Recurrent Genetic Abnormalities in Human Pluripotent Stem Cells: Definition and Routine Detection in Culture Supernatant by Targeted Droplet Digital PCR.

Genomic integrity of human pluripotent stem cells (hPSCs) is essential for research and clinical applications. However, genetic abnormalities can accumulate during hPSC generation and routine culture and following gene editing. Their occurrence should be regularly monitored, but the current assays to assess hPSC genomic integrity are not fully suitable for such regular screening. To address this issue, we first carried out a large meta-analysis of all hPSC genetic abnormalities reported in more than 100 publications and identified 738 recurrent genetic abnormalities (i.e., overlapping abnormalities found in at least five distinct scientific publications). We then developed a test based on the droplet digital PCR technology that can potentially detect more than 90% of these hPSC recurrent genetic abnormalities in DNA extracted from culture supernatant samples. This test can be used to routinely screen genomic integrity in hPSCs.

Effects of argatroban, danaparoid, and fondaparinux on trombin generation in heparin-induced thrombocytopenia.

There is no in vitro data on the comparison of the effects of danaparoid, argatroban and fondaparinux on thrombin generation in patients with heparin-induced thrombocytopenia. It was the study objective to compare the in vitro anticoagulant potential of argatroban, danaparoid and fondaparinux using a thrombin generation assay TGA on a mixture of control platelet-rich plasma (PRP) and HIT patient platelet-poor plasma (PPP). The plasma of seven patients with a clear HIT diagnosed at our institution was selected. Mixtures of donor PRP and patient PPP were incubated with unfractionated heparin 0.2 U.mL⁻¹, argatroban at 600 ng.mL⁻¹, argatroban at 400 ng.mL⁻¹, danaparoid at 0.65 IU.mL⁻¹ and fondaparinux at 1 µg.mL⁻¹. Thrombin generation was assessed by calibrated thrombinography. The percentage of inhibition of the endogenous thrombin potential observed with argatroban at 600 ng.mL⁻¹ was statistically significantly higher compared with those observed with fondaparinux (median: 53.6% vs. 3.9%; p=0.031) but not compared with argatroban at 400 ng.mL⁻¹ and danaparoid. The percentage of inhibition of the thrombin peak observed with argatroban at 600 ng.mL⁻¹ was statistically significantly higher compared with those observed with danaparoid (median: 71.2 vs. 56.8; p=0.031) and fondaparinux (mean: 71.2 vs. 30; p=0.031) but not with argatroban at 400 ng.mL⁻¹. In conclusion, the in vitro effect of argatroban and danaparoid on thrombin generation seems to corroborate the results of clinical studies of these drugs in the treatment of HIT in term of efficiency. Fondaparinux showed a very small effect on thrombin generation evaluated by calibrated thrombinography.