Judith Graham Pool and the discovery of cryoprecipitate

The history of concentrated factor VIII (FVIII) beginsin the early 1940s, when Edwin J. Cohn [1] pioneeredfractionation of plasma with various proportions ofethanol. His ‘fraction I’ contained ﬁbrinogen and alsoFVIII (but methods of assay had not yet been devel-oped) and von Willebrand factor (which had not yetbeen deﬁned). The utility of fraction I in haemophiliawas demonstrated early [2] and modest amounts wereused in developed countries throughout the 1950s and1960s, but its sterile production required a large labo-ratory. A commercial version became available in theUnited States as a concentrate of ﬁbrinogen, rich inFVIII; in one measurement [3], the ratio of FVIII tototal protein was sevenfold that of native plasma. In1965, it cost about 17.5 cents (U.S. $ 0.175) per FVIIIunit [4]. Meanwhile, community blood banks wereseparating and freezing plasma from whole blood forlocal use. Blood banks in the United States generallyset the price of plasma low, as a by-product of wholeblood collection, so it was widely used. The hemostat-ic efﬁcacy of whole plasma was sub-optimal becauseonly a limited volume could be infused at one time.In the early 1960s, Cutter Laboratories in Berkeley,California, and its scientists were trying to make animproved concentrate of FVIII, with help from north-ern California ‘clotters’, including Paul M. Aggeler ofthe University of California at San Francisco andJudith Graham Pool of Stanford University. I had thefelicity of being a haematology Fellow in Dr. Aggeler’slaboratory from 1962 to 1965, which were headyyears in the history of haemophilia treatment.The ﬁrst FVIII concentrate I ever saw, in 1963, wasan experimental, lyophilized product from Cutter Lab-oratories. We were planning to extract all remaining,very rotten teeth from a malnourished man withsevere haemophilia A, to prepare him for dentures.We dreaded the event: a similar patient, who had thesame operation a year earlier, was hospitalized for2 weeks, needing several bags of plasma per day plusoccasional red blood cell transfusions. With the pre-cious new concentrate, however, our patient’s hemo-stasis during dental extractions was perfectly normal.Cutter could not produce much of this marvellousmaterial because the yield of concentrated FVIII fromplasma was low. Enter Dr. Judith Graham Pool.She had earned her Ph.D. in physiology from theUniversity of Chicago in 1946 and had joined the fac-ulty of Stanford University in 1953, investigatingcoagulation with particular attention to FVIII. WithJean Robinson, she had developed the ‘two-stage’assay for FVIII in 1959. In the early 1960s she usedthat method to assay FVIII in plasma fractions pre-pared by Cutter’s Drs. Albert Pappenhagen andEdward Hershgold. Their starting material was pooledplasma, frozen in large containers, which they thawedcautiously. They knew that the potency of FVIII inplasma dwindled at room temperature, so they werecareful not to thaw the plasma completely. But Dr.Pool found very little FVIII in their thawed superna-tant. She then tested the small amount of unthawed,ﬁbrous-looking paste at the bottom of the containers,and, in 1964, found the FVIII [5].The genius of Dr. Pool was her leap from that labo-ratory observation to the practical idea of using thelast-to-thaw property of FVIII to separate ‘cryoprecipi-tate’ from whole plasma in an ordinary blood bank,re-freezing the small volume in its own sterile plasticbag and storing bags in a freezer so that eventuallyseveral could be given to a patient at one time [4].Meanwhile, the thawed plasma could be used forextraction of other plasma proteins. The method wasso simple, and cost so little for the additional materi-als, that it was rapidly copied by blood banks aroundthe world. Cryoprecipitate became widely availablenot only for patients with haemophilia A or vonWillebrand disease but also for patients deﬁcient inﬁbrinogen or factor XIII. It was a great, miraculousgift to the world. Many tens of thousands of patientshave beneﬁtted.Meanwhile, more highly concentrated commercial,lyophilized FVIII preparations were developed, usingvarious technologies (often including cryoprecipita-tion). The ﬁrst was licensed in the USA at the end ofthe 1960s and then cost ten cents (U.S.$0.10) perFVIII unit in Los Angeles. We quickly adopted its useand, by 1970, started to introduce our haemophiliapatients to self-infusion at home. Our local bloodbank had switched from the use of glass bottles forblood collection to plastic bags only in the late 1960s,delaying the development of cryoprecipitate. Further-more, instead of charging only the incremental costsof the additional processing required to extract