Effect of the secretome of horse mesenchymal stem cells on platelet aggregation in vitro

The effect of the equine MSCs secretome on the ability to induce thrombosis in vitro was studied by visually assessing platelet aggregation under the action of this drug on a slide using the A. S. Shitikova method, observing the process under phase contrast. The effect of secretome on thrombosis in vitro was determined on platelet plasma isolated from horse blood with the anticoagulant sodium citrate. Saline solution (control 1), 10.0% calcium chloride solution (control 2), a secret in the proportion of 10 parts of the volume of plasma enriched with platelets to 1 part of the secretome (experiment 1), a secret in the proportion of 20 parts of the volume of plasma enriched with platelets to 1 part of the secretome (experiment 2) were added to tubes with platelet plasma, a secret in the proportion of 20 parts of the volume of plasma enriched with platelets to 1 part of the secretome and 10.0% calcium chloride solution (experiment 3). After adding control and experimental preparations to platelet plasma samples, 10.0 µl of the mixture was microscoped at X400 magnification using phase contrast. As a result of our research, data were obtained indicating that the secretome of horse MSCs lacks the ability to induce platelet aggregation. Platelet-rich plasma obtained from horses (n=10) with sodium citrate showed no signs of aggregation, unlike platelet-rich plasma with sodium citrate activated with calcium chloride. When secretome was added at concentrations of 10 to 1 (10 parts of platelet-rich plasma volume to 1 part of secretome) and 20 to 1 (20 parts of platelet-rich plasma volume to 1 part of secretome), platelet aggregation was also not observed. At the same time, when calcium chloride was added to a platelet-enriched plasma sample with the addition of secretome, platelet aggregation was within the normal range.

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