B cell activation can be quantitated indirectly by assaying antibody production or directly by measuring cellular changes that occur immediately after exposure to an activation signal. Provides methods for the latter (direct) approach--namely, methods for quantifying early parameters of B cell activation such as increases in intracellular ionized calcium concentration [Ca2+]I, cell size, and MHC class II-antigen expression.

Protocol: Early Events in B Lymphocyte Activation Protocol