Immune Netw.  2019 Aug;19(4):e25. 10.4110/in.2019.19.e25.

Extrinsic Acquisition of CD80 by Antigen-Specific CD8⁺ T Cells Regulates Their Recall Immune Responses to Acute Viral Infection

• Son J
• Ha SJ

• KMID: 2455935
• DOI: http://doi.org/10.4110/in.2019.19.e25

Abstract

CD80 is mainly expressed on Ag-presenting cells (APCs) as a costimulatory molecule but is also detected on T cells. However, the origin and physiological role of CD80 on CD8⁺ T cells remain unclear. In the present study, we demonstrated that effector and memory CD8⁺ T cells, but not naïve CD8⁺ T cells, displayed CD80 molecules on their surfaces after acute lymphocytic choriomeningitis virus infection. Using adoptive transfer of CD80-knockout (KO) CD8⁺ T cells into a wild type or CD80-KO recipient, we demonstrated that the effector CD8⁺ T cells displayed CD80 by both intrinsic expression and extrinsic acquisition, while memory CD8⁺ T cells displayed CD80 only by extrinsic acquisition. Interestingly, the extrinsic acquisition of CD80 by CD8⁺ T cells was observed only in the lymphoid organs but not in the periphery, indicating the trogocytosis of CD80 molecules via interaction between CD8⁺ T cells and APCs. We compared the recall immune responses by memory CD8⁺ T cells that either extrinsically acquired CD80 or were deficient in CD80, and found that CD80, presented by memory CD8⁺ T cells, played a role in limiting their expansion and IL-2 production upon exposure to secondary challenge. Our study presents the in vivo dynamics of the extrinsic acquisition of CD80 by Ag-specific CD8⁺ T cells and its role in the regulation of recall immune responses in memory CD8+ T cells.

Keyword

B7-1 antigen; Extrinsic acquisition; Trogocytosis; Recall immune response; Lymphocytic choriomeningitis virus

MeSH Terms

Adoptive Transfer
Antigens, CD80
Interleukin-2
Lymphocytic choriomeningitis virus
Memory
T-Lymphocytes*
Antigens, CD80
Interleukin-2