The origin of the plasma cell heterogeneity

Plasma cells are terminally differentiated B-cells producing large amount of Ig. In humans, most of circulating Ig is produced by bone marrow plasma cells. Plasma cells (PCs) differentiate from activated naïve or memory B-cells usually activated by specific antigens during an infection. It is still controversial whether the regulation of the PC number and the “active” in vivo Ig diversity depend or not on non-specific reactivation of B-cells during infections. Depending on the stimuli and the types of B-cells (naïve or memory, circulating or germinal center, lymph nods or spleen, B1 or B2…), both the phenotype and isotype of PCs are different suggesting that the PC diversity is either linked to B-cell diversity or to the type of stimulus (TI, TD…) or to both. The knowledge of the mechanisms supporting PC diversity has important consequences for human health for the management of i) plasma cell neoplasia such as Multiple Myeloma, Waldenstrom’s Macroglobulinemia, ii) vaccine protection against pathogens and iii) auto-immune diseases.

The following topics could be addressed as original articles, reviews or opinions
- the cytokines/growth factors sustaining survival of plasmablasts and PCs
- the molecular pathways of differentiation and survival
- the different types of PCs, phenotype and location
- the different types of B-cells able to differentiate into PCs
- the “Darwinian” regulation of the PC generation
- the microenvironment role in PC survival
- the abnormal plasma cells