Vaccines (Basel) 2020 Nov 9;8(4). Epub 2020 Nov 9.
Department of Microbiology, Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place, Box 1124, New York, NY 10029, USA.
PLoS One 2021 7;16(1):e0245244. Epub 2021 Jan 7.
Department of Pathology, National Institute of Infectious Diseases, Shinjuku, Tokyo, Japan.
IgA antibodies, which are secreted onto the mucosal surface as secretory IgA antibodies (SIgAs), play an important role in preventing influenza virus infection. A recent study reported that anti-hemagglutinin (HA) head-targeting antibodies increase anti-viral functions such as hemagglutination inhibition (HI) and virus neutralization (NT), in addition to HA binding activity (reactivity) via IgA polymerization. However, the functional properties of anti-viral IgA antibodies with mechanisms of action distinct from those of anti-HA head-targeting antibodies remain elusive. Read More
The stalk domain of the hemagglutinin has been identified as a target for induction of protective antibody responses due to its high degree of conservation among numerous influenza subtypes and strains. However, current assays to measure stalk-based immunity are not standardized. Hence, harmonization of assay readouts would help to compare experiments conducted in different laboratories and increase confidence in results. Read More
Vaccine 2020 01 7;38(4):852-858. Epub 2019 Nov 7.
Department of Microbiology and Immunology, Faculty of Tropical Medicine, Mahidol University, Thailand. Electronic address:
Background: The emergence and spread of highly pathogenic avian influenza (H5N1) viruses have raised global concerns of a possible human pandemic, spurring efforts towards H5N1 influenza vaccine development and improvements in vaccine administration methods. We previously showed that a prime-boost vaccination strategy induces robust and broadly cross-reactive antibody responses against the hemagglutinin globular head domain. Here, we specifically measure antibodies against the conserved hemagglutinin stem region in serum samples obtained from the prior study to determine whether stalk-reactive antibodies can also be induced by the prime-boost regimen. Read More
J Virol 2019 11 15;93(21). Epub 2019 Oct 15.
Department of Medicine, Section of Rheumatology, The University of Chicago, Chicago, Illinois, USA
Vaccination is the best measure of protection against influenza virus infection. Vaccine-induced antibody responses target mainly the hemagglutinin (HA) surface glycoprotein, composed of the head and the stalk domains. Recently two novel vaccine platforms have been developed for seasonal influenza vaccination: a recombinant HA vaccine produced in insect cells (Flublok) and Flucelvax, prepared from virions produced in mammalian cells. Read More
J Virol 2019 04 3;93(8). Epub 2019 Apr 3.
David H. Smith Center for Vaccine Biology and Immunology, Department of Microbiology and Immunology, University of Rochester Medical Center, Rochester, New York, USA
Memory B cells (MBCs) are key determinants of the B cell response to influenza virus infection and vaccination, but the effect of different forms of influenza antigen exposure on MBC populations has received little attention. We analyzed peripheral blood mononuclear cells and plasma collected following human H3N2 influenza infection to investigate the relationship between hemagglutinin-specific antibody production and changes in the size and character of hemagglutinin-reactive MBC populations. Infection produced increased concentrations of plasma IgG reactive to the H3 head of the infecting virus, to the conserved stalk, and to a broad chronological range of H3s consistent with original antigenic sin responses. Read More