us living free of smallpox, beginning in 1979, never truly separated us from poxviruses. The recent outbreak of monkeypox in May 2022 might well warn us of the necessity of keeping up both the scientific research and public awareness of poxviruses. One of them in particular, the vaccinia virus (VACV), has been extensively studied as a vector given its broad host range, extraordinary thermal stability, and exceptional immunogenicity. Unceasing fundamental biologi

Epitope detection in the envelope of intracellular naked orthopox viruses and identification of encoding genes.

Monoclonal antibodies (MAbs) were generated against vaccinia virus, cowpox virus KR2 Brighton, monkeypox virus Copenhagen, or ectromelia virus. Pairwise epitope specificity studies by competition ELISAs identified 23 distinct antigenic sites in 19 different orthopox virus strains. Six epitopes were completely independent of each other, and 17 closely related antigenic sites formed three separate epitope complexes. As shown by immunogold electron microscopy (ELMI), all MAbs reacted with epitopes in the envelope of intracellular naked virus, 16 MAbs recognized proteins of 32, 30, 16 or 14 kDa in…

Addressing the risk of monkeypox exposure during gastrointestinal endoscopy.

The current monkeypox virus (MPV) outbreak is now a global health concern. MPV, a zoonotic double-stranded DNA virus, may be transmitted from human to human or by contaminated surfaces. Understanding the clinical characteristics and risks of MPV transmission are important, especially for health care workers, who may unknowingly encounter the virus while fulfilling their clinical responsibilities. The World Health Organization has recognized this orthopoxvirus outbreak as a public health emergency and the knowledge gaps regarding MPV's transmission are likely to have contributed to its spread. …

A review of compounds exhibiting anti-orthopoxvirus activity in animal models.

Several animal models using mice (most frequently), rabbits, or monkeys have been used to identify compounds active against orthopoxvirus infections. The treatment of vaccinia virus infections has been well studied in models involving infection of scarified skin or eyes, or resulting from intravenous, intraperitoneal, intracerebral, or intranasal virus inoculation. Cowpox virus has been used in intranasal or aerosol infection studies to evaluate the treatment of lethal respiratory infections. Rabbitpox, monkeypox, and variola viruses have been employed to a lesser extent than the other viruses

Survival of viruses in water microcosms.

Human enteric viruses and emerging viruses such as severe acute respiratory syndrome coronavirus 2, influenza virus and monkeypox virus, are frequently detected in wastewater. Human enteric viruses are highly persistent in water, but there is limited information available for non-enteric viruses. The present study evaluated the stability of hepatitis A virus (HAV), murine norovirus (MNV), influenza A virus H3N2 (IAV H3N2), human coronavirus (HCoV) 229E, and vaccinia virus (VACV) in reference water (RW), effluent wastewater (EW) and drinking water (DW) under refrigeration and room temperature c…

The two-dose MVA-BN mpox vaccine induces a nondurable and low avidity MPXV-specific antibody response.

UNLABELLED: The 2022 global outbreak of clade IIb mpox was the first major outbreak of mpox outside of African nations. To control the outbreak, public health officials began vaccination campaigns using the third-generation orthopoxvirus vaccine modified vaccinia Ankara from Bavarian Nordic (MVA-BN). Prior to this outbreak, the durability of monkeypox virus (MPXV)-specific immunity induced by MVA-BN was poorly understood. In 2022, we launched the New York City Observational Study of Mpox Immunity (NYC OSMI, NCT05654883), a longitudinal study of 171 participants comprising MVA-BN vaccines and m…

Bioterrorism: is it a real threat?

The Geneva Protocol of 1925 commits the signatory nations to refraining from the use of biological weapons. However, the terrorist assaults of September 2001 and, subsequently, the anthrax-containing letters are cause for great concerns: new threats to the security of nations are expected, as terrorist organizations seem to increasingly explore novel ways of spreading terror. In this context, naturally emerging diseases such as SARS, monkeypox or West Nile fever assume new importance because it is difficult to distinguish between natural epidemics and possible bioweapon assaults. Great efforts

Viral dynamics in patients with monkeypox infection: a prospective cohort study in Spain.

BACKGROUND: Monkeypox DNA has been detected in skin lesions, saliva, oropharynx, urine, semen, and stool of patients infected during the 2022 clade IIb outbreak; however, the viral dynamics within these compartments remain unknown. We aimed to characterise the viral load kinetics over time in various parts of the body. METHODS: This was an observational, prospective, multicentre study of outpatients diagnosed with monkeypox in two hospitals and two sexual health clinics in Spain between June 28, 2022, and Sept 22, 2022. Men and women aged over 18 years were eligible if they reported having sy

OpenRecombinHunt: Automatic detection of recombination in publicly available viral sequences.

Zoonotic transmission and viral spillover events pose severe threats to public health, as underscored by recent pandemics. Mitigating these risks requires robust genomic surveillance systems, supported by the growing availability of openly accessible viral genome sequences through dedicated resources such as NCBI Virus and Nextstrain/Pathogens. This wealth of data highlights the need for lightweight, automated computational tools to monitor viral evolution and spread. OpenRecombinHunt extends our previously published RecombinHunt method, originally developed to identify recombinant SARS-CoV-2

Protective Human Anti-Poxvirus Monoclonal Antibodies Are Generated from Rare Memory B Cells Isolated by Multicolor Antigen Tetramers.

Smallpox, an epidemic disease caused by Orthopoxvirus variola, was eradicated worldwide through immunization. The immunization against smallpox was discontinued in 1980. However, incidences of monkeypox virus infection in humans have occurred sporadically, and there is also great fear that engineered forms of poxvirus could be used as biological weapons. Therefore, monoclonal antibodies against poxvirus are urgently needed for the detection and treatment of poxvirus infection. The vaccinia virus' extracellular envelope protein A33 is a potential candidate for a subunit vaccine. We used multi-f…

Diversity in the acute CD8 T cell response to vaccinia virus in humans.

Orthopoxviruses have complex proteomes. Infection provokes a brisk CD8 response, which is required in some systems for recovery from primary infection. Little is known concerning the Ags and epitopes recognized by CD8 T cells. We examined the fine specificity of cloned and bulk human vaccinia-specific CD8 CTL by expressing polypeptide fragments from a library of vaccinia genomic DNA. This epitope discovery method emphasizes virus-specific biological activity, as the responder cells are all reactive with whole vaccinia virus. Sixteen novel epitopes, restricted by several HLA A and B alleles, we

Адамантановые производные как потенциальные ингибиторы белка и воспроизводства оксивируса P37. Проектирование, синтез и антивирусная активность.

В настоящее время, по данным ВОЗ, оспа, вызванная вирусом вариолы, относящимся к семейству оксивирусов, полностью искоренена. Однако другие представители оксивирусов, такие, как вирус вакцины, вирус коровьей железы, вирус эктомелии, вирус обезьянопокса, вирус мышипокса и другие, остаются в естественной среде и могут заразить как животных, так и людей. Патогенные организмы животных, относящиеся к категории с высоким эпидемическим риском, уже вызвали несколько вспышек среди людей и могут, в неблагоприятном сочетании обстоятельств, вызвать не только эпидемию, но и пандемию. Несмотря на то, что су

Совпадение в аннотации оригинала
Currently, smallpox, caused by the variola virus belonging to the poxvirus family, has been completely eradicated according to the WHO. However, other representatives of poxviruses, such as vaccinia virus, cowpox virus, ectromelia virus, monkeypox virus, mousepox virus and others, remain in the natural environment and can infect both animals and humans. The …