Gene expression signatures of human plasma cells isolated from different territories. Homo sapiens

In vivo antigen (Ag)-induced differentiation of B lymphocytes into plasma cells (PCs) takes place in extra-follicular foci and germinal centers of the secondary lymphoid organs (SLOs). Most of these SLO PCs are short-living and only relatively few PCs, characterized by secreting high-affinity antibodies (Ab), travel through the circulation and finally home in specialized survival niches of the bone marrow (BM) and, at a lesser extent, in the SLOs, where they become long-living Ab-secreting PCs. We have employed whole genome microarray expression profiling as a discovery platform to identify genes with the potential to distinguish between human circulating Ag-induced PCs in comparison with tonsil and BM PCs distinctively regulate genes involved in cell proliferation. Overall design: Gene expressions in human plasma cells isolated from tonsil (7 samples), blood (6 samples) and bone marrow (7samples) were measured. Each sample was isolated from a different donor.