title: NSOM/QD-based visualization of GM1 serving as platforms for TCR/CD3 mediated T-cell activation.
abstract: Direct molecular imaging of nanoscale relationship between T-cell receptor complexes (TCR/CD3) and gangliosidosis GM1 before and after T-cell activation has not been reported. In this study, we made use of our expertise of near-field scanning optical microscopy(NSOM)/immune-labeling quantum dots- (QD-)based dual-color imaging system to visualize nanoscale profiles for distribution and organization of TCR/CD3, GM1, as well as their nanospatial relationship and their correlation with PKC θ signaling cascade during T-cell activation. Interestingly, after anti-CD3/anti-CD28 Ab co-stimulation, both TCR/CD3 and GM1 were clustered to form nanodomains; moreover, all of TCR/CD3 nanodomains were colocalized with GM1 nanodomains, indicating that the formation of GM1 nanodomains was greatly correlated with TCR/CD3 mediated signaling. Specially, while T-cells were pretreated with PKC θ signaling inhibitor rottlerin to suppress IL-2 cytokine production, no visible TCR/CD3 nanodomains appeared while a lot of GM1 nanodomains were still observed. However, while T-cells are pretreated with PKCα β signaling inhibitor GÖ6976 to suppress calcium-dependent manner, all of TCR/CD3 nanodomains were still colocalized with GM1 nanodomains. These findings possibly support the notion that the formation of GM1 nanodomains indeed serves as platforms for the recruitment of TCR/CD3 nanodomains, and TCR/CD3 nanodomains are required for PKCθ signaling cascades and T-cell activation.
authors.affiliation: Laboratory of Nanophotonic Functional Materials and Devices, South China Normal University, Guangzhou, Guangdong 510006, China.
authors.forename: Liyun
authors.initials: L
authors.lastname: Zhong
authors.forename: Zhun
authors.initials: Z
authors.lastname: Zhang
authors.forename: Xiaoxu
authors.initials: X
authors.lastname: Lu
authors.forename: Shengde
authors.initials: S
authors.lastname: Liu
authors.forename: Crystal Y
authors.initials: CY
authors.lastname: Chen
authors.forename: Zheng W
authors.initials: ZW
authors.lastname: Chen
mesh_terms: D017252:CD3 Complex / Q000378:metabolism*; D005677:G(M1) Ganglioside / Q000378:metabolism*; D006801:Humans; D007376:Interleukin-2 / Q000378:metabolism; D007527:Isoenzymes / Q000378:metabolism; D008213:Lymphocyte Activation / Q000276:immunology*; D008853:Microscopy / Q000379:methods*; D061848:Optical Imaging; D011493:Protein Kinase C / Q000378:metabolism; D000074121:Protein Kinase C-theta; D045663:Quantum Dots / Q000378:metabolism*; D011948:Receptors, Antigen, T-Cell / Q000378:metabolism*; D015398:Signal Transduction; D013601:T-Lymphocytes / Q000201:enzymology / Q000276:immunology*
chemical_list: D017252:CD3 Complex; D007376:Interleukin-2; D007527:Isoenzymes; D011948:Receptors, Antigen, T-Cell; D005677:G(M1) Ganglioside; C076233:PRKCQ protein, human; D011493:Protein Kinase C; D000074121:Protein Kinase C-theta