Which CD marker indicates the presence of activated B cells?

The presence of CD27 is indicative of activated B cells. CD27 is a member of the tumor necrosis factor receptor superfamily and is typically expressed on the surface of activated B cells. When B cells are engaged by an antigen and receive the necessary signals for activation, they express CD27, which plays a crucial role in their differentiation, growth, and survival.

In the context of B cell activation, CD27 serves as a marker for memory B cells, marking their development and indicating that these cells have undergone prior activation and clonal expansion in response to an antigen. This is important for understanding the adaptive immune response since memory B cells are essential for quicker and more robust responses upon re-exposure to the same antigen.

While other markers may be involved in B cell development and activation, they are not as definitive for indicating activated B cells. CD23, for example, is a marker associated with follicular B cells and may be expressed at different stages of B cell maturation. CD40 is involved in T-B cell interactions and is important for activation but does not serve as a specific marker for activated B cells. CD10 is associated with early B cell development and is not indicative of activation.

Understanding the significance of CD27 helps distinguish between the various stages