The topics of this volume include regulation of the helper T cell subset involved in inflammatory responses versus the subset of helper T cells involved in promoting B cells responses in humoral immunity, the regulation of T cell activity in inflammatory and autoimmune disease by the tumor necrosis factor superfamily of receptors and their ligands, the wide array of inhibitory and activating receptor that regulate natural killer cell function, phylogeny of Ig gene superfamily members linked to the major histocompatibility gene complex, the IgFc receptor family and a newly discovered family of Fc receptor homologs, the role of complement in linking innate and adaptive immunity, and manipulation of the potential for plants to protect themselves by innate and adaptive responses to viruses.