become prohibitively low at lower temperatures due to increasing
viscosity. Fortunately, toxicity control was found to be feasible
[105, 135–138] (see also Subheading 3.5), opening the way for
application of Fahy’s approach to a large range of living systems.
As Fahy was developing his approach to low cooling rate vitrification, Bill Rall was making fundamental cryomicroscopic observations, from 1980 to 1983, on mouse embryos that essentially
proved the hypothesis of James and Farrant that slow freezing can
concentrate cytoplasm to the point of enabling vitrification when
the cells are then cooled rapidly to lower temperatures [139–
141]. He was therefore immediately receptive to the idea of complete versus only intracellular vitrification upon hearing the first
major public presentation of this idea by Fahy in 1983 [134]. He
joined Fahy at the American National Red Cross’s Blood Research
Laboratory in Bethesda, MD soon thereafter to enable a collaboration intended to achieve the first clear demonstration of the survival
of living cells after vitrification and rewarming. The result, as
applied to mouse embryos in 1985, was, as is now well-known, a
success [60]. This demonstration finally introduced vitrification as a
potentially general method of cryopreservation. The next year,
further successes using human monocytes underscored the likely
general applicability of ice-free cryopreservation by vitrification and
added a number of additional fundamental observations of the
relationships between devitrification, cell survival, warming rate,
and intracellular ice crystal size and location [142].
1.4.4 Further
Developments: 1985–
Present
Since 1985, the number of reports on biological vitrification has
expanded exponentially (Fig. 1), and applications have been
numerous and diverse (see, e.g., [18, 20, 143, 144]). By 2013,
there were, for example, at least 1600 papers on embryo vitrification alone [20]. Obviously, it is impossible to review this entire
literature, but some necessarily limited and selected historical highlights are worth mentioning.
Vitrification achieved general scientific prominence in
1990–1992 with publication of the achievement of Drosophila
embryo vitrification by Peter Steponkus in Nature [64] and Peter
Mazur in Science [145]. The latter paper pointed out that Drosophila is a system for which success was possible only by vitrification
and not by slow freezing. The combination of high concentrations
of cryoprotectant and very high cooling and warming rates, as was
necessary in Drosophila due to its combined poor permeability to
cryoprotectants and high susceptibility to chilling injury, was
extended to overcome bovine oocyte chilling injury in 1996
[66]. Success was achieved under conditions that likely achieved
vitrification as well as with more dilute solutions that may not have
enabled oocyte vitrification. The latter observation led to many
other variations of technique that had in common the use of
38
Gregory M. Fahy and Brian Wowk
viscosity. Fortunately, toxicity control was found to be feasible
[105, 135–138] (see also Subheading 3.5), opening the way for
application of Fahy’s approach to a large range of living systems.
As Fahy was developing his approach to low cooling rate vitrification, Bill Rall was making fundamental cryomicroscopic observations, from 1980 to 1983, on mouse embryos that essentially
proved the hypothesis of James and Farrant that slow freezing can
concentrate cytoplasm to the point of enabling vitrification when
the cells are then cooled rapidly to lower temperatures [139–
141]. He was therefore immediately receptive to the idea of complete versus only intracellular vitrification upon hearing the first
major public presentation of this idea by Fahy in 1983 [134]. He
joined Fahy at the American National Red Cross’s Blood Research
Laboratory in Bethesda, MD soon thereafter to enable a collaboration intended to achieve the first clear demonstration of the survival
of living cells after vitrification and rewarming. The result, as
applied to mouse embryos in 1985, was, as is now well-known, a
success [60]. This demonstration finally introduced vitrification as a
potentially general method of cryopreservation. The next year,
further successes using human monocytes underscored the likely
general applicability of ice-free cryopreservation by vitrification and
added a number of additional fundamental observations of the
relationships between devitrification, cell survival, warming rate,
and intracellular ice crystal size and location [142].
1.4.4 Further
Developments: 1985–
Present
Since 1985, the number of reports on biological vitrification has
expanded exponentially (Fig. 1), and applications have been
numerous and diverse (see, e.g., [18, 20, 143, 144]). By 2013,
there were, for example, at least 1600 papers on embryo vitrification alone [20]. Obviously, it is impossible to review this entire
literature, but some necessarily limited and selected historical highlights are worth mentioning.
Vitrification achieved general scientific prominence in
1990–1992 with publication of the achievement of Drosophila
embryo vitrification by Peter Steponkus in Nature [64] and Peter
Mazur in Science [145]. The latter paper pointed out that Drosophila is a system for which success was possible only by vitrification
and not by slow freezing. The combination of high concentrations
of cryoprotectant and very high cooling and warming rates, as was
necessary in Drosophila due to its combined poor permeability to
cryoprotectants and high susceptibility to chilling injury, was
extended to overcome bovine oocyte chilling injury in 1996
[66]. Success was achieved under conditions that likely achieved
vitrification as well as with more dilute solutions that may not have
enabled oocyte vitrification. The latter observation led to many
other variations of technique that had in common the use of
38
Gregory M. Fahy and Brian Wowk