Cav-1 is required for optimal clustering of Lck and the TCR upon activation. (A) Scheme of the PLA between Lck and the TCR. Proximity between Lck and CD3δ results in red fluorescent signals. (B) Purified conventional CD4⁺ T cells were either unstimulated, stimulated with 10 μg/mL anti-TCR antibody (145-2C11), or 1 mM pervanadate at 37°C for 5 minutes. PLA between the TCR (CD3δ) and Lck was performed. Representative pictures of an experiment of 3 independently performed repetitions are shown. (C) Quantification of the experiment shown in (B). Mean ± SEM was plotted (n = 3 per group). perV, pervanadate; uns, unstimulated.