CD19 and BAFF-R can signal to promote B-cell survival in the absence of Syk

28.01.2015

Hobeika E, Levit-Zerdoun E, Anastasopoulou V, Pohlmeyer R, Altmeier S, Alsadeq A, Dobenecker MW, Pelanda R, Reth M

EMBO J. 2015;34(7):925-39.

EMBO J         online article

To learn more about the role of Syk for the activation and maintenance of mature B cells the BIOSS researchers generated mice with an inducible and B cell-specific deletion of the Syk gene. Their study showed that Syk is absolutely required for the activation but, interestingly, not for the maintenance of mature B cells. Indeed, one third of the mature B cell pool survives for an extended time in the periphery without Syk. The authors also demonstrated that the survival of Syk-negative B cells requires the expression of the BCR-coreceptor CD19 and the binding of the pro survival factor BAFF to the BAFF-receptor. These findings show that B cell survival signals can be processed in the absence of a functional BCR signaling module. This helps to understand how B cells are normally maintained and how the disregulation of B cell signaling can lead to lymphomas,and autoimmunity.