Figure 2.

Human PLTs express TLR9 in distinct granules along the periphery of the cell, adjacent to the plasma membrane. (A and B) Washed human whole-blood PLTs were spun down onto poly-l-lysine–coated glass cover slides, permeabilized with 0.5% Triton X-100 for 5 min, and were probed for either TLR9 alone or TLR9 and β1-tubulin together. (A) Samples were examined by wide-field fluorescence microscopy and revealed peripheral labeling of TLR9 in distinct, punctate granules that localized mostly (69 ± 5%) along the cell periphery, adjacent to the plasma membrane. (B) TLR9 localization to the cell edge was confirmed in human PLTs by colabeling with β1-tubulin to demarcate the PLT border. Inset represents magnified region outlined by the yellow box. (inset) Bar, 5 µm.