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Cell Host & Microbe Dec 2022The monkeypox virus (MPXV) outbreak confirmed in May 2022 in non-endemic countries is raising concern about the pandemic potential of novel orthopoxviruses. Little is...
The monkeypox virus (MPXV) outbreak confirmed in May 2022 in non-endemic countries is raising concern about the pandemic potential of novel orthopoxviruses. Little is known regarding MPXV immunity in the context of MPXV infection or vaccination with vaccinia-based vaccines (VACV). As with vaccinia, T cells are likely to provide an important contribution to overall immunity to MPXV. Here, we leveraged the epitope information available in the Immune Epitope Database (IEDB) on VACV to predict potential MPXV targets recognized by CD4 and CD8 T cell responses. We found a high degree of conservation between VACV epitopes and MPXV and defined T cell immunodominant targets. These analyses enabled the design of peptide pools able to experimentally detect VACV-specific T cell responses and MPXV cross-reactive T cells in a cohort of vaccinated individuals. Our findings will facilitate the monitoring of cellular immunity following MPXV infection and vaccination.
Topics: Humans; Vaccinia virus; Monkeypox virus; Vaccinia; Mpox (monkeypox); Epitopes
PubMed: 36463861
DOI: 10.1016/j.chom.2022.11.003 -
Cell Host & Microbe Jun 2023Mpox represents a persistent health concern with varying disease severity. Reinfections with mpox virus (MPXV) are rare, possibly indicating effective memory responses...
Mpox represents a persistent health concern with varying disease severity. Reinfections with mpox virus (MPXV) are rare, possibly indicating effective memory responses to MPXV or related poxviruses, notably vaccinia virus (VACV) from smallpox vaccination. We assessed cross-reactive and virus-specific CD4 and CD8 T cells in healthy individuals and mpox convalescent donors. Cross-reactive T cells were most frequently observed in healthy donors over 45 years. Notably, long-lived memory CD8 T cells targeting conserved VACV/MPXV epitopes were identified in older individuals more than four decades after VACV exposure and exhibited stem-like characteristics, defined by T cell factor-1 (TCF-1) expression. In mpox convalescent donors, MPXV-reactive CD4 and CD8 T cells were more prevalent than in controls, demonstrating enhanced functionality and skewing toward effector phenotypes, which correlated with milder disease. Collectively, we report robust effector memory MPXV-specific T cell responses in mild mpox and long-lived TCF-1 VACV/MPXV-specific CD8 T cells decades after smallpox vaccination.
Topics: Humans; CD8-Positive T-Lymphocytes; Mpox (monkeypox); Smallpox; Vaccinia virus; Poxviridae
PubMed: 37236191
DOI: 10.1016/j.chom.2023.04.015 -
Advances in Experimental Medicine and... 2024The family Poxviridae is a large family of viruses with a ubiquitous distribution, subdivided into two subfamilies: Chordopoxvirinae (poxviruses of vertebrates) and... (Review)
Review
The family Poxviridae is a large family of viruses with a ubiquitous distribution, subdivided into two subfamilies: Chordopoxvirinae (poxviruses of vertebrates) and Entomopoxvirinae (poxviruses of insects). Only three species from the first subfamily, Orthopoxvirus (OPV), Molluscipoxvirus and Parapoxvirus, can infect the human being. In the paediatric population, viruses belonging to the first two subfamilies have the greatest importance. Following the eradication of smallpox in 1980, vaccination of the general population was discontinued after careful consideration of the risks and benefits. However, nearly all children and most of the world's population had little to no protection against OPV. The aim of this chapter is to review the current evidence on the aetiology, clinical manifestations, diagnosis and management of Poxviridae infections in children.
Topics: Humans; Child; Poxviridae Infections; Poxviridae; Child, Preschool; Infant; Animals
PubMed: 38801580
DOI: 10.1007/978-3-031-57165-7_13 -
Revue Medicale de Liege Jul 2022Monkeypox (MPX), is a rare endemic zoonotic disease of certain areas of Central and West Africa. Nevertheless, in recent years, several outbreaks have occurred outside...
Monkeypox (MPX), is a rare endemic zoonotic disease of certain areas of Central and West Africa. Nevertheless, in recent years, several outbreaks have occurred outside the African continent. Monkeypox usually presents with a flu-like prodromal period (fever, headache, chills, sweating) associated or followed by the appearance of lymphadenopathy and a typical skin rash. Transmission is suspected to be direct or indirect via contact with saliva, respiratory droplets or skin lesions of infected animals or more rarely of humans. The gold standard for diagnosis is the detection of MPX virus (MPXV) by PCR on skin lesion fluid. The evolution is usually favourable in 2 to 5 weeks but severe complications and sequelae are possible. In the absence of a specific treatment, the management is essentially supportive: appropriate local care, rehydration, analgesia and management of eventual complications.
Topics: Animals; Disease Outbreaks; Humans; Mpox (monkeypox); Monkeypox virus; Polymerase Chain Reaction
PubMed: 35924502
DOI: No ID Found -
Advances in Experimental Medicine and... 2024Poxviridae family includes several viruses that infecting humans usually causes skin lesions only, but in some cases their clinical course is complicated by viral... (Review)
Review
Poxviridae family includes several viruses that infecting humans usually causes skin lesions only, but in some cases their clinical course is complicated by viral pneumonia (with or without bacterial superinfections). Historically variola virus has been the poxviridae most frequently associated with the development of pneumonia with many large outbreaks worldwide before its eradication in 1980. It is still considered a biological threat for its potential in biological warfare and bioterrorism. Smallpox pneumonia can be severe with the onset of acute respiratory distress syndrome (ARDS) and death. Vaccinia virus, used for vaccination against smallpox exceptionally, in immunocompromised patients, can induce generalized (with also lung involvement) severe disease after vaccination. MPXV virus occasionally can cause pneumonia particularly in immunocompromised patients. The pathophysiology of poxviridae pneumonia is still an area of active research; however, in animal models these viruses can cause both direct damage to the lower airways epithelium and a hyperinflammatory syndrome, like a cytokine storm. Multiple mechanisms of immune evasion have also been described. The treatment of poxviridae pneumonia is mainly based on careful supportive care. Despite the absence of randomized clinical trials in patients with poxviridae pneumonia there are antiviral drugs, such as tecovirimat, cidofovir and brincidofovir, FDA-approved for use in smallpox and also available under an expanded access protocol for treatment of MPXV. There are 2 (replication-deficient modified vaccinia Ankara and replication-competent vaccinia virus) smallpox vaccines FDA-approved with the first one also approved for prevention of MPXV in adults that are at high risk of infection.
Topics: Humans; Animals; Poxviridae Infections; Antiviral Agents; Pneumonia, Viral; Poxviridae; Vaccinia virus; Smallpox; Variola virus
PubMed: 38801579
DOI: 10.1007/978-3-031-57165-7_12 -
JAMA Dermatology Oct 2022
Topics: Humans; Mpox (monkeypox); Disease Outbreaks
PubMed: 36006652
DOI: 10.1001/jamadermatol.2022.3975 -
Lancet (London, England) Jun 2022
Topics: Disease Outbreaks; Humans; Mpox (monkeypox)
PubMed: 35717977
DOI: 10.1016/S0140-6736(22)01096-0 -
Medicina Clinica Apr 2023The monkeypox virus is a virus that has 90% genomic homology with the human (smallpox), but it is naturally transmitted between different wild animal reservoirs and is... (Review)
Review
The monkeypox virus is a virus that has 90% genomic homology with the human (smallpox), but it is naturally transmitted between different wild animal reservoirs and is considered a zoonosis. Throughout the 20th century, different vaccines based on the vaccinia poxvirus were developed and used for vaccination against smallpox. After the eradication of smallpox, these vaccines were no longer used. Current vaccines against monkeypox virus are classified by the WHO as replicative (ACAM2000), minimally replicative (LC16m8) and non-replicative (MVA-BN), the latter being the one currently used. The 2022 extra-African monkeypox virus epidemic has highlighted the lack of vaccines with proven efficacy and low reactogenicity. It is considered that the use of this vaccine in the current outbreak may play a role in the prevention or attenuation of the disease as pre-exposure prophylaxis in close contacts of confirmed cases.
Topics: Animals; Humans; Mpox (monkeypox); Smallpox; Vaccinia virus; Monkeypox virus; Vaccination
PubMed: 36775782
DOI: 10.1016/j.medcli.2023.01.001 -
Current Opinion in Virology Oct 2022Poxviruses are large double-stranded DNA viruses that encode their own DNA replication, transcription, and mRNA biogenesis machinery, which underlies their ability to... (Review)
Review
Poxviruses are large double-stranded DNA viruses that encode their own DNA replication, transcription, and mRNA biogenesis machinery, which underlies their ability to replicate entirely in the cytoplasm. However, like all other viruses, poxviruses remain dependent on host ribosomes to translate their mRNAs into the viral proteins needed to complete their replication cycle. While earlier studies established a fundamental understanding of how poxviruses wrestle with their hosts for control of translation initiation and elongation factors that guide ribosome recruitment and mRNA decoding, recent work has begun to reveal the extent to which poxviruses directly target the ribosome itself. This review summarizes our current understanding of the regulation of ribosomes and translation in poxvirus infection.
Topics: Humans; Vaccinia virus; Ribosomes; Poxviridae; Poxviridae Infections; RNA, Messenger; Virus Replication
PubMed: 36270183
DOI: 10.1016/j.coviro.2022.101256 -
BMJ (Clinical Research Ed.) May 2022
Topics: Disease Outbreaks; Humans; Mpox (monkeypox)
PubMed: 35613732
DOI: 10.1136/bmj.o1321