Ab16745

HeLa cells were incubated with LTM-mCherry (0.5 μM), mCherry-LTM (0.5 μM), or LTM-TPP1 (2 μM) for 2 hours. Cells were washed with ice-cold phosphate-buffered saline (PBS), fixed with 4% paraformaldehyde, and permeabilized with 0.5% Triton X-100. mCherry constructs were visualized with a rabbit polyclonal antibody against mCherry (Abcam, ab16745) and anti-rabbit Alexa Fluor 568 (Thermo Fisher Scientific). LAMP1 was stained with a mouse primary antibody (DSHB 1D4B) and anti-mouse Alexa Fluor 488 (Thermo Fisher Scientific).
Colocalization was quantified using the Volocity (PerkinElmer) software package to measure Manders’ coefficients of mCherry signal with LAMP1 signal. The minimal threshold for the 488- and 568-nm channels was adjusted to correct the background signal. The same threshold for both channels was used for all the cells examined.
CLN2^−/− fibroblast 19494 were incubated with LTM-TPP1 (2 μM) for 2 hours. Cells were washed with ice-cold PBS, fixed with 4% paraformaldehyde, and permeabilized with 0.5% Triton X-100. LTM-TPP1 was visualized with a mouse monoclonal against TPP1 (Abcam, ab54685) and anti-mouse Alexa Fluor 488 (Thermo Fisher Scientific). LAMP1 was stained with rabbit anti-LAMP1 and anti-rabbit Alexa Fluor 568 (Thermo Fisher Scientific).