Expression profiling of B-1 and B-2 progenitors (36.15)

Abstract

B-1 and B-2 comprise the two B cell lineages. B-1 and B-2 cells can be distinguished by their surface phenotype and also by their developmental ontology, immunoglobulin repertoire, anatomical localization, and immune functions. Importantly, B-1 cells arise early in fetal liver while B-2 cells are generated in the bone marrow after birth. The appearance of B-1 and B-2 cells is the result of fetal B-cell development versus adult B-cell development. B-1 and B-2 cells are generated from distinct progenitor cells, namely B-1 progenitors and B-2 progenitors. B-1 progenitors express CD19 but do not express B220. In contrast, B-2 progenitors express B220 but do not express CD19. To determine the fate decisions that led to fetal versus adult B cell development, we sorted B-1 progenitor cells from fetal liver and B-2 progenitor cells from adult bone marrow and performed gene expression array analysis. In our poster, we will present the results of the expression array comparison between the two progenitor populations. We will confirm the expression array comparison results by molecular techniques and discuss the potential significance of these differences.