T cell responses are governed by avidity and co-stimulatory thresholds.

Journal article

We analyzed the avidity and CD28-mediated co-stimulatory requirements for the activation of T cells in vivo and in vitro. The strength of the T cell/antigen-presenting cell interaction was varied by using altered peptide ligands for stimulation. Co-stimulatory requirements were studied using T cells from CD28-deficient mice. The results indicate that T cell activation is not an all-or-nothing event, but occurs in distinct steps. For each step, a certain avidity, co-stimulatory threshold or both, must be met. Depending upon the strength of the interaction between the T cell receptor and the major histocompatibility complex/peptide and the presence of CD28 co-stimulatory signals, T cells may undergo blast formation alone or proliferate or eventually both proliferate and differentiate to effector cells. Thus, T cell activation is governed by both avidity and co-stimulatory thresholds.

Authors: Bachmann, M; Sebzda, E; Kündig, T; Shahinian, A; Speiser, D

• Publication status: Published
• Journal: European journal of immunology
• Volume: 26
• Issue: 9
• Pages: 2017-2022
• Publication date: 1996-09-01
• DOI: 10.1002/eji.1830260908
• EISSN: 1521-4141
• ISSN: 0014-2980
• Language: English
• Keywords: Amino Acid Sequence; Lymphocyte Activation; Receptors, Antigen, T-Cell; Molecular Sequence Data; Lymphocytic choriomeningitis virus; Animals; Mice, Transgenic; Antigens, CD28; Peptide Fragments; Histocompatibility Antigens; Mice; Cytotoxicity, Immunologic; Interleukin-2; Cytokines; T-Lymphocytes