title: Recruitment and retention of B cells in the central nervous system in response to alphavirus encephalomyelitis.
abstract: Sindbis virus (SINV) infection of neurons results in nonfatal viral encephalomyelitis and provides a model system for understanding recovery from virus infection of the central nervous system (CNS). Infection is followed by clearance of infectious virus, a gradual decrease in viral RNA, and then long-term maintenance of low levels of viral RNA. Antibody to the E2 glycoprotein is important for virus clearance, and B cells enter the CNS along with CD4(+) and CD8(+) T cells during the early clearance phase. Antibody-secreting cells (ASCs) are present in the CNS and become enriched for SINV-specific ASCs. We have evaluated the factors within the CNS that facilitate continued local antibody production after infection. Expression of CXCL9, CXCL10, CCL1, CCL2, and CCL5 chemokine mRNAs increased early, and infiltrating B cells expressed CXCR3, CXCR5, and CCR7. The mRNAs for IL-10 and IL-21, cytokines important for B cell proliferation and differentiation, rose rapidly and remained elevated long after clearance of infectious virus. Active proliferation of B cells, as indicated by Ki-67 expression, continued for months. Bromodeoxyuridine (BrdU) labeling of proliferating cells showed that ASCs produced in the draining cervical lymph nodes during the early germinal center response were preferentially retained in the CNS. Sustained increase in B-cell-activating factor (BAFF) mRNA in the CNS and BAFF receptor expression by B cells coincided with the long-term maintenance of SINV-specific ASCs in the brain. We conclude that multiple changes in the brain microenvironment facilitate B-cell entry and support proliferation and differentiation and long-term survival of antiviral ASCs during recovery from alphaviral encephalomyelitis.
authors.affiliation: W. Harry Feinstone Department of Molecular Microbiology and Immunology, Johns Hopkins University Bloomberg School of Public Health, Baltimore, Maryland, USA.
authors.forename: Talibah U
authors.initials: TU
authors.lastname: Metcalf
authors.forename: Victoria K
authors.initials: VK
authors.lastname: Baxter
authors.forename: Voraphoj
authors.initials: V
authors.lastname: Nilaratanakul
authors.forename: Diane E
authors.initials: DE
authors.lastname: Griffin
mesh_terms: D018354:Alphavirus Infections / Q000276:immunology* / Q000821:virology; D000818:Animals; D000921:Antibody-Producing Cells / Q000276:immunology; D053265:B-Cell Activation Factor Receptor / Q000096:biosynthesis / Q000378:metabolism; D001402:B-Lymphocytes / Q000276:immunology* / Q000821:virology; D001921:Brain / Q000276:immunology* / Q000821:virology; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology; D002454:Cell Differentiation; D049109:Cell Proliferation; D018925:Chemokines / Q000096:biosynthesis / Q000235:genetics; D004679:Encephalomyelitis / Q000276:immunology* / Q000821:virology; D005260:Female; D016753:Interleukin-10 / Q000235:genetics; D007378:Interleukins / Q000235:genetics; D019394:Ki-67 Antigen / Q000096:biosynthesis; D008198:Lymph Nodes / Q000276:immunology; D051379:Mice; D008810:Mice, Inbred C57BL; D051757:PAX5 Transcription Factor / Q000235:genetics; D012333:RNA, Messenger / Q000096:biosynthesis; D012367:RNA, Viral / Q000378:metabolism; D012845:Sindbis Virus / Q000276:immunology*; D013116:Spinal Cord / Q000276:immunology / Q000821:virology; D014759:Viral Envelope Proteins / Q000276:immunology; D000098546:Interleukin-21
chemical_list: D053265:B-Cell Activation Factor Receptor; D018925:Chemokines; D007378:Interleukins; D019394:Ki-67 Antigen; D051757:PAX5 Transcription Factor; D012333:RNA, Messenger; D012367:RNA, Viral; D014759:Viral Envelope Proteins; C064950:glycoprotein E2, Sindbis virus; D016753:Interleukin-10; D000098546:Interleukin-21