Chemistry: molecular biology and microbiology – Animal cell – per se ; composition thereof; process of...
Reexamination Certificate
2001-06-11
2003-09-09
Naff, David M. (Department: 1651)
Chemistry: molecular biology and microbiology
Animal cell, per se ; composition thereof; process of...
C435S366000, C435S389000, C435S404000, C435S407000, C424S093700
Reexamination Certificate
active
06617159
ABSTRACT:
BACKGROUND OF THE INVENTION
Bone and cartilage transplantation is an absolute need in reconstruction of bone and cartilage segments in plastic surgery, traumatic surgery or after the removal of neoplastic lesions, etc. Typically, material of human (autologous, from donors or from cadavers) or animal origin has been used for this purpose. Given the increased demand from clinicians for transplant tissues, the increased need for microbial safety in tissue transplantation, the advances in cell biology, cell differentiation and tissue engineering, the concept of rebuilding tissues from autologous or allogeneic cells expanded in vitro has become a growing field in the world of biomedical sciences. Cellular sources for skeletal repair include chondrocytes and cells committed to the chondrocyte lineage, and mesenchymal stem cells, the former specific for cartilage, the latter multipotential and therefore having the potential to be used to replace bone, cartilage and other tissues.
Mesenchymal stem cells (MSCs) are found in bone marrow as well as in blood, dermis and periosteum. Although these cells are normally present at very low frequencies in bone marrow, these cells can be isolated purified and culturally expanded, for example, as described in U.S. Pat. No. 5,486,359.
Typically, the ill vitro expansion of chondrocytes and MSCs takes place in culture medium supplemented with bovine serum or optimally with autologous serum from the patient. However, the presence of animal or autologous serum in chondrocyte and MSC cultures has certain disadvantages and limitations in view of the potential therapeutical applications of these cultures.
For example, serum is not the physiological fluid most cells closely contact in tissue in vivo. This is particularly true for chondrocytes that, in vivo, are embedded in their avascularized matrix and rely for their own growth and differentiation on various growth factors and cytokines acting in an autocrine/panacrine manner rather than diffusing from the distant bloodstream. Further, there is often high variability between animal serum batches. Extensive serum screening required to select the batch most representative of the in vivo inductive effects can be time-consuming and expensive The preparation of autologous serum from patients is also time consuming and supplies are limited. Animal serum can further potentially carry unknown pathogens with consequent risk of contamination for the patient.
Thus, serum substitutes for culturing cells for potential in vivo therapeutic applications is desirable.
SUMMARY OF THE INVENTION
The present invention provides a serum substitute for culturing cells in vitro using well defined factors able to support cell viability, proliferation and differentiation as effectively as serum containing medium. In a preferred embodiment, the cells are articular chondrocytes or mesenchymal stem cells.
In one aspect, the invention comprises a composition for the expansion of chondrocytes, comprising a minimum essential medium, a growth factor, albumin, a steroid, an antioxidant, an iron source, a fatty acid and/or a lipid source, and insulin. In a particularly preferred embodiment, the serum free growth medium for chondrocytes comprises Fibroblast Growth Factor 2 (FGF-2) as a growth factor, linoleic acid as the lipid/fatty acid source, ascorbic acid and &bgr;-mercaptoethanol as antioxidants, holo- and apo-transferrin as the iron source, and dexamethasone as a steroid. Optional ingredients can include cholesterol, trace metals such as selenium, and vitamins such as biotin and sodium pantotenate.
In another aspect, the invention comprises a composition for the maintenance of mesenchymal stem cells, comprising a growth factor, albumin, a steroid, an antioxidant, an iron source, a fatty acid and/or a lipid source, one or more vitamins, one or more trace metals, and Insulin Growth Factor I (IGF-1), in combination with a minimum essential medium. In a particularly preferred embodiment, the serum free growth medium for mesenchymal stem cells comprises FGF-2, Leukemia Inhibitory Factor (LIF) and Stem Cell Factor(SCF) as growth factors, sodium pantotenate and biotin as vitamins, and selenium as a trace metal.
REFERENCES:
patent: 5405772 (1995-04-01), Ponting
patent: 5962325 (1999-10-01), Naughton et al.
patent: WO96/39487 (1996-12-01), None
patent: WO96/40866 (1996-12-01), None
patent: WO97/33978 (1997-09-01), None
patent: WO98/04681 (1998-02-01), None
Quarto R et al.: “Proliferation and differentiation of chondrocytes in defined culture medium: effects of systemic factors” Bone, vol. 17, No. 6, Dec. 1995, p. 558.
Pain B et al.: “Long-term in vitro culture and characterisation of avian embryonic stem cells with multiple morphogenetic potentialities” Development, GB, Colchester, Essex, vol. 122, Aug. 1996, pp. 2239-2248.
Cancedda Ranieri
Dozin Beatrice
Consorzio per la Gestione del Centro di Biotechnologie Avanzate
Naff David M.
Nixon & Vanderhye P.C.
Ware Deborah K.
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