Influenza Virus-Specific Neutralizing IgM Antibodies Persist for a Lifetime

• Type of Material: Article
• Authors: Ioanna Skountzou, Emory University; Lakshmipriyadarshini Satyabhama, Emory University; Anastasia Stavropoulou, University of Athens; Zuhha Ashraf, Emory University; E.Stein Esser, Emory University; Elena Vassilieva, Emory University; Dimitrios G. Koutsonanos, Emory University; Richard Compans, Emory University; Joshy Jacob, Emory University
• Language: English
• Date: 2014-11-01
• Publisher: American Society for Microbiology
• Publication Version: Final Published Version
• Copyright Statement: © 2014, American Society for Microbiology
• License: Creative Commons Attribution 3.0 Unported
• Final Published Version (URL): http://dx.doi.org/10.1128/CVI.00374-14
• Title of Journal or Parent Work: Clinical and Vaccine Immunology
• ISSN: 1556-6811
• Volume: 21
• Issue: 11
• Start Page: 1481
• End Page: 1489
• Grant/Funding Information: This work was supported by contract HHSN266 200700006C from the NIH/NIAID.
• Research Categories: Biology, General; Biology, Virology; Health Sciences, Immunology

Abstract

Detection of immunoglobulin M (IgM) antibodies has long been used as an important diagnostic tool for identifying active viral infections, but their relevance in later stages has not been clearly defined in vivo. In this study, we followed the kinetics, longevity, and function of influenza virus-specific IgM antibodies for 2 years following sublethal infection of mice with live mouseadapted A/PR/8/34 virus or immunization with formalin-inactivated virus. These groups mounted robust protective immune responses and survived lethal challenges with 50 × 50% lethal dose (LD50) mouse-adapted A/PR/8/34 virus 600 days after the primary exposure. Surprisingly, the virus-specific IgM antibodies persisted along with IgG antibodies, and we found a significantly higher number of IgM-positive (IgM+) virus-specific plasma cells than IgG+plasma cells that persisted for at least 9 months postexposure. The IgM antibodies were functional as they neutralized influenza virus in the presence of complement just as well as IgG antibodies did.