Akhatova Y. Influence of the cord blood low-molecular (below 5 kDa) fraction on energy metabolism of frozen-thawed leukocytes

The research object was the functional and energy state of leukoconcentrate cells after cryopreservation with DMAс. The research aim was to study mechanisms of the cattle cord blood low-molecular fraction (below 5 kDa) influence on the energy state of human blood leukoconcentrate cells after cryopreservation. The research methods were light microscopy, cryopreservation, centrifugation, biochemical, immunological and electrochemiluminescent analyses, gel filtration using Sefadex G-25 Coarse, ultrafiltration, lyophilization, cytochemical staining of cell smears, cytophotometry and methods of statistical processing of the results. The equipment comprised a software freezer ZP 10 (Special Technology Design Bureau of IPC&C of the NASU); hemolyuminometr ATP-Luminometer (LKB-1250, Sweden); automatic analyzer Elecsys 1070/2010, Modular Analytics E170 and Cobas C311 (Hoffmann-La Roche, Switzerland). The damaging effect of low temperatures on leukoconcentrate cell bioenergy as well as the recovery effect of the cattle cord blood low-molecular fraction (below 5 kDa) as part of rehabilitating medium for leukoconcentrate cells after cryopreservation with 5% DMAc was studied. Evidence of energy disbalance of leukoconcentrate cells after cryopreservation was obtained. For the first time it was shown that the cord blood low-molecular fraction (0.15 mg/mL) activated glycogenolysis, increased contents of adenylic nucleotides (ATP, ADP and AMP) and glucose in leukoconcentrate cells after cryopreservation that resulted in an increase in the functional activity of these cells. It was also shown that the cord blood low-molecular fraction (below 5 kDa) contained energy substrates and metabolites, hormone regulators of metabolism and macro- and micronutrients. The research results are of scientific and practical importance for the establishment of leukoconcentrates stores and their long-term storage for further clinical application. The results can be used for development of new technologies and improvement of existing ones of cell suspension cryopreservation as well as for improvement of leykokontsentrate quality prior to transfusion.