Functional Characterization of Ly49 + CD8 T-Cells in Both Normal Condition and During Anti-Viral Response

• Published in: Frontiers in immunology 2021-01, Vol.11, p.602783-602783
• Main Authors: Shytikov, Dmytro, Rohila, Deepak, Li, Dan, Wang, Pengfei, Jiang, Mei, Zhang, Mingxu, Xu, Qin, Lu, Linrong
• Format: Article
• Language: English
• Subjects: Adoptive Transfer; Animals; anti-viral response; CD8 T-cells; CD8-Positive T-Lymphocytes - immunology; CD8-Positive T-Lymphocytes - metabolism; CD8-Positive T-Lymphocytes - transplantation; CD8-Positive T-Lymphocytes - virology; Cell Proliferation; Chlorocebus aethiops; Cytokines - metabolism; Disease Models, Animal; Host-Pathogen Interactions; Immunologic Memory; Immunology; Ly49 receptors; Lymphocyte Activation; Lymphocytic Choriomeningitis - genetics; Lymphocytic Choriomeningitis - immunology; Lymphocytic Choriomeningitis - metabolism; Lymphocytic Choriomeningitis - virology; Lymphocytic choriomeningitis virus - immunology; Lymphocytic choriomeningitis virus - pathogenicity; memory phenotype; Mice; Mice, Inbred C57BL; Mice, Knockout; NK Cell Lectin-Like Receptor Subfamily A - genetics; NK Cell Lectin-Like Receptor Subfamily A - metabolism; NK-cell receptors; Phenotype; Signal Transduction; Vero Cells
• ISSN: 1664-3224; 1664-3224
• DOI: 10.3389/fimmu.2020.602783

The role of Ly49 CD8 T-cells in the immune system is not clear. Previously, several papers suggested Ly49 CD8 T-cells as immunosuppressors, while multiple studies also suggested their role as potent participants of the immune response. The mechanism of Ly49 expression on CD8 T-cells is also not clear. We investigated phenotype, functions, and regulation of Ly49 expression on murine CD8 T-cells in both normal state and during LCMV infection. CD8 T-cells express different Ly49 receptors compared with NK-cells. In intact mice, Ly49 CD8 T-cells have a phenotype similar to resting central memory CD8 T-cells and do not show impaired proliferation and cytokine production. Conventional CD8 T-cells upregulate Ly49 receptors during TCR-induced stimulation, and IL-2, as well as IL-15, affect it. At the same time, Ly49 CD8 T-cells change the Ly49 expression profile dramatically upon re-stimulation downregulating inhibitory and upregulating activating Ly49 receptors. We observed the expression of Ly49 receptors on the virus-specific CD8 T-cells during LCMV infection, especially marked in the early stages, and participation of Ly49 CD8 T-cells in the anti-viral response. Thus, CD8 T-cells acquire Ly49 receptors during the T-cell activation and show dynamic regulation of Ly49 receptors during stimulation.