Involvement In Virus Infection Research Articles

Role of lymphatic endothelium specific hyaluronan receptor 1 in virus infection and associated diseases.

Lymphatic vessel endothelial hyaluronan receptor 1 (LYVE-1) serves as a prominent marker for lymphatic endothelial cells (LECs) and is pivotal in the process of lymphangiogenesis, a critical factor in cancer development and metastasis. Overexpression of LYVE-1 has been observed in various cancers, where it is recognized as an adverse prognostic indicator. Targeting LYVE-1 has demonstrated inhibitory effects on tumor cell proliferation, migration, and the formation of lymph node metastases both in vitro and in vivo. While extensive research has focused on the role of LYVE-1 in cancer cells, its involvement in virus infection and associated diseases remains largely unexplored. This review consolidates recent findings regarding the expression of LYVE-1 and its functions in lymphangiogenesis during various viral infections and the development of related diseases, with a particular emphasis on Kaposi's sarcoma herpesvirus. Despite the limited available data, it is evident that further studies are essential to comprehensively understand the contribution of LYVE-1 to viral pathogenesis and oncogenesis.

Downregulation of miR-143/145 Cluster in Breast Carcinoma Specimens: Putative Role of DNA Oncoviruses

Background: The DNA oncoviruses, including human papillomavirus (HPV) and Epstein-Barr virus (EBV) are among the most important infectious agents involved in breast carcinogenesis. These oncoviruses have a broad disrupting effect on cellular miRNAs and their functions, by which they contribute to carcinogenesis. Objectives: In this investigation, we evaluated the correlation between HPV and EBV and the expression level of tumor suppressor miRNAs (miR-143 and 145), clinical outcomes, and their association with stimulating inflammatory cytokines in patients with breast carcinoma. Methods: In our case-control study, 35 cancerous tissues and 35 adjacent non-cancerous tissues were collected from 35 patients. Nested-PCR was set up for the detection of HPV and EBV genomes, and RT-qPCR was used for miRNA expression in the case and control groups. In addition, serum specimens were obtained from all patients (n = 35) and healthy controls (n = 35) to determine the IL-8 serum concentration. Results: We found HPV and EBV in 14.2% (10/70) and 7% (5/70) of all samples, respectively. The distributions of positive samples in the case and control groups were 25.7% (9/35) and 2.9% (1/35) (P = 0.006) for HPV and 11.4% (4/35) and 2.9% (1/35) (P = 0.164) for EBV, respectively. Besides, RT-qPCR showed that miR-143 and miR-145 were significantly downregulated in HPV and EBV-infected cases compared to non-infected ones (P < 0.05). Data also indicated that the promotion of metastasis status was related to miR-143/145 downregulation and HPV infection (P = 0.003). No significant difference was found in serum IL-8 concentration concerning viral infections. Conclusions: Our results suggested the possible involvement of viral infections in breast carcinogenesis and adverse clinical outcomes by downregulating miR-143/145.

Viruses in multiple sclerosis pathogenesis

Multiple sclerosis (MS) is an extremely debilitating auto-immune disease of people characterised by demyelination of the central nervous system and progressive neurological dysfunction. The etiology of the disease is complex (including factors such as genetics, sex hormones and vitamin D levels). The involvement of viral infections as a risk factor in triggering disease has long been suspected and two classes of viruses in particular, the herpesvirus Epstein-Barr virus (EBV) and the Human endogenous retrovirus “W” family (HERV-W) have been the focus of much recent research. Despite near ubiquitious infection (EBV), or integration into the genome as a repetitive element no longer able to function as a virus (HERV-W) a picture is gradually emerging of how these are involved in MS pathogenesis. In the case of EBV, having had infectious mononucleosis (clinical disease in patients infected post-puberty) increases the risk of developing MS. For HERV-W our recent work has confirmed that RNA is over-expressed in MS patients compared with healthy controls (though basal levels vary with ethnic background) and that EBV infection of B cells triggers expression of HERV-W RNA and proteins. There is a growing body of evidence that expression of HERV-W can trigger innate immune system inflammatory responses. There is also increasing evidence for molecular mimicry between epitopes of the HERV-W env protein, the EBV EBNA1 protein and peptides from brain proteins implicated in MS pathogenesis. Crucially these peptides are also able to bind the HLA-DR2b locus that is the strongest genetic risk factor for MS development.

Mechanisms of lymphatic system-specific viral replication and its potential role in autoimmune disease.

Viral infections can be fatal because of the direct cytopathic effects of the virus or the induction of a strong, uncontrolled inflammatory response. Virus and host intrinsic characteristics strongly modulate the outcome of viral infections. Recently we determined the circumstances under which enhanced replication of virus within the lymphoid tissue is beneficial for the outcome of a disease. This enforced viral replication promotes anti-viral immune activation and, counterintuitively, accelerates virus control. In this review we summarize the mechanisms that contribute to enforced viral replication. Antigen-presenting cells and CD169+ macrophages exhibit enforced viral replication after infection with the model viruses lymphocytic choriomeningitis virus (LCMV) and vesicular stomatitis virus (VSV). Ubiquitin-specific peptidase 18 (Usp18), an endogenous type I interferon blocker in CD169+ macrophages, has been identified as a proviral gene, as are B cell activating factor (BAFF) and carcinoembryonic antigen-related cell adhesion molecule 1 (CEACAM1). Lymphotoxins (LT) strongly enhance viral replication in the spleen and lymph nodes. All these factors modulate splenic architecture and thereby promote the development of CD169+ macrophages. Tumor necrosis factor alpha (TNF-α) and nuclear factor kappa-light-chain-enhancer of activated B cell signaling (NF-κB) have been found to promote the survival of infected CD169+ macrophages, thereby similarly promoting enforced viral replication. Association of autoimmune disease with infections is evident from (1) autoimmune phenomena described during a chronic virus infection; (2) onset of autoimmune disease simultaneous to viral infections; and (3) experimental evidence. Involvement of virus infection during onset of type I diabetes is strongly evident. Epstein-Bar virus (EBV) infection was discussed to be involved in the pathogenesis of systemic lupus erythematosus. In conclusion, several mechanisms promote viral replication in secondary lymphatic organs. Identifying such factors in humans is a challenge for future studies.

Genetic characterization of a new astrovirus in goslings suffering from gout.

Since early 2016, the Chinese goose industry has experienced severe outbreaks of gout; however, the etiological factor of the disease is still unclear. Here, we investigated the possible involvement of viral infection in the disease. Using sequence-independent PCR amplification, astrovirus sequences were generated from a gout case. Full-length genomic sequencing and sequence analysis of three goose astrovirus (GoAstV) strains revealed that they belong to a new avastrovirus most closely related to viruses classified within species Avastrovirus 3. The GoAstV was detected in 16/16 gout cases collected from two provinces, supporting a pathogenic role for the new avastrovirus.

Previously diagnosed influenza infections and the risk of developing epilepsy.

Several epidemiological studies suggest a possible involvement of viral infection in the development of epilepsy. While recent research from in vitro studies increasingly supports the role of herpes simplex virus type 1 (HSV-1) in the pathogenesis of epilepsy, little is known about the role of other viral infections such as influenza. Using data from the Clinical Practice Research Datalink (CPRD), we conducted a matched case-control analysis to assess the association between GP-diagnosed influenza infections and the risk of developing an incident diagnosis of epilepsy. During the study period 11 244 incident epilepsy cases and 44 976 matched control patients were identified. Prior exposure to influenza was reported in 7·5% of epilepsy cases and 6·7% of controls [adjusted odds ratio (aOR) 1·12, 95% confidence interval (CI) 1·03-1·22]. Prior history of 'complicated influenza', i.e. influenza associated with a possible super-infection, was associated with a slightly increased epilepsy risk (aOR 1·64, 95% CI 1·10-2·46), particularly if recorded within the 2 months preceding the epilepsy diagnosis (aOR 6·03, 95% CI 1·10-33·2). Our findings suggest that prior influenza exposure does not appear to materially alter the risk of developing epilepsy. By contrast, influenza episodes accompanied by complications were associated with a slightly increased epilepsy risk.

Development of fulminant Type 1 diabetes with thrombocytopenia after influenza vaccination: a case report

Fulminant Type 1 diabetes was originally reported as idiopathic Type 1 diabetes. Involvement of viral infections in the pathogenesis of fulminant T1D has been suggested, but the development of fulminant Type 1 diabetes after influenza vaccination has not been reported. We report a case of fulminant Type 1 diabetes with thrombocytopenia following influenza vaccination. A 54-year-old man was admitted to hospital with hyperglycaemia and diabetic ketosis. Seven days before admission, he received a seasonal influenza vaccine for the prevention of influenza infection. On admission, blood glucose was 29 mmol/L and HbA1c 40 mmol/mol (5.9%). Fasting and 2-h C-peptide immunoreactivity were <0.0333 nmol/L and 0.0999 nmol/L, respectively. Anti-GAD and anti-IA-2 antibodies were negative, so no autoimmunity seemed to participate in the etiology. ELISPOT assay also showed no association with T cell-mediated autoimmunity. HLA genotypes were consistent with susceptibility to fulminant Type 1 diabetes. After the abrupt onset of diabetes, he showed mild thrombocytopenia, which has been observed for approximately 5 years after diabetes development. This is the first description of fulminant Type 1 diabetes after influenza vaccination. Our observation raises the possibility that influenza vaccination might trigger this condition via the TLR7 pathway.

A Case of Fulminant Type 1 Diabetes Associated With Significant Elevation of Mumps Titers

Type 1 diabetes mellitus is classified as either autoimmune or idiopathic. Fulminant type 1 diabetes was originally reported as a subtype of idiopathic type 1 diabetes. Though involvement of viral infections has been suggested as a triggering mechanism, its pathogenesis remains unknown. Here, we present a case of fulminant type 1 diabetes associated with significant elevation of mumps titers. A 56-year-old Japanese man had suffered from nausea and generalized fatigue for two days before being transferred to our hospital in a confused state. Findings on admission revealed a high blood glucose level, near-normal HbA1c level, metabolic acidosis, and increased urinary ketone levels. Serum tests for islet-associated autoantibodies were negative. The serum, urinary C-peptide levels and the result of glucagon test indicated severe impairment of insulin secretion. These results were compatible with the diagnosis of fulminant type 1 diabetes. Also, he was suspected as having mumps infection on the basis of serological testing. These findings suggest that fulminant type 1 diabetes developed after mumps virus infection in our case. To the best of our knowledge, no other report has indicated an association between a recent mumps infection and the onset of fulminant type 1 diabetes. This case suggests an association between fulminant type 1 diabetes and mumps virus infection.

Human membrane protein Tim-3 facilitates hepatitis A virus entry into target cells

In this study, a cellular surface membrane protein of immunoglobulin (Ig) superfamily (IgSF) was identified from a human dendritic cell (DC) cDNA library by large-scale random sequencing, which is identical to previously reported Tim-3 (T-cell Ig- and mucin-domain-containing molecule 3). Recent data have suggested the association of the 281-residue mouse Tim-3 molecule with Th1-related T cell responses and disease in mice. Human Tim-3 is a 301-residue type I membrane protein whose extracellular region contains a Cys-rich Ig-like domain and a mucin domain, the characteristics of Tim proteins. It shows significant homology to human hepatitis A virus (HAV) cellular receptor-1 (HuHAVcr-1)/Tim-1. Human Tim-3 mRNA was highly expressed in monocytes or monocyte-derived cells, and the expression level decreased when DC underwent maturation and activation. There is no previous report on the biological functions of human Tim-3, especially the involvement in virus infection. We demonstrated that HeLa cells, which are refractory to HAV infection, acquired a limited susceptibility to HAV infection after stably overexpressing human Tim-3 as confirmed by Western blot analysis using anti-Tim-3 antibody, but Tim-3-Fc fusion protein had no direct HAV-binding activity. The results indicated that human Tim-3 can promote HAV entry into target cells but itself may not function as a cellular receptor of HAV.

A Case of Fulminant Type 1 Diabetes Associated With Painless Thyroiditis

Type 1 diabetes is classified as type 1A and type 1B diabetes, which are considered to be caused by autoimmune and nonautoimmune (idiopathic) mechanisms, respectively (1). Fulminant type 1 diabetes is characterized by a rapid-onset diabetic ketoacidosis within a short period of time, normal to near-normal HbA1c level at onset, and complete β-cell destruction and was originally reported as a subtype of type 1B diabetes (2). Recently, the involvement of viral infections has been suggested to be the triggering mechanism of fulminant type 1 diabetes (3,4). The involvement of T-cell autoimmunity in this disease, however, has also been reported (5–8). Thus, its etiology is still unclear. Here, we report a case of fulminant type 1 …

Viruses and telomerase

The involvement of viral infections in the genesis of cancers is currently established. However, the narrow correlation between viruses and the activation of telomerase was defined only recently. The telomerase activity is detected in more than 85 % of human cancers and would take part to immortalization processes, associated with cellular transformation. The active minimal complex of telomerase is composed of a RNA subunit comprising a template sequence which is reverse-transcribed onto telomeres by a proteic component TERT. A disregulation of telomerase activity was observed consecutively to infection by viruses from various families. This phenomenon would mainly rest on modulation of the expression and the nuclear targeting of TERT by viral proteins or further to viral genome integrations close to the TERT gene. Moreover, the Marek's Disease herpesvirus, responsible of T-lymphomas in chickens, is particular in that it encodes, within its genome, a viral telomerase RNA subunit, vTR, which induces a more greater telomerase activity than its avian cellular counterpart, cTR.

Post-encephalitic parkinsonism: clinical features and experimental model

Post-encephalitic parkinsonism has been well documented by now. Recently, an Indian group reported some post-encephalitic parkinsonism patients that resembled Japanese encephalitis cases with bilateral substantia nigra lesions that were detected by MRI. Post-encephalitis parkinsonism has been described following Coxsackie B virus, influenza A, poliovirus and measles virus infections. The possible involvement of virus infection has also been supported by experimental animal models. We have demonstrated pathological and to a certain extent clinical features consistent with Parkinson's disease following infection of rats with Japanese encephalitis virus (JEV). We evaluated new treatments with Parkinson's disease using this model. It was reported that tremor primarily involving the fingers, tongue and eyelids, muscle rigidity and masked face as the clinical features by JEV. Recently brainstem lesions produced by West Nile virus, which is a flavivirus like JEV, were documented by MRI. In the future, post-encephalitic parkinsonism may be found elsewhere in the world. In adult Fischer rats sacrificed 12 weeks after infection with JEV at the age of 13 days, neuronal loss with gliosis was confined mainly to the zona compacta of the bilateral substantia nigra, without lesions in the cerebral cortex and cerebellum. Furthermore, the most severe lesions were in the central part of zona compacta; the lateral cell groups were less affected. Thus, the distribution of the pathologic lesions in infected rats resembled those found in Parkinson's disease. JEV-infected rats showed marked bradykinesia. Significant behavioral improvement was observed upon administration of L-DOPA and monoamine oxidase (MAO) inhibitor. The findings suggest that JEV infection of rats under the conditions described may serve as a model of virus induced Parkinson's disease.