T cell receptor sharing by cytotoxic T lymphocytes facilitates efficient virus control

• Published in: Proceedings of the National Academy of Sciences - PNAS Vol. 106; no. 35; pp. 14984 - 14989
• Main Authors: Chaudhri, Geeta, Quah, Ben J, Wang, Yang, Tan, Abel H.Y, Zhou, Jie, Karupiah, Gunasegaran, Parish, Christopher R
• Format: Journal Article
• Language: English
• Published: United States National Academy of Sciences 01.09.2009; National Acad Sciences
• Subjects: Animals; Antigens; Antiviral activity; Biological Sciences; CD8 antigen; Cell Membrane - immunology; Cells, Cultured; Cloning; Coculture Techniques; Cytotoxicity; Data processing; DNA-Binding Proteins - deficiency; DNA-Binding Proteins - metabolism; Ectromelia virus - immunology; Ectromelia, Infectious - blood; Ectromelia, Infectious - immunology; Effector cells; Epitopes - immunology; Female; Immune system; Infection; Lymphocytes; Lymphocytes B; Lymphocytes T; Membranes; Mice; Mice, Inbred C57BL; Mice, Knockout; Receptors, Antigen, T-Cell - immunology; T cell receptors; T-cell receptor; T-Lymphocytes, Cytotoxic - immunology; Viral Load; Viruses
• ISSN: 0027-8424; 1091-6490
• DOI: 10.1073/pnas.0906554106

A remarkable feature of the adaptive immune system is the speed at which small numbers of antigen-specific lymphocytes can mediate a successful immune response. Rapid expansion of T and B lymphocyte clones that have receptors specific for a particular antigen is one of the primary means by which a swift response is generated. Although much of this clonal expansion is caused by the division of antigen-specific cells, here we demonstrate an additional mechanism by which the pool of effector T cells against a viral infection can quickly enlarge. Our data show that virus-specific CD8⁺ cytotoxic T lymphocytes (CTL) can transfer their T cell receptors (TCR) to recipient CTL of an unrelated specificity that, as a consequence, gain the antigen specificity of the donor T cell. This process occurs within minutes via membrane exchange and results in the recipient CTL acquiring the ability to recognize and eliminate cells targeted by the donor TCR, while still retaining the antigen specificity of its own TCR. Such receptor sharing allows rapid, proliferation-independent expansion of virus-specific T cell clones of low frequency and plays a highly significant antiviral role that can protect the host from an otherwise lethal infection.