Immunosuppressive FK506 treatment leads to more frequent EBV-associated lymphoproliferative disease in humanized mice

Abstract

Post-transplant lymphoproliferative disorder (PTLD) is a potentially fatal complication after organ transplantation frequently associated with the Epstein-Barr virus (EBV). Immunosuppressive treatment is thought to allow the expansion of EBV-infected B cells, which often express all eight oncogenic EBV latent proteins. Here, we assessed whether HLA-A2 transgenic humanized NSG mice treated with the immunosuppressant FK506 could be used to model EBV-PTLD. We found that FK506 treatment of EBV-infected mice led to an elevated viral burden, more frequent tumor formation and diminished EBV-induced T cell responses, indicative of reduced EBV-specific immune control. EBV latency III and lymphoproliferationassociated cellular transcripts were up-regulated in B cells from immunosuppressed animals, akin to the viral and host gene expression pattern found in EBV-PTLD. Utilizing an unbiased gene expression profiling approach, we identified genes differentially expressed in B cells of EBV-infected animals with and without FK506 treatment. Upon investigating the most promising candidates, we validated sCD30 as a marker of uncontrolled EBV proliferation in both humanized mice and in pediatric patients with EBV-PTLD. High levels of sCD30 have been previously associated with EBV-PTLD in patients. As such, we believe that humanized mice can indeed model aspects of EBV-PTLD development and may prove useful for the safety assessment of immunomodulatory therapies.

EBV renders B cells susceptible to HIV-1 in humanized mice

“…Although direct interactions between HIV-1 and B cells have been reported several decades ago (22,23), there are, to our knowledge, no reports of HIV-1 replication in B cells in vivo or experimental coinfection of HIV-1 with EBV in vivo, as reviewed in reference 24. In this study, we aimed to characterize the influence of EBV infection on HIV-1 susceptibility and possible HIV-1 integration in EBV-transformed B cells for lentiviral reservoir generation, as well as its influence on viral and host gene transcription in comparison to CD4 + T cells in vitro. Humanized mice have been successfully used to separately investigate HIV-1 and EBV infection, pathogenesis, and immune control, and we and others could recapitulate the protective value of CD4 + or CD8 + T cells against EBV-mediated lymphoproliferation in these models (25,26,27,28). Here, we modelled and investigated the effect of HIV-1 on EBV-specific immune control via coinfection of humanized mice.…”

Probing Reconstituted Human Immune Systems in Mice With Oncogenic γ-Herpesvirus Infections

“…In addition, however, low levels of latency I and II with EBNA1 as the sole or in addition LMP1 and 2 protein expression could be detected (18,23). Low levels of these lower latencies were also verified by detection of characteristic viral transcripts (21,24,25). While latency III is found in naïve B cells of healthy EBV carriers, latency II predominates in germinal center B cells and latency I in homeostatically replicating memory B cells (26,27).…”

“…In most of these studies a high dose of infectious viral particles from the B95-8 EBV strain, originally isolated during symptomatic primary infection called infectious mononucleosis (IM), was used. As in secondary lymphoid tissues, including tonsils, of IM patients (22) primarily EBV infected B cells expressing the latency III infection program with six nuclear antigen (EBNA1, 2, 3A-C, and LP), two latent membrane proteins (LMP1,2) as well as non-translated EBER and viral miRNAs, were observed (21). In addition, however, low levels of latency I and II with EBNA1 as the sole or in addition LMP1 and 2 protein expression could be detected (18,23).…”

“…In order, however, to explore the protective capacity of the reconstituted human immune system compartments, at least some of the EBV and KSHV associated pathologies must be recapitulated in these humanized mouse systems. Accordingly, the viral gene expression patterns have been analyzed after EBV infection of humanized mice (16)(17)(18)(19)(20)(21). In most of these studies a high dose of infectious viral particles from the B95-8 EBV strain, originally isolated during symptomatic primary infection called infectious mononucleosis (IM), was used.…”

Redirecting T Cells against Epstein–Barr Virus Infection and Associated Oncogenesis

“…Protection by CD8 + and CD4 + T cells, NK cells, NKT cells and γδ T cells has been demonstrated [31][32][33][34][35][36][37][38]. In addition, the pharmacological inhibition of T cell function by FK506 (tacrolimus), that increases the risk for PTLD development in transplant patients elevates EBV loads in infected HIS mice and virus associated lymphoma incidence [39]. Moreover, antibody mediated blocking of the co-receptors 2B4 or PD-1 on T cells also compromises EBV specific immune control in HIS mice [40,41].…”