Raft-dependent endocytic movement and intracellular cluster formation during T  cell activation triggered by concanavalin A

Publication date: Available online 12 July 2017 Source:Journal of Bioscience and Bioengineering Author(s): Satomi Yabuuchi, Satoshi Endo, KeangOk Baek, Kunihide Hoshino, Yoshio Tsujino, Mun'delanji C. Vestergaard, Masahiro Takagi Certain food ingredients can stimulate the human immune system. A lectin, concanavalin A (ConA), from Canavalia ensiformis (jack bean) is one of the most well-known food-derived immunostimulants and mediates activation of cell-mediated immunity through T cell proliferation. Generally, T cell activation is known to be triggered by the interaction between T cells and antigen-presenting cells (APCs) via a juxtacrine (contact-dependent) signaling pathway. The mechanism has been well characterized and is referred to as formation of the immunological synapse (IS). We were interested in the mechanism behind the T cell activation by food-derived ConA which might be different from that of T cell activation by APCs. The purpose of this study was to characterize T cell activation by ConA with regard to (i) movement of raft domain, (ii) endocytic vesicular transport, (iii) the cytoskeleton (actin and microtubules), and (iv) cholesterol composition. We found that raft-dependent endocytic movement was important for T cell activation by ConA and this movement was dependent on actin, microtubules, and cholesterol. The T cell signaling mechanism triggered by ConA can be defined as endocrine signaling which is distinct from the activation process triggered by...
Source: Journal of Bioscience and Bioengineering - Category: Biomedical Science Source Type: research