HEMOCLOT ™ LA-S /LA-C

A new formulation dRVVT

Sensitive and Specific for Lupus Anticoagulant

Introduction

Lupus Anticoagulant (LA) is an immunoglobulin directed against negatively charged phospholipid-protein complexes, therefore yielding prolonged clotting times in phospholipid dependent coagulation assays. These antibodies are associated with different clinical states such as lupus, autoimmune disease, thrombosis and fetal loss.

Laboratory diagnosis of LA , as described in the SSC/ISTH guidelines, is based on both clotting and immunological assays.

β2-Glycoprotein I (β2-GPI) antibodies have been reported to correlate strongly with thrombotic risk and are involved in the pathogenesis of LA. β2-GPI plays a role in the response against gram negative bacteria and endotoxins (Lipopolysaccharides (LPS)). Antibodies to β2-GPI are associated with this defense reaction. Therefore, testing of an unselected population with immunological assays for anticardiolipin or anti-b2-GPI often results in a larger group of positive patients, reducing the diagnostic screening value of these assays for LA.

Clotting based assays are recommended for this application. The diluted Russel’s Viper Venom Test (dRVVT) is the first choice for the optimal laboratory detection of LA according to the guidelines. HEMOCLOT™ LA-S/LA-C, an optimised dRVVT assay with better sensitivity and specificity, is the ideal tool for screening of LA.

HEMOCLOT ™ LA-S /LA-C
HEMOCLOT ™ LA-S /LA-C is a set of dRVVT-reagents optimized for less
variation in performance and less interference from therapeutic anticoagulation.
HEMOCLOT ™ LA-S  (CK090K) is a green colored reagent, poor in phospholipid content,
for the screening for LA.
HEMOCLOT ™ LA-C (CK091K) is a pink colored confirm reagent with higher phospholipid
concentration expected to neutralize LA in the test plasma.
Both reagents contain a heparin neutralizing substance which makes the test insensitive
for heparin up to 1 IU/ml.

HEMOCLOT™ LA-S/C:

  • Improved sensitivity and specificity to LA
  • Abnormalities of the contact phase factors, deficiencies of FVII, FVIII and FIX
  • or their inhibitors do not affect the results
  • Less sensitive to Direct Oral Anticoagulants (DOACs) and Vitamin K Antagonists (VKA)
  • No interference of Heparin up to 1 IU/mL
  • Dedicated weak and high positive controls
  • Good stability

HEMOCLOT™ LA-S/C Performance

Intra assay Inter assay
Control Normal Pathological Normal Pathological
Test LA-S LA-S LA-C LA-S LA-S LA-C
n 30 30 30 14 14 14
Mean (sec) 37.6 89.4 42.2 36.6 89.2 41.5
SD (sec) 0.4 2.0 0.5 0.7 2.4 0.4
CV (%) 1.1 2.2 1.1 1.8 2.7 1.0

Quality Control
Hyphen BioMed offers quality control plasma for the use with HEMOCLOT™ LA-S and HEMOCLOT™ LA-C.
LA Control Plasma C1 is a weak positive control with a normalized ratio around 1,4. The C2 High positive control gives a ratio around 2,4. Lot specific information is provided with each kit.

Ordering information

Product Reference Package
HEMOCLOT LA-S CK090K Set of 6 x 1 ml
HEMOCLOT LA-C CK091K Set of 6 x 1 ml
LA Control Plasma Set (weak and high positive) SC081K 6 x (2 x 0.5 ml)
LA Control Plasma Weak SC082K 6 x 0.5 ml
LA Control Plasma High SC083K 6 x 0.5 ml

Other related products

Product Assay principle Reference Package
CEPHEN * Ready to use liquid aPTT reagent with a low sensitivity to LA. CK511K 6 x 1 mL
CK512K 6 x 2.5 mL
CK515K 8 x 5 mL
CK515L 8 x 5 mL
CEPHEN LS * Ready to use liquid aPTT reagent, sensitive to LA. CK521K 6 x 1 mL
CK522K 6 x 2.5 mL
BIOPHEN™ Normal plasma Lyophilized normal human citrated plasma, which
can be used for diluting plasmas for the diagnosis of LA.
223602 6 x 1 mL
223605 8 x 5 mL
ZYMUTEST™ Anti β2
-Glycoprotein I IgG-Isotype
an optimized ELISA designed for measuring autoantibodies to ß2-GPI of the IgG isotype (use of human ß2-GPI ) RK014A 96 tests
ZYMUTEST™ Anti β2
-Glycoprotein I IgM-Isotype
an optimized ELISA designed for measuring autoantibodies to ß2-GPI of the IgM isotype (use of human ß2-GPI ) RK014B 96 tests
 ZYMUTEST™ Anti β2
-Glycoprotein I IgA-Isotype
 an optimized ELISA designed for measuring autoantibodies to ß2-GPI of the IgA isotype (use of human ß2-GPI )  RK014C 96 tests
 ZYMUTEST ACA-APA,  IgG**  an optimized ELISA designed for measuring Anti-Cardiolipin/Anti-Phospholipid Antibodies IgG isotype RK029A
On-demand
96 tests
ZYMUTEST ACA-APA,   IgM** an optimized ELISA designed for measuring Anti-Cardiolipin/Anti-Phospholipid Antibodies IgM isotype RK029B
On-demand
96 tests
ZYMUTEST ACA-APA, IgA** (RUO) an optimized ELISA designed for measuring Anti-Cardiolipin/Anti-Phospholipid Antibodies IgA isotype RK029C
On-demand
96 tests

* Can be used for the aPTT ratio
** human ß2-GPI used as phospholipid cofactor

References

1. SSC/ISTH 2009 Updated guidelines for Lupus anticoagulant detection
2. GEHT and NCCLS/CLSI guidelines (H21-A5)
3. Thiagarajan P, Pengo V, Shapiro SS. The use of the dilute Russels viper venom time for the diagnosis of lupus anticoagulants.
Blood 1986, 68, 869-874.
4. Exner T, Papadopoulos G, Koutts J. Use of a simplified dilute Russels viper venom time confirms heterogeneity among “lupus
anticoagulants. Blood
5. Rausch J, Tannenbaum M, Janoff AS. Distinguishing lupus anticoagulants from antifactor antibodies using hexagonal phase II
phospholipids Thromb Haemost 1989; 62; 892-896.
6. Pengo V, Tripodi A, Reger G et al, Update of the guidelines for lupus anticoagulant detection. Thromb Haemost 2009.
7. Laboratory Testing for the Lupus Anticoagulant; Approved Guideline; CLSI guideline (H60-A)
8. Aiping Bai. b2-glycoprotein I and its antibodies involve in the pathogenesis of the antiphospholipid syndrome. Immunology Letters
186 (2017) 15–19
9. Moore G, Peyrafitte M, Dunois C and Amiral J, Evaluation of a new formulation dilute russell’s viper venom time for detection of
lupus anticoagulants. JTH 14, Suppl.1 Poster LUP04, ISTH SSC 2016