The CPB2 gene product was discovered independently byvarious groups in the early to mid-1990s and as a resulthas been assigned different names by each laboratory. In1989, Hendriks et al. [1,2] described a labile enzyme thatinterfered with their assay for carboxypeptidase N. A yearlater, he and co-workers assigned this enzyme the namecarboxypeptidase U, with ‘U’ symbolizing unstable, afundamental property of the enzyme . Within a fewyears, the CPB2 gene product (this term is used through-out to avoid bias) came to be referred to by many othernames, including plasma carboxypeptidase B  and car-boxypeptidase R . The regulatory role of the CPB2gene product in ﬁbrinolysis was not fully appreciateduntil 1995, when Bajzar, Manuel and Nesheim describedthe puriﬁcation and characterization of a carboxypepti-dase zymogen that was activated by thrombin . Theytermed this novel ﬁbrinolytic inhibitor ‘thrombin activat-able ﬁbrinolysis inhibitor’ (TAFI), another widely usedsynonym for the CPB2 gene product. More recently,additional roles of the CPB2 gene product have beendescribed, including its ability to regulate inﬂammation.As a result, additional names such as thrombin-activata-ble carboxypeptidase B  and carboxypeptidase B2 have been assigned to the CPB2 gene product, furthercomplicating the literature. The lack of uniformity of theCPB2 gene product nomenclature has raised issues con-cerning literature searches and prompted the Scientiﬁcand Standardization Committee (SSC) on ﬁbrinolysis toassess whether the ﬁbrinolysis community is willing toharmonize the CPB2 gene product nomenclature.
- CBP2 gene product
- carboxypeptidase B2