What are the steps for the activation of proliferation and differentiation of B cells?

1. two or more Ig molecules need to cross-link together by the binding of two or more antigens 2. the signals that arise are transduced by receptor-associated proteins 3. the tyrosines of ITAM are phosphorylated by kinases 4. Syk tyrosine kinase is recruited and phosphorylates tyrosine residues on adapter proteins 5. the adaptor proteins recruit and activate many molecules 6. the result is proliferation and differentiation of B cells