OD-07. Influence of the qualitative characteristics of thrombocyte concentrate on its clinical efficacy in the treatment of oncohematological patients

Summary

Platelets play a key role in the process of blood clotting after vascular injury, regulating the wound healing process. Platelet concentrate (PCT) isolated from donor blood is a suspension of viable and hemostatically active platelets in plasma and with the addition of a platelet storage solution, prepared by serial centrifugation of preserved blood or by the method of platelet apheresis of blood from single donors. Platelet concentrate obtained by plateletapheresis is a CT scan prepared from, at least, 1.5 L of blood from an individual donor with a blood cell separator (Trima Accel, MCS, Com Tec) Such PCT contains at least 2.0*10¹¹ platelets in 200-300 ml of plasma, or in 150-180 ml of solution for platelet storage, at a volume of 240 ml. From 2013 to 2020, the number of hematopoietic stem cell transplants was increased, thus requiring more platelet concentrates. Harvesting of apheresis platelets provided 4098 therapeutic units (200*10⁹) in 2016, and this figure increased to 6300 therapeutic doses in 2019. When choosing a component for transfusion, the following factors must be taken into account: the number of platelets in the donor, the number of platelets in the component, the immature platelet fraction (IPF) in donor blood, and IPF numbers in the platelet concentrate. The immature platelet fraction (IPF) is a more accurate marker of platelet formation and reflects the percentage of immature platelets from their total number. This index denotes newly formed platelets with an increased content of RNA, the number of which correlates with the activity of megakaryocytes. Immature platelets are more reactive than mature ones and have an increased prothrombotic potential. Young immature platelets, which have a high density and residual amount of RNA (traditionally called reticulated platelets), are more reactive because they are able to form and release more thrombogenic substances, which are important markers of platelet activation.

Materials and methods

The study involved 50 donors, with male/female ratio of 45/5, the age range was from 18 to 41 years old, with blood platelet counts from 200*10⁹ to 400*10⁹/l. The level of IPF in the donor before donation and in the platelet concentrate was determined. From the data obtained, the following conclusions can be drawn: there is a direct relationship between IPF in the harvested platelet component and IPF in the donor blood. With IPF> 15.03 in the donor, the IPF in the component will be 59.30 (p <0.05).

Conclusion

It is advisable to procure platelet concentrate from donors whose IPF is >15.03, or to take this into account when selecting donors. At IPF level exceeding 15.03, the platelet increase after transfusion is higher. It is necessary to continue further research on the relationship between the donor IPF level and the increase in the patient’s platelet level.

Keywords

Platelets, platelet concentrate, immature platelet fraction.