Homing Receptor Statement in Mucosal B Cell Development

To determine the temporal sequence in which rotavirus specific B cells appear in intestinal Peyer's patches (PP), mesenteric lymph nodes (MLN), spleen, bone marrow (BM), and intestinal lamina propria (LP); to define the B cells' developmental stage through analyses of their cell surface phenotype and/or expression of cytoplasmic or secreted Ig, and the isotype of antibody produced; to determine their expression of specific homing receptors involved in trafficking to intestinal sites and to characterize their responses to chemotactic cytokines. <P>These studies should define critical developmental transitions in homing properties and provide a framework for considering the alterations in B cell phenotype (and associated shifts in the localization of antigen-specific populations) during development of the humoral immune response. They also constitute the first direct assessment of the regulation of chemokine/chemoattractant responses on lymphocytes participating in a physiologic immune response. Definition of unique chemoattractant responses characteristic of intestinal vs. peripheral immunization, or of defined stages in the intestinal B cell response to antigen, could lead to novel approaches to the therapeutic modulation of tissue-specific immune responses in vivo.