FIGURE 4.

Endolysosomal tubules do not require the proper trafficking of class II MHC molecules. BMDCs derived from mice expressing class II MHC-eGFP but lacking an invariant chain (Ii^−/−) were transduced to express CD63-mRFP1. A, In the absence of LPS, CD63 was found in its normal vesicular compartment whereas class II MHC was found in a reticular pattern suggestive of ER retention. B, After LPS stimulation, the CD63 compartment formed endolysosomal tubules, but no class II MHC tubules were seen in the endolysosomal tubules. Scale bars represent 5 µm.