Frontline: Optimal T cell activation requires the engagement of CD6 and CD166

Journal article

The T cell surface glycoprotein, CD6 binds CD166 in the first example of an interaction between a scavenger receptor cysteine-rich domain and an immunoglobulin-like domain. We report that in human these proteins interact with a KD =0.4-1.0 μM and Koff ≥0.4-0.63 s-1, typical of many leukocyte membrane protein interactions. CD166 also interacts in a homophilic manner but with around 100-fold lower affinity (KD =29-48 μM and Koff ≥ 5.3 s-1). At concentrations, that will block the CD6/CD166 interaction, soluble monomeric CD6 and CD166 inhibit antigen-specific human T cell responses. This is consistent with extracellular engagement between CD6 and CD166 being required for an optimal immune response. © 2004 Wiley-VCH Verlag GmbH and Co. KGaA.

Authors: Hassan, N; Barclay, N; Brown, M

• Journal: European Journal of Immunology
• Volume: 34
• Issue: 4
• Pages: 930-940
• Publication date: 2004-04-01
• DOI: 10.1002/eji.200424856
• ISSN: 0014-2980
• Language: English
• Keywords: CD6; Affinity; T cell activation; CD166