[Studies on the vitality of human bone marrow during collection and deep-freeze preservation]. / Untersuchungen zur Vitalität von Human-Knochenmark bei der Gewinnung und Tieftemperaturkonservierung.

The cryoprotective effect of dimethylsulfoxide, glycerol and polyethylenglycol during freezing and thawing of human bone marrow was investigated by eosin staining test, an acridinorange fluochrome staining test and by RNA- and DNA-synthesis tests. In these tests the overall yield of vital nucleated cells, referred to the number in the absence of cryoprotectants and freezing and thawing, amounted to 50% with dimethylsulfoxide, 30% with glycerol, and 10% with polyethylenglycol. With dimethylsulfoxide and glycerol the loss of vital nucleated cells is almost entirely due to the addition of cryoprotectants. Polyethylenglycol freezing and thawing also leads to a great loss of vital nucleated cells. The results with dimethylsulfoxide show that the currently employed techniques of punction, preparation, freezing and thawing of bone marrow are suitable for clinical application.

[A test system for the measurement of cellular RNA-synthesis in the human bone marrow]. / Ein Testsystem zur Messung der zellulären RNS-Synthese von humanem Knochenmark.

A test for the cellular RNA-synthesis (incorporation of 3H-uridine in the RNA) of human bone marrow has been standardized with respect to the time of incorporation, the number of cells and the concentration of 3H-uridine. The following parameters were estimated for 500 microleter standard assay and 100 microleter aliquots for the determination of the radioactivity: time of incubation 80 min, number of nucleated cells 8 - 10(5), concentration of 3H-uridine 8,3 - 10(-6) M. Actinomycin D inhibits the RNA-synthesis to 90% in a concentration of 1.2 - 10(2) microgram/ml. The test appears generally applicable for the determination of the vitality of bone marrow after cryopreservation, the testing of cryoprotectants and haematotoxic substances and the control of the reaction of the bone marrow during chemical- or irradiation treatment of tumors.

[Cellular test for RNA-synthesis in rat bone marrow and its use in testing cryoprotective and toxic agents]. / Ein zellulärer RNS-Synthese-Test mit Rattenknochenmark und seine Anwendung bei der Testung von Kryoprotektiva und zur Erfassung von Schadstoffen

A system for the measurement of the RNA-synthesis of bone marrow cells of the rat has been developed and the incorporation of [3H]-uridine into the cellular RNA has been standardized with respect to the time of incubation, the concentration of [3H]-uridine and the number of cells. A plateau of the incorporation of [3H]-uridine into the RNA is reached after 20 min of incubation and is interpreted as the expression of a steady state in synthesis and degradation of the cellular RNA. A constant labelling of the RNA is reached above 8.3 with 10(-6)M [3H]-uridine. The optimal cell number in the 500 mul standard assay is 4 with 10(6). Actinomycin D inhibits the RNA-synthesis to 94% in a concentration of 1.2 with 10(2) mug/ml. The cryoprotectants dimethylsulfoxide, polyethylene-oxide and glycerol and the potential haematotoxic substances dichlorodiphenyltrichloroethane and gamma-hexane were tested in this system. 5% dimethylsulfoxide and 10% polyethylen-oxide in Eagle's-medium with ethylendiamintetra-acetate do not influence the RNA-synthesis. 5% glycerol reduces the incorporation of [3H]-uridine into the cellular RNA to about 30%.