PubMed · 431572
The source did not provide an abstract. Follow the original record for more information.
Explore connections, maps & timelines
C F Högman, K Hedlund, H Zetterström. 1979-04-26. Red-cell suspensions.. https://doi.org/10.1056/nejm197904263001713
Cite the original work for its findings. Save a collection to share your selection of sources.
KEEP EXPLORING
Explore the source record for details and available documents.
A differential scanning calorimeter was used to study the thermal behavior of glycerol-water solutions (binary system) and the more complex glycerol-based cryoprotective solutions that are used clinically in order to examine the cryoprotective role of glycerol in preserving frozen red blood cells. The melting and glass transition temperatures for the clinically used cryoprotective solutions were as expected, based on the nonequilibriumphase diagram for cryoprotective solutions incorporating isotonic phosphate-buffered saline. Two zones were identified in which solidification occurred without the formation of ice crystals: a glassy state that is crystallographically amorphous was found for glycerol concentrations between 40 and 55% in the binary system and between 45 and 60% in the complex system; a glassy state in the complete absence of ice was found at glycerol concentrations greater than 55% for the binary system or 60% for the complex system. In clinical practice, cryoprotectants are used at initial concentrations lower than those at which these two glassy states occur but there is an increase in the effective glycerol concentration inside and outside the cells as ice forms during the freezing process.
Cryopreservation of cells appears to be a potential method of comparing chemotaxis of lymphocytes collected from different anatomical sites at one time in a single assay. Migration of cryopreserved lymphocytes from swine in the absence (spontaneous migration) or presence of N-formyl-methionyl-leucyl-phenylalanine (fMLP, induced migration) was compared to that of fresh lymphocytes, originating from inguinal (ILN) and mesenteric (MLN) lymph nodes, respectively, using a 48-well microchemotaxis chamber. Cryopreservation did not affect the optimal concentration of fMLP for maximal induced migration and did not impair the chemoattractant activity of fMLP as shown by checkerboard assay. However, cryopreservation reduced the extent of fMLP-induced migration by affecting the spontaneous motility of cells, an effect which was greater for MLN than for ILN cells. This reduction was not related to a loss of cell subset and is in keeping with the view that spontaneous and induced migration involve distinct mechanisms. Thus cryopreservation may be of general use to study the migration of lymphocytes by reducing the differences in spontaneous migration of lymphocytes from different sites.