Uirusu最新文献

Since the identification of severe fever with thrombocytopenia syndrome (SFTS) and its pathogen, a tick-borne bunyavirus, SFTS virus, there has been increasing interest in emerging viral infections caused by previously unknown viruses in ticks. This study aims to develop a comprehensive detection method for tick-borne bunyaviruses, conduct genetic analysis, isolate the detected viruses, and perform biological characterization. Through these studies, novel tick-borne bunyaviruses that have caused or may cause emerging infectious diseases were discovered. Tick-borne infections often occur sporadically, making their occurrence difficult to recognize. Therefore, continuous exploration of viruses in ticks and assessment of their potential risks causing human and animal diseases is required.

Human norovirus (HuNoV) is an infectious virus that accounts for more than half of all cases of infectious gastroenteritis, but its mechanism of infection and multiplication within the host are largely unknown. Accordingly, there are no available vaccines or specific therapeutic agents　applicable to HuNoV infection. The primary reason for this is the absence of an established in vitro culture and growth system for HuNoV. Therefore, virological analysis of HuNoV has been conducted using murine norovirus, which is most closely related to HuNoV and can be cultured in some cell-lines. Recently, several laboratories have reported successful in vitro cultivation of HuNoV using human intestinal epithelial cells, raising expectations for further advancements in HuNoV research. In this paper, we present recent findings regarding the in vitro propagation system of HuNoV.  .

Cytotoxic T lymphocytes (CTLs) play an important role in the control of various viral infection. CTLs recognize a complex of HLA (human leukocyte antigen) class I molecule and epitope peptide derived from viral protein on the cell surface via T cell receptors and can destroy virally infected cells. It is becoming evident that SARS-CoV-2 specific T cells play a crucial role in the control of COVID-19. We characterized T cells specific for various SARS-CoV-2 variants and identified that a L452R mutation in the Delta spike protein evades HLA-A*24:02-restricted T cell responses and increases virus infectivity. In contrast, HLA-A*24:02-restricted T cells strongly suppresses Omicron BA.1 replication due to a G446S mutation, located just outside the N-terminus of the cognate epitope, in the Omicron BA.1 variant via enhanced antigen processing and presentation of the epitope. These data indicate that T cell specific for antigens derived from variable regions is highly susceptible for the mutation and its location. The detail analysis of antigen-specific T cell responses toward variants provides better insights for the rational design of vaccine antigens or immunotherapy to induce efficient cellular immunity against new emerging viruses/variants.

Epstein-Barr virus (EBV) is a ubiquitous human lymphotropic herpesvirus that causes several malignancies. EBV infects approximately 90% of individuals worldwide. Recent studies have provided robust evidence for a causal role of EBV in multiple sclerosis. Multiple sclerosis is the most prevalent chronic inflammatory and degenerative disease of the central nerve system (CNS) that progresses over time to progressive neurodegeneration and disability. Here, I review how a ubiquitous virus can elicit autoreactive antibodies through molecular mimicry between viral and host CNS antigens, triggering multiple sclerosis.