The use of pectins as part of a cryoprotective solution for long-term storage of human platelet concentrates.

BACKGROUND: Pectins have unique properties and great potential to become an indispensable component of cryoprotective environment for platelet freezing. OBJECTIVE: To investigate the possibility of including pectins (apple pectin AU-701, tanacetan) into the composition of a cryoprotective solution for platelets during low-temperature storage. MATERIALS AND METHODS: Samples of platelet concentrates (PC) were frozen under the protection of complex solutions and stored in an electric freezer at -80 degree C for 1 and 6 months. RESULT: The study showed that of the basic cryoprotectants, the best effect in the preservation of PC was with dimethylacetamide (DMAC). The use of pectins as an additive to the base solution of DMAC statistically improves the preservation of PC after exposure to low temperatures (-80 degree C) for 30 and 180 days. CONCLUSIONS: We conclude that DMAC is more promising as a basis for the development of a new combined cryoprotectant for PC freezing. Moreover, the chemical structure of pectin determines the level of its cryoprotective action in relation to the preservation of PC. doi.org/10.54680/fr22610110312.

Application of Pectin From Rauvolfia serpentina (L.) Benth to the Cryopreservation of Human Leucocyte Cell Suspensions.

　　BACKGROUND: Due to their valuable medicinal properties and high physiological activity, plant polysaccharides are currently being extensively studied. OBJECTIVE: The present study aims to investigate rauwolfian (pectin for Rauvolfia serpentina) supplementation on human leukocytes cryopreservation. We determined the сharacteristics of leukocytes undergoing freezing with pectin at different temperatures. METHODS: Donor leukocytes were frozen under the protection of comprehensive cryoprotectant solution and stored in electrical freezers (-20C, -40C, -80C). RESULT: A regular decrease of all values starting from a higher temperature (-20С) through to the lower temperature (-80С) was identified. The study showed that pectin rauwolfian stimulated both the oxygen-independent and the oxygen-dependent killer response. We also found that the oxygen-dependent neutrophil killer effect was reduced as the storage temperature was lowered. It was determined that the LPO levels in the cells with added pectin-containing solutions remained the same before freezing, while their antioxidant activity positively increased, which is beneficial for neutrophils for their further freezing to -20C, -40C and -80C. CONCLUSIONS: The results of the study make it possible to assume that rauwolfian, a pectin extracted from Rauvolfia serpentina, has an exocellular protectant effect as part of cryopreservative solution on human white blood cells stored at different low temperatures. The versatility of the substance is probably due to the degree of the macromolecule branching, in particular, the structure of carbohydrate side chains, which contain a large number of hydroxyl groups.

Effect of In Vitro Cold Exposure on Phagocytic Activity of Human Peripheral Blood Neutrophils.

Experiments on peripheral blood leukocytes from healthy donors using the biochemiluminescent method demonstrated the possibility of in vitro modulating phagocytic activity of neutrophils by cold exposure. Cold exposure at 2°C for 30 min increased phagocytic activity of cells, while slow cooling to -2°C reduced it.

The use of inert gas xenon for cryopreservation of leukocytes.

We studied the possibility of cryopreservation of human blood nuclear cells under protection with inert gas xenon. A method for inducing clathrate anabiosis of leukocytes was developed that preserved the cells for practical use in biology and medicine.

Influence of pectins on NADPH oxidase and phagocytic activity of neutrophils during cryopreservation.

NADPH oxidase activation was studied by detecting the reactive oxygen species (ROS) and the dynamics of neutrophil phagocytic activity in blood before freezing and one day after exposure to -20 degrees C in the presence of pectic polysaccharides. Pectins (excluding lemnan) were found to increase the phagocytic activity of neutrophils, promote the formation of ROS in these cells and enhance NADPH oxidase activity in the following order: bergenan, comaruman, lemnan, apiuman, and potamogetonan. Cryoprotective action of lemnan and comaruman was proposed to be related to their unique chemical structures.

[Preservation of leukocytes at moderately low temperature].

It was shown that the use of little toxic cold-protective containing the glycerol protector endocellular action, HES--protector exocellular action, and "restored" component of the succinate 3-hydroxy-6-methyl-2- ethylpyridine preserves nuclear blood cells in a viable condition at -40 degrees C.

[Leucocytes conservation in the near-zero temperature].

The intensive metabolism and fast exhaustion of an energy potential of nuclear blood cells at positive temperatures essentially reduce terms of their storage in a viable condition. However for the clinical purposes given thensfusion environment is the extremely necessary. The popular method of preservation of cells at ultralow temperature (-196 degrees C) is limited in application since assumes use of the liquid nitrogen, the special equipment, trained engineering personnel. The work is devoted to development effective and simple in execution of a method of preservation of leukocytes in conditions of temperatures about zero (+2 degrees--0 degrees C) with use of a household elecrorefrigerator and new cryopreservation a solution.

Use of choline chloride for leukocyte cryopreservation (-40 degrees C).

Choline chloride in complex with the main cryophylactic (1,2-propanediol) preserves morphological integrity and functional activity of blood nuclears after freezing to -40 degrees C by the exponential program.

A new method for preservation of viable leukocytes at near-zero temperatures.

We propose a new effective, available, and economic method for preservation of leukocytes at near-zero temperatures for 6 days using an original protecting solution.

Creation of a gelatin-based solution for preservation of leukocytes.

A new effective and available method is proposed for preservation of human blood leukocytes at supercooling temperature (-10 degrees C). The method consists in induction of cold hypobiosis under protection of an original antifreeze protecting solution containing glycerol (cryoprotector), mexidol (antioxidant and membrane stabilizer), and gelatin preparation (modegel or gelatinol) as the solvent. No washing of the solution from the biological object before its intravenous injection is needed; the solution preserves morphological integrity of cells and their functional activity at a high level for 12 days.