Multiple DNA Viruses and HPV Integration in Inverted Papilloma and Associated Sinonasal Carcinoma.

OBJECTIVES: Sinonasal inverted papilloma (IP) has a locally destructive growth pattern, can relapse, and can undergo malignant transformation (IP-associated sinonasal squamous cell carcinoma (IP-SNSCC)). Human papillomaviruses (HPV)-6 and -16 are frequently detected in IPs. To clarify the possible roles of other DNA viruses in IPs, we explored viruses not studied in this context before. With the setting of pre- and post-malignant transformation samples, we investigated HPV genomes in depth to assess the integration of HPV into the human genome and the presence of minor intratypic variants. MATERIALS AND METHODS: We analyzed 35 IP samples representing 28 individuals, of which six had IP-SNSCC. For virus screening, we applied qPCR to detect 16 different DNA viruses in three virus families, comprising herpesviruses, parvoviruses, and polyomaviruses. In addition, targeted next generation sequencing (NGS) was used for detailed HPV analysis. RESULTS: We detected herpes-, parvo-, and polyomaviruses in 13/28 (46%) patients, with codetections of multiple viruses in six (21%) patients. NGS revealed HPV16 DNA in 2/6 IP-SNSCC and in their respective earlier benign IP samples, as well as in a plasma sample from one of these patients. HPV6 was detected in two IP samples without subsequent malignant transformation. We identified sequence reads containing junctions of HPV6 and HPV16 and host genome suggestive of viral integration. HPV6 and HPV16 minor intratypic variants were present across pre- and post-malignant transformation, with mostly nonsynonymous mutations. CONCLUSIONS: Multiple DNA viruses were present in IPs. HPV16 was detected only in IP-SNSCCs or in tumors that later underwent malignant transformation. LEVEL OF EVIDENCE: 3 Laryngoscope, 2024.

Structural Characterization of Human Bufavirus 1: Receptor Binding and Endosomal pH-Induced Changes.

Bufaviruses (BuV) are members of the Parvoviridae of the Protoparvovirus genus. They are non-enveloped, T = 1 icosahedral ssDNA viruses isolated from patients exhibiting acute diarrhea. The lack of treatment options and a limited understanding of their disease mechanisms require studying these viruses on a molecular and structural level. In the present study, we utilize glycan arrays and cell binding assays to demonstrate that BuV1 capsid binds terminal sialic acid (SIA) glycans. Furthermore, using cryo-electron microscopy (cryo-EM), SIA is shown to bind on the 2/5-fold wall of the capsid surface. Interestingly, the capsid residues stabilizing SIA binding are conserved in all human BuVs identified to date. Additionally, biophysical assays illustrate BuV1 capsid stabilization during endo-lysosomal (pH 7.4-pH 4) trafficking and capsid destabilization at pH 3 and less, which correspond to the pH of the stomach. Hence, we determined the cryo-EM structures of BuV1 capsids at pH 7.4, 4.0, and 2.6 to 2.8 Å, 3.2 Å, and 2.7 Å, respectively. These structures reveal capsid structural rearrangements during endo-lysosomal escape and provide a potential mechanism for this process. The structural insights gained from this study will add to the general knowledge of human pathogenic parvoviruses. Furthermore, the identification of the conserved SIA receptor binding site among BuVs provides a possible targetable surface-accessible pocket for the design of small molecules to be developed as anti-virals for these viruses.

Presence of herpesviruses, parvoviruses, and polyomaviruses in sinonasal lymphoma.

PURPOSE: Sinonasal lymphoma (SL) is a rare lymphatic neoplasm of the nasal cavities, paranasal sinuses and nasopharynx. Whereas some risk factors for SL subtypes have been identified, their aetiology is unknown. Along with other predisposing factors, the viral association of lymphomas, such as Epstein-Barr virus (EBV) and Burkitt and Hodgkin lymphomas, is well-established. Modern molecular biology techniques have enabled the discovery of novel human viruses, exemplified by the protoparvovirus cutavirus (CuV), associated with cutaneous T-cell lymphoma. These findings, and the anatomical location of the sinonasal tract with its rich microbiome and infectious agents, justify in-depth studies among SL. METHODS: We analysed the presence of 20 viruses of Orthoherpesviridae, Parvoviridae, and Polyomaviridae by qPCR in 24 SL tumours. We performed RNAscope in situ hybridisation (RISH) to localize the viruses. Parvovirus-specific IgG was analysed by enzyme immunoassay and targeted next-generation sequencing (NGS) was applied to detect CuV in plasma. RESULTS: We detected viral DNA in 15/24 (63%) tumours; nine of EBV, six of human herpesvirus (HHV) -7, four each of HHV-6B and parvovirus B19, two of cytomegalovirus, and one each of CuV and Merkel-cell polyomavirus. We found tumours with up to four viruses per tumour, and localized CuV and EBV DNAs by RISH. Two of the ten plasma samples exhibited CuV IgG, and one plasma sample demonstrated CuV viremia by NGS. CONCLUSION: Viruses were frequent findings in SL. The EBV detection rate was high in diffuse large B-cell lymphoma, and co-detections with other viruses were prevalent.

Viral DNA in submandibular gland tissue with an inflammatory disorder.

Background: The etiology behind different types of chronic sialadenitis (CS), some of which exhibit IgG4 overexpression, is unknown. Further, IgG4-related disease (IgG4-RD) commonly affects the submandibular gland, but its relationship to IgG4-overexpressing CS, and the antigen triggering IgG4 overexpression, remain unknown. Materials and Methods: By qPCR, we assessed the presence of 21 DNA-viruses causing IgG4 overexpression in submandibular gland tissue from patients with IgG4-positive and IgG4-negative CS. Healthy submandibular glands and glands with sialolithiasis without CS were used as controls. We examined the distribution of HHV-7, HHV-6B and B19V DNA, within virus PCR-positive tissues with RNAscope in-situ hybridization (RISH). Results: We detected DNA from seven viruses in 48/61 samples. EBV DNA was more prevalent within the IgG4-positive samples (6/29; 21%) than the IgG4-negative ones (1/19; 5.3%). B19V DNA was more prevalent within the IgG4-negative samples (5/19; 26%) than the IgG4-positive ones (4/29; 14%). The differences in virus prevalence were not statistically significant. Of the IgG4-RD samples (n = 3) one contained HHV-6B DNA. RISH only showed signals of HHV-7. Conclusions: None of the studied viruses are implicated as triggering IgG4-overexpression in CS. Although our results do not confirm viral etiology in the examined conditions, they provide valuable information on the prevalence of viruses in both diseased and healthy submandibular gland tissue.

WSV2023 - The second meeting of the world society for virology: One health - One world - One virology.

The Second International Conference of the World Society for Virology (WSV), hosted by Riga Stradins University, was held in Riga, Latvia, on June 15-17th, 2023. It prominently highlighted the recent advancements in different disciplines of virology. The conference had fourteen keynote speakers covering diverse topics, including emerging virus pseudotypes, Zika virus vaccine development, herpesvirus capsid mobility, parvovirus invasion strategies, influenza in animals and birds, West Nile virus and Marburg virus ecology, as well as the latest update in animal vaccines. Discussions further explored SARS-CoV-2 RNA replicons as vaccine candidates, SARS-CoV-2 in humans and animals, and the significance of plant viruses in the 'One Health' paradigm. The presence of the presidents from three virology societies, namely the American, Indian, and Korean Societies for Virology, highlighted the event's significance. Additionally, past president of the American Society for Virology (ASV), formally declared the partnership between ASV and WSV during the conference.

Prevalence, tropism, and activity of cutavirus in circulating blood lymphocytes, stool, and skin biopsy specimens of patients with cutaneous T-cell lymphoma and parapsoriasis en plaques.

A significant association has been established between a newly emerging human parvovirus, cutavirus (CuV), and cutaneous T-cell lymphoma/mycosis fungoides (CTCL/MF) and its precursor parapsoriasis en plaques (PP). CTCL is a heterogeneous group of skin malignancies of T cells, the cause of which remains unknown. This study aimed to determine the activity, spread, and cell tropism of the skin-persistent CuV. CuV DNA was detected in both skin biopsies (6/20, 30%) and peripheral blood mononuclear cells (PBMCs) (4/29, 13.8%) from 49 CTCL/MF or PP patients, while none from 33 patients with any other type of skin disease or healthy subjects harbored CuV DNA. CuV DNA persisted in the skin or PBMCs for up to 15 years, despite circulating CuV-specific IgG. Spliced CuV mRNA was expressed in skin, indicating viral activity. Also, both of two available stool samples contained encapsidated CuV genomes, suggesting that the patients excrete infectious virus into the environment. Finally, CuV was observed to target circulating and skin-resident CD4 + T cells and some skin keratinocytes and macrophages. This is especially intriguing as malignant T cells in CTCL develop from CD4 + T cells. Hence, CuV should be further investigated for the overall role it plays in the complex tumor microenvironment of CTCL/MF.

Human bocavirus 1 coinfection is associated with decreased cytokine expression in the rhinovirus-induced first wheezing episode in children.

BACKGROUND: Rhinovirus (RV)-induced first wheezing episodes in children are associated with a markedly increased risk of asthma. Previous studies have suggested that human bocavirus 1 (HBoV1) may modify RV-induced immune responses in young children. We investigated cytokine profiles of sole RV- and dual RV-HBoV1-induced first wheezing episodes, and their association with severity and prognosis. METHODS: Fifty-two children infected with only RV and nine children infected with dual RV-HBoV1, aged 3-23 months, with severe first wheezing episodes were recruited. At acute illness and 2 weeks later, peripheral blood mononuclear cells were isolated, and stimulated with anti-CD3/anti-CD28 in vitro. Multiplex ELISA was used to quantitatively identify 56 different cytokines at both study points. Patients were prospectively followed for 4 years. RESULTS: The mean age of the children was 14.3 months, and 30% were sensitized. During the acute illness, the adjusted analyses revealed a decrease in the expression of IL-1b, MIP-1b, Regulated upon activation, normal T cell expressed and presumably secreted (CCL5), TNF-a, TARC, and ENA-78 in the RV-HBoV1 group compared with the RV group. In the convalescence phase, the RV-HBoV1 group was characterized by decreased expression of Fractalkine, MCP-3, and IL-8 compared to the RV group. Furthermore, the hospitalization time was associated with the virus group and cytokine response (interaction p < 0.05), signifying that increased levels of epidermal growth factor and MIP-1b were related with a shorter duration of hospitalization in the RV-HBoV1 coinfection group but not in the RV group. CONCLUSIONS: Different cytokine response profiles were detected between the RV and the RV-HBoV1 groups. Our results show the idea that RV-induced immune responses may be suppressed by HBoV1.

Significant Association of Cutavirus With Parapsoriasis en Plaques: High Prevalence Both in Skin Swab and Biopsy Samples.

Cutavirus (CuV) is associated with cutaneous T-cell lymphoma (CTCL), of which parapsoriasis is a precursor. Our study reveals a significantly higher CuV-DNA prevalence in skin swabs of parapsoriasis patients (6/13; 46.2%) versus those of healthy adults (1/51; 1.96%). Eight patients (8/12; 66.7%) had CuV DNA in biopsied skin, and 4 developed CTCL.

Herpesviruses, polyomaviruses, parvoviruses, papillomaviruses, and anelloviruses in vestibular schwannoma.

Etiology of vestibular schwannoma (VS) is unknown. Viruses can infect and reside in neural tissues for decades, and new viruses with unknown tumorigenic potential have been discovered. The presence of herpesvirus, polyomavirus, parvovirus, and anellovirus DNA was analyzed by quantitative PCR in 46 formalin-fixed paraffin-embedded VS samples. Five samples were analyzed by targeted next-generation sequencing. Viral DNA was detected altogether in 24/46 (52%) tumor samples, mostly representing anelloviruses (46%). Our findings show frequent persistence of anelloviruses, considered normal virome, in VS. None of the other viruses showed an extensive presence, thereby suggesting insignificant role in VS.