Dynamics of Virus-Specific Memory B Cells and Plasmablasts following Viral Infection of the Central Nervous System
Authors: Cornelia C Bergmann
Jeffrey R Atkinson
Mihyun Hwang
Angel Reyes-Rodriguez
Journal: Journal of Virology (2019)
Discipline: MICROBIOLOGY
Keywords: B cell responses; central nervous system infections; coronavirus; germinal centers; neuroimmunology
Affiliations: Department of Neurosciences, Lerner Research Institute, Cleveland Clinic Foundation, Cleveland, Ohio, USA., School of Biomedical Sciences, Kent State University, Kent, Ohio, USA., Department of Neurosciences, Lerner Research Institute, Cleveland Clinic Foundation, Cleveland, Ohio, USA .

Abstract:  Humoral responses within the central nervous system (CNS) are common to many neurotropic viral infections, with antibody (Ab)-secreting cells (ASC) contributing to local protection. However, a role for virus-specific memory B cells (Bmem) within the CNS is poorly explored due to lack of robust phenotypic or functional identification in mice. This study takes advantage of the progeny of mice expressing tamoxifen-inducible Cre recombinase (Cre-ERT2) under the Aicda promoter crossed with Rosa26-loxP-tdTomato reporter mice (AIDCre-Rosa26tdTomato) to monitor B cells having undergone activation-induced cytidine deaminase (AID)-mediated somatic hypermutation (SHM) following neurotropic coronavirus infection. AID detection via tdTomato expression allowed tracking of virus-specific ASC and Bmem in priming and effector sites throughout infection. In draining lymph nodes, tdTomato-positive (tdTomato+) ASC were most prevalent prior to germinal center (GC) formation, but total tdTomato+ B cells only peaked with robust GC formation at day 14 p.i. Moreover, their proportion of Bmem dominated over the proportion of ASC throughout infection. In the CNS, tdTomato+ cells started emerging at day 14 p.i. While they initially comprised mainly Bmem, the proportions of ASC and Bmem became similar as tdTomato+ B cells increased throughout viral persistence. Delayed tamoxifen treatment demonstrated ongoing CNS recruitment of tdTomato+ B cells, mainly ASC, primed late during GC reactions. Overall, the data support the idea that virus-induced B cells exhibiting SHM require peripheral GC formation to emerge in the CNS. Ongoing GC reactions and regional signals further regulate dynamics within the CNS, with preferential maintenance of tdTomato+ B cells in spinal cords relative to that in brains during viral persistence.IMPORTANCE The prevalence and role of antigen-specific Bmem in the CNS during viral encephalomyelitis is largely undefined. A lack of reliable markers identifying murine Bmem has made it difficult to assess their contribution to local antiviral protection via antigen presentation or conversion to ASC. Using reporter mice infected with neurotropic coronavirus to track virus-specific Bmem and ASC, this report demonstrates that both subsets only emerge in the CNS following peripheral GC formation and subsequently prevail. While early GC reactions supported preferential Bmem accumulation in the CNS, late GC reactions favored ASC accumulation, although Bmem outnumbered ASC in draining lymph nodes throughout infection. Importantly, virus-specific B cells undergoing sustained GC selection were continually recruited to the persistently infected CNS. Elucidating the factors governing temporal events within GCs, as well as regional CNS cues during viral persistence, will aid intervention to modulate CNS humoral responses in the context of infection and associated autoimmune pathologies. 

Retracted: No

PubPeer comments:
 Fig 1A.  Coronary artery changes the relative expression of miR-383-3p, ILIR2, and caspase-1 in the myocardial tissues of the normal and AS rats. A, Oil red O staining results reveal that mature atherosclerotic plaques are observed in the coronary artery of AS rats . ![file] The Normal artery appears to be the same as in Fig. 1 of [Huang et al (2017)] .  Microscope images of the coronary artery . ![file] No authors in common. , 
 Fig 3B.  Up-regulated miR-383-3p decreases the mRNA and protein expression of IL1R2 and caspase-1 by RT-qPCR; (A) RT-qPCR reveals that miR-383-3p expression is notably increased, while the mRNA expression of IL1R2 and caspase-1 evidently decreases after treated by miR-383-3p mimic; (B) IL1R2 and caspase-1 show weaker protein band in the protein band plot after treated by miR-383-3p mimic . ![file] The loading-control band has appeared in a range of papers from different authors. The bubbles under one blob and providing an eye for another make them distinctive. , 
 Retracted [30 June 2021] . ---------------------------------------- The above article, published online on 25 April 2018 in Wiley Online Library has been retracted by agreement between the journal s Editor in Chief, Prof. Dr. Christian Behl, and Wiley Periodicals LLC. The retraction has been agreed following an investigation based on allegations raised by a third party. A detailed investigation revealed that several image elements of the experimental data were published elsewhere in a different scientific context. Thus, the editors consider the conclusions of this article to be invalid. ,