09-17-2007, 09:31 PM
i checked kaplan generation of humoral effector mechanism it says :B-cells need two signals for fully differentiatio into antibodysecreting cell and memory cell : 1st after leaving the bone marrow it enter follicular area of lymph node and spleen where it cross -link with Ag ....the 2nd signal is congugation with TH ie MHC class2 and the release of its cytokines..