B Cell-Intrinsic Expression of Interferon Regulatory Factor 1 Supports Chronic Murine Gammaherpesvirus 68 Infection. J Virol 2020 Jun 16;94(13)
Date
04/24/2020Pubmed ID
32321819Pubmed Central ID
PMC7307145DOI
10.1128/JVI.00399-20Scopus ID
2-s2.0-85086682413 (requires institutional sign-in at Scopus site) 8 CitationsAbstract
Gammaherpesviruses are ubiquitous pathogens that are associated with cancers, including B cell lymphomas. These viruses are unique in that they infect naive B cells and subsequently drive a robust polyclonal germinal center response in order to amplify the latent reservoir and to establish lifelong infection in memory B cells. The gammaherpesvirus-driven germinal center response in combination with robust infection of germinal center B cells is thought to precipitate lymphomagenesis. Importantly, host and viral factors that selectively affect the gammaherpesvirus-driven germinal center response remain poorly understood. Global deficiency of antiviral tumor-suppressive interferon regulatory factor 1 (IRF-1) selectively promotes the murine gammaherpesvirus 68 (MHV68)-driven germinal center response and expansion of the viral latent reservoir. To determine the extent to which antiviral effects of IRF-1 are B cell intrinsic, we generated mice with conditional IRF-1 deficiency. Surprisingly, B cell-specific IRF-1 deficiency attenuated the establishment of chronic infection and the germinal center response, indicating that MHV68 may, in a B cell-intrinsic manner, usurp IRF-1 to promote the germinal center response and expansion of the latent reservoir. Further, we found that B cell-specific IRF-1 deficiency led to reduced levels of active tyrosine phosphatase SHP1, which plays a B cell-intrinsic proviral function during MHV68 infection. Finally, results of this study indicate that the antiviral functions of IRF-1 unveiled in MHV68-infected mice with global IRF-1 deficiency are mediated via IRF-1 expression by non-B cell populations.IMPORTANCE Gammaherpesviruses establish lifelong infection in over 95% of all adults and are associated with B cell lymphomas. The virus's manipulation of the germinal center response and B cell differentiation to establish lifelong infection is thought to also precipitate malignant transformation, through a mechanism that remains poorly understood. The host transcription factor IRF-1, a well-established tumor suppressor, selectively attenuates MHV68-driven germinal center response, a phenotype that we originally hypothesized to occur in a B cell-intrinsic manner. In contrast, in testing, B cell-intrinsic IRF-1 expression promoted the MHV68-driven germinal center response and the establishment of chronic infection. Our report highlights the underappreciated multifaceted role of IRF-1 in MHV68 infection and pathogenesis.
Author List
Jondle CN, Johnson KE, Uitenbroek AA, Sylvester PA, Nguyen C, Cui W, Tarakanova VLAuthor
Vera Tarakanova PhD Professor in the Microbiology and Immunology department at Medical College of WisconsinMESH terms used to index this publication - Major topics in bold
AnimalsB-Lymphocytes
Female
Gammaherpesvirinae
Germinal Center
Herpesviridae Infections
Host-Pathogen Interactions
Interferon Regulatory Factor-1
Lymphocyte Activation
Male
Mice
Mice, Inbred C57BL
Spleen
Virus Latency