New insights to the functional role of the T cell-Antigen Presenting Cell immunological synapse

• Main Authors: MUSTAPHA FAROUDI, ROSSANA ZARU, BENOIT FAVIER, SALVATORE VALITUTTI
• Format: Article
• Language: English
• Published: BMC 2002-01-01
• Series: Biological Research
• Subjects: T cell antigen receptor; Immunological synapse; signal transduction
• Online Access: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-97602002000200004

Three innovative and complementary morphological approaches were employed to study the T cell/antigen presenting cell (APC) interaction: (i) high resolution three-dimensional confocal microscopy of the T cell-APC contact site; (ii) time lapse video recording in living T cells of [Ca2+]I and changes in distribution of various GFP fusion proteins with TCR/CD3-zetacomplex associated- and other signaling components; (iii) measurement of lateral TCR mobility and that of recruited signaling components using techniques based on fluorescence recovery after photo-bleaching. These approaches were combined with biochemical and functional experiments to investigate two principal issues: (A) Recruitment and the three-dimensional arrangement of receptors and signaling components at the contact site between human CD4+ T lymphocytes and APCs, (B) Structure of the immunological synapse formed at the contact site between cytotoxic T lymphocytes (CTLs) and target cells. We discuss evidence indicating that TCR engagement and triggering can occur in the absence of large-scale molecular segregation into the T cell-APC contact site. Taken together our results indicate that although not required for TCR engagement and triggering, formation of the IS is important to reinforce TCR-mediated signal transduction and achieve full T cell activation.