A New Humanized Mouse Model of Epstein‐Barr Virus Infection That Reproduces Persistent Infection, Lymphoproliferative Disorder, and Cell‐Mediated and Humoral Immune Responses

Abstract

The functional human immune system, including T, B, and natural killer lymphocytes, is reconstituted in NOD/Shi-scid/IL-2Rgamma(null) (NOG) mice that receive hematopoietic stem cell transplants. Here, we show that these humanized mice can recapitulate key aspects of Epstein-Barr virus (EBV) infection in humans. Inoculation with approximately 1 x 10(3) TD(50) (50% transforming dose) of EBV caused B cell lymphoproliferative disorder, with histopathological findings and latent EBV gene expression remarkably similar to that in immunocompromised patients. Inoculation with a low dose of virus (<or=1 x 10(1) TD(50)), in contrast, resulted in apparently asymptomatic persistent infection. Levels of activated CD8(+) T cells increased dramatically in the peripheral blood of infected mice, and enzyme-linked immunospot assay and flow cytometry demonstrated an EBV-specific T cell response. Immunoglobulin M antibody specific to the EBV-encoded protein BFRF3 was detected in serum from infected mice. The NOG mouse is the most comprehensive small-animal model of EBV infection described to date and should facilitate studies of the pathogenesis, prevention, and treatment of EBV infection.

Intrathecal immune responses to EBV in early MS

“…Considering that antigen-specific CD8 1 T cells infiltrate and persist in the brain if their cognate antigen is present [33], and considering that the CD8 1 T-cell response is proportional to the EBV viral load [34], we could hypothesize that there is an intrathecal EBV reactivation in the CSF of early MS patients. Such a reactivation has been reported by Serafini et al, who detected an increased EBV reactivation in post-mortem brain tissue of two acute MS cases [18].…”

A Cluster of Virus-Encoded MicroRNAs Accelerates Acute Systemic Epstein-Barr Virus Infection but Does Not Significantly Enhance Virus-Induced Oncogenesis In Vivo

“…Humanized mice generated by transplanting CD34 ϩ hematopoietic stems cells into immune-deficient mice devoid of mouse lymphoid cells are systemically reconstituted with human myeloid and lymphoid cells, including human B cells (the primary target cell of EBV) (17). EBV infection of humanized mice recapitulates several key aspects of human infection, including a virus-specific CD8 ϩ T cell immune response and the development of latency III EBV-associated tumors (18)(19)(20). To understand the in vivo contribution of the BHRF1 miRNA cluster to EBV infection and EBV-induced tumorigenesis, we monitored EBV infection and assessed tumor formation in humanized mice exposed to wild-type (WT) virus, a viral mutant (⌬123) that lacks all three BHRF1 miRNAs, and a revertant (REV) virus that was created by reexchanging the original BHRF1 miRNA sequences back into the ⌬123 mutant (11).…”

Animal models of Epstein Barr virus infection

“…Depending on the dose of EBV, it is possible to generate asymptomatic persistent infection or acute infectious mononucleosis-like symptoms, as well as lymphoproliferative disease in HIS mice (Yajima et al, 2008). Latency III expressing cells can be found in all of these instances, as assessed by immunohistochemistry and in situ hybridization for EBV-encoded RNAs (EBERs), EBNA1, EBNA2, and LMP1 (Cocco et al, 2008;Strowig et al, 2009).…”

“…The development of certain EBV-associated diseases can be studied in HIS mice. Infection with a high dose of EBV wild-type strain B95-8 leads to lymphoproliferative disease and tumor generation (Yajima et al, 2008;Strowig et al, 2009). B cells primarily harbor the virus and can be purified from EBV-infected HIS mice and cultured in vitro as immortalized lymphoblastoid cell lines (LCLs).…”

“…Animal with HLA transgenes allow for the thymic selection of T cells on these molecules and result in similar epitope specificities as in patients. Regardless of the source, these T cells produce IFN-γ in response to cognate CD8 + T cell epitopes (Strowig et al, 2009) and autologous LCLs (Traggiai et al, 2004;Melkus et al, 2006;Yajima et al, 2008). Moreover, both CD4 + and CD8 + T cell clones that were primed during EBV infection of HIS mice are able to lyse LCLs (Strowig et al, 2009) …”