Human Factor VIII Prepared by Cryoprecipitation¹

Abstract

When previously frozen normal human plasma is thawed a t 4"C, about 3% of the plasma proteins remain insoluble. These cryoproteins or cryoprecipitate contain a certain amount of fibrinogen as reported b y WARE et al. [41] in 1947, and, as observed b y POOL and ROBINSON [26] in 1959, display high antihaemophilic A potency. I n 1954, BRINEHOUS [6] had already reported that partially purified factor VIII was insoluble in the cold state. I n 1964, POOL et al. [24, 251 proposed a method of preparation suitable for therapeutic use, which was later considerably simplified [21, 27, 281.This process is currently used on a large scale in the United States and various European countries with only slight variations in the method of preparation [8, 10, 34, 37, 421. Composition and Characteristics of Cryoprecipitate PreparationsTwo t o 3 ml of cryoprccipitate, separated from 250 t o 320 ml of citrated plasma, are dissolved in 7 t o 20 ml of saline, citrated saline (five volumes trisodium citrate a t 3.8 g/lOO ml for one volume of 0.15 M NaCl) or supernatant plasma.The protein content of the cryoprecipitate solutions prepared in the various centres is given in table I. Electrophoretic and immunoelectrophoretic tests reveal the presence of practically all the normal plasma proteins in comparable proportions, except for fibrinogen whose concentration is particularly high [3, 15, 331 (table 11).Quantative determinations of the coagulation factors show potencies likewise proportional t o the concentrations of other proteins for factors 11, VII, IX, X, XI and XI1 (table I). Factor V, which is highly labile in storage, may show reduced potency. On the other 1 Invited paper. 2 H U t+ cc 40. VREEKEN, J. ; KRWNEN, H. and DEGGELER, K. : Round the table discussion on the rational of a cryoprecipitate preparation and its clinical evaluation in haemophilia (Brussels, June 23rd, 1967). 41. WARE, A. G.; GUEST, M. M. and SEEGERS, W. H.: Fibrinogen: with special reference to its preparation and certain properties of the product. Arch. Biochem. 13: 231-236 (1947). 42. WEAWER, R. A.; GABRIEL, D. A. and LANGDELL, R. D.: Concentrated antihemophilic factor (AHF) from outdated blood. Transfusion 7:

Variables Involved in Cryoprecipitate Production and their Effect on Factor VIII Activity

“…Advantages from rapid thawing of the frozen plasma in water baths a t temperatures of 3°C and 8°C have been described by Brown et al (1967), Masure (1969), Slichter et al (1976) and Vermeer et al (1976. Combining rapid thawing with shaking (Burka et al, I97Sb;Margolis, 1976) and with syphoning (Mason 1978) has also led to increased yields of factor VIII in cryos.…”