Chemistry: molecular biology and microbiology – Micro-organism – per se ; compositions thereof; proces of... – Preserving or maintaining micro-organism
Patent
1997-12-18
2000-04-25
Naff, David M.
Chemistry: molecular biology and microbiology
Micro-organism, per se ; compositions thereof; proces of...
Preserving or maintaining micro-organism
435243, 435248, 435374, 435395, 435397, 435401, 435402, 435404, 435410, 435420, C12N 100, C12N 104, C12N 500
Patent
active
060543116
DESCRIPTION:
BRIEF SUMMARY
The present invention relates to a method of treatment of living cells, in particular a method of cryopreservation.
BACKGROUND OF THE INVENTION
Cryopreservation provides a means for the stable, long-term storage of biological plant and/or animal and/or microbial cells, tissues or organs, including plant zyotic or somatic embryos and meristems at ultra-low temperatures, eg 77.degree. K. (-196.degree. C.). For example, such a technique circumvents reduced morphological competence (totipotency), genetic change and secondary product formation of plant cell cultures associated with long-term culture at normal growth temperatures.
Cryopreservation comprises many steps, of which controlled freezing is only one; successful recovery is dependent on the combined effects of cryogenic and pre- and post-freeze treatments. The transition of tissues between low and physiologically normal temperatures and oxygen tensions causes respiratory imbalances which stimulate the production of toxic oxygen radicals as described for example by Fuller, B J, Gower, J D and Green, C J in "Free radical damage and organ preservation: fact or fiction", Cryobiology," 25, 377-393 (1988).
Physiological investigations of cryopreserved cells have shown that respiratory impairment occurs primarily, but not exclusively, during early post-freeze thaw recovery as described for example by Cella R, Colombo R, Galli M G, Nielsen M G, Rollo F and Sala F in "Freeze-preservation of rice cells: a physiological study of freeze/thawed cells", Physiologia Plantarum 55, 279-284 (1982).
It is an object of the present invention to provide a method for the recovery of living cells which have been subjected to cryopreservation in which the aforementioned respiratory impairment is reduced, whereby normal cell growth and function is promoted.
SUMMARY OF THE INVENTION
According to the present invention there is provided a method for the recovery of living cells which have been subjected to cryopreservation which comprises thawing the cells and then supporting them in a gas permeable medium comprising at least one polyfluorinated compound.
DESCRIPTION OF THE INVENTION
The polyfluorinated compound is preferably gassed, eg with oxygen where oxygenation is required.
The living cells to be treated by the method according to the present invention may comprise plant and/or animal and/or microbial cells. The cells may be present as individual cells, cell cultures, tissues, meristems, differentiated organs (eg floral parts), specialized cells (eg pollen grains) or subcellular components (eg protoplasts).
The living cells may advantageously be maintained in contact with a medium comprising an oxygenated polyfluorinated compound during other stages of the cryopreservation process in addition to the post-thaw recovery stage, for example during the cryoprotection, freezing and storage, recovery and post-recovery establishment of growth stages as described below.
The polyfluorinated compound may comprise a hydrocarbon in which at least 50 per cent of the hydrogen atoms have been substituted by fluorine atoms. The polyfluorinated compound desirably is a perfluorocarbon or derivative thereof collectively referred to herein as "PFCs". Particularly preferred polyfluorinated compounds for use in the method according to the present invention include perfluorocarbons such as perfluoroalkanes, perfluoro(alkylcycloalkanes), perfluoro(alkylsaturated heterocyclics) and perfluoro(tert-amines) or mixtures thereof. These compounds are capable of absorbing large amounts of oxygen and other respiratory gases and are substantially inert and non-toxic. Inert additives, eg thickeners or gels, eg silicones may be added to the perfluorocarbon(s). Examples of suitable PFCs include perfluorodecalin, perfluorophenanthrene, perfluorooctyl bromide, perfluorobutyltetrahydrofuran and perfluorotributylamine.
PFCs can dissolve substantial volumes of respiratory gases and beneficially enhance, for example, oxygen supply to cells. The use of a support medium which comprises one or more polyfluorinated
REFERENCES:
patent: 4251995 (1981-02-01), Pert et al.
patent: 4464337 (1984-08-01), Zelman
patent: 5326356 (1994-07-01), Della Valle et al.
patent: 5650164 (1997-07-01), Della Valle et al.
patent: 5658331 (1997-08-01), Della Valle et al.
Urushihara et al, "A Comparison Study of Rat Pancreas Preservation Using Perflurochemical . . . " BIOMAT pp. 933-936, 1992.
Kuroda et al, "The Mechanism of Action of the Two-Layer (Euro-Collins Solution/Perflurochemical) Cold-Storage Method . . . " Transplantation vol. 53, pp. 992-994 #5. XP000578436, May 1992.
Kuroda et al, "Mechanism of Oxygenation of Pancreas During Preservation By A Two-Layer (Euro-Collins, Solution/Perflurochemical) Cold . . . " vol. 49, 694-96 #4, Apr. 1990.
Kohe J. Med. Sci., Sakai et al "A Novel Syst. for Sm. Bowel Pres. . . . " vol. 41, 33/46 pp. 33-46, Jun. 1995.
Davey Michael Raymond
Lowe Kenneth Charles
Power John Brian
F2 Chemicals Limited
Naff David M.
Ware Deborah K.
LandOfFree
Recovering cryopreserved cells using gassed polyfluorinated comp does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Recovering cryopreserved cells using gassed polyfluorinated comp, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Recovering cryopreserved cells using gassed polyfluorinated comp will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-992548