Table 1.
Overview of in-house developed assays and commercially available quantification kits for the determination of different forms of the CPB2 gene product in human plasma.
| Assay Type | Interference or Influence of | Additional Information | Used in | |||||
|---|---|---|---|---|---|---|---|---|
| Thr/Ile325 | CPN | ProCPU | CPU | CPUi | ||||
| ProCPU measurement | ||||||||
| Activity * | Wang et al. 1994 [26] | No | Yes | - | Yes | No | Hip-Arg with detection by RP-HPLC | |
| Mosnier et al. 1998 [11] | No | Yes | - | Yes | No | Hip-Arg with colorimetric detection | [27,28,29] | |
| Schatteman et al. 1999 [30] | No | Yes | - | Yes | No | Hip-Arg with detection by RP-HPLC | [31,32,33] | |
| Schatteman et al. 2001 [34] | No | Yes | - | Yes | No | p-OH-Hip-Arg with colorimetric detection | [35] | |
| Heylen et al. 2010 [9] | No | No | - | Yes | No | Bz-o-cyano-Phe-Arg with detection by RP-HPLC; Not very sensitive to influence of hemolysis | [36] | |
| STA-Stachrom® TAFI (Diagnostica Stago) |
No | No | - | Yes | No | Azoformyl–AA2—AA1 (Patent: SERBIO PCT/FR 02/02376) with colorimetric detection | [37] | |
| Actichrome® TAFI (American Diagnostica) |
No | No | - | Yes | No | Chromogenic substrate with colorimetric detection; No longer marketed |
[38,39,40,41,42,43,44] | |
| Pefakit® TAFI (Pentapharm) |
No | No | - | Yes | No | Synthetic substrate with colorimetric detection | [45,46,47,48,49,50,51,52,53] | |
| ELISA | Mosnier et al. 1998 [11] | Unk. | No | - | Unk. | Unk. | Murine monoclonal capture and rabbit polyclonal detection antibody | [54,55] |
| van Tilburg et al. 2000 [56] | No | No | - | Yes | Yes | Electroimmunoassay | [56,57,58,59,60] | |
| Strömqvist et al. 2001 [13] | Unk. | No | - | No | No | No reaction with plasma of other species (guinea pig, rat, dog, pig, hamster) | ||
| Ceresa et al. 2006 [12] | No ** | No | - | No | No | Monoclonal capture and detection antibody | [58,59,61,62,63] | |
| VisuLize® TAFI (Affinity Biologicals) |
Yes | No | - | Yes | Yes | Sheep polyclonal capture and detection antibody; Marketed by Milan Analytica | [40,41,42,43,64,65,66,67,68,69,70] | |
| Imuclone® TAFI (American Diagnostica) |
Yes | No | - | No | No | [71,72,73,74,75] | ||
| Asserachrom® TAFI-1B1 (Diagnostica Stago) | No | No | - | No | No | Previously marketed by Kordia Laboratory Supplies; No longer marketed | [51,76,77,78,79,80,81,82,83,84] | |
| Zymutest® (Total) TAFI (Hyphen BioMed) |
No | No | - | No | No | Previously marketed as Zymutest® proTAFI | [38,85,86,87,88] | |
| Coalize® TAFI (Chromogenix) |
Unk. | No | - | Unk. | Unk. | Monoclonal capture and polyclonal detection antibody | [39,89] | |
| Activation peptide | ||||||||
| ELISA | Ceresa et al. 2006 [12] | No *** | No | No | Yes | No | Monoclonal capture and detection antibody; Measures both AP and CPU | [58,59,61,63] |
| Active CPU | ||||||||
| Activity | Hendriks et al. 1989 [90] | No | Yes | No | - | No | p-OH-Hip-Arg with colorimetric detection and Hip-Arg with detection by RP-HPLC | |
| Kim et al. 2008 [91] | No | No | No | - | No | Plasmin-modified fibrin is covalently bound to a quencher molecule and mixed with fluorescein-labeled plasminogen and the plasma sample. The rate of fluorescence increase detected by a plate reader reflects the amount of CPU present in the sample. High sensitive (LOD: 12 pM); Not affected by other hemostatic factors | ||
| Heylen et al. 2010 [92] | No | No | No | - | No | Bz-o-cyano-Phe-Arg with detection by RP-HPLC; High sensitive (LOD: 18 pM); Highly sensitive to influence of hemolysis | [93,94,95] | |
| ELISA | Zymutest® (Activatable) TAFI (Hyphen BioMed) | Yes | Previously marketed as Zymutest® TAFI | [53,96,97] | ||||
| Active & inactive CPU **** | ||||||||
| ELISA | Asserachrom TAFIa/ai (Diagnostica Stago) |
No | No | No | - | - | Combined measurement of CPU and CPUi; Not sensitive to influence of hemolysis | [37,63] |
| Imubind® TAFIa/ai (Biomedica Diagnostics) |
No | No | No | - | - | No longer marketed | [98] | |
This is a non-exhaustive list of methods that are available for the measurement of different forms of the CPB2 gene product. Methods used in clinical studies that are discussed in this review (or derivative methods) were included in this table. * Requires quantitative activation of proCPU prior to measurement. Consecutive measurements can reveal proCPU consumption (ongoing CPU activation). ** T12D11/T30E5. *** T12D11/T18A8. **** Reflects past or ongoing CPU generation over a longer period. AA: amino acid; AP: activation peptide; CPN: carboxypeptidase N; CPU: carboxypeptidase U (TAFIa, CPB2); CPUi: inactivated CPU; ELISA: enzyme-linked immunosorbent assay; LOD: limit of detection; proCPU: procarboxypeptidase U (TAFI, proCPB2); RP-HPLC: reversed phase high pressure liquid chromatography; TAFI: thrombin-activatable fibrinolysis inhibitor (proCPU, proCPB2); Unk.: unknown.