Specialties: Hematopathology

Zeta-associated protein-70 (ZAP-70) is a member of the Syk family of tyrosine kinases, a group of proteins that attach to the zeta chain components of T-cell receptors to signal downstream events involved in the regulation of cell function, proliferation, and death.¹  Research suggests that the ZAP-70 protein may also play an important role in natural killer (NK) cell activation and early B-cell development; however, it is not expressed in most normal mature B-cells.¹ Expression of ZAP-70 has been reported in various lymphomas, including mantle cell lymphoma, small lymphocytic lymphoma and marginal zone lymphoma.^{1, 2}