Step 2: In the meantime, a Dendritic Cell needs to pick up enemies at the battlefield and turn them into antigens (wieners) which are put in the MHC class II molecules (hot dog buns) and travel to the T Cell dating area in the lymph node. Here it needs to find a Helper T Cell that is able to recognize the antigen with its unique T Cell receptor (eat the wiener from the bun). If this happens the Helper T Cell is activated and makes a lot of copies of itself.
