Galectin-4 (Gal-4) is a β-galactoside-binding protein belonging to the galectin family. Although Gal-4 is known to be involved in several physiologic processes of the gastrointestinal tract, its immunomodulatory roles remain unclear. In this study, we investigated whether Gal-4 influences the function of M1 and M2 macrophages. Gal-4 treatment drove more robust changes in the gene expression of M2 macrophages compared to M1 macrophages. Antiviral immune response-related genes were significantly upregulated in Gal-4-treated M2 macrophages. Gal-4 significantly enhanced the immunostimulatory activity of M2 macrophages upon Toll-like receptor 7 stimulation or infection with lymphocytic choriomeningitis virus (LCMV). Moreover, the antibody production against LCMV infection and the antiviral CD4+ T-cell responses, but not the antiviral CD8+ T-cell responses, were greatly increased by Gal-4-treated M2 macrophages in vivo. The present results indicate that Gal-4 enhances the ability of M2 macrophages to promote antiviral CD4+ T-cell responses. Thus, Gal-4 could be used to boost antiviral immune responses.
Bibliographical noteFunding Information:
This research was supported by the National Research Foundation of Korea (NRF) grant funded by the Korean government (No. 2021R1I1A1A01041639 and NRF-2021R1C1C1012962) and the Chung-Ang University Graduate Research Scholarship in 2020. We acknowledge the NIH Tetramer Core Facility for providing LCMV GP33, NP396, and GP66 tetramers.
© 2023 The Author(s).
- CD4T cell
- M1 macrophage
- M2 macrophage
- lymphocytic choriomeningitis virus