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本帖最后由 qianqianlaile 于 2011-3-21 11:29 编辑 4 @( y$ n2 R& h. ]
# D7 j5 `% e/ n0 }4 ?' rINTRODUCTION
6 ^, N5 ]/ ~- y h! v* rCell therapy has tremendous potential in regenerative medicine, yet, there are concerns in " f0 R9 \& A0 j# S/ ~
the utility of cell therapy due to questions regarding different cell harvest and cultivation
. N- m6 D) @) F% [4 e/ smethods (Haack-Sorensen et al., 2008; Mannello and Tonti, 2007). Bone marrow derived
9 H9 Z: T+ x; U+ Ostem cells have been identified for a number of years, and there are a number of
0 |4 ?# y/ H. _3 ?& q; }4 ?ongoing clinical trials exploring the safety and efficacy of their use for a number of 9 g4 X! _; i& u7 l
clinical applications (Battiwalla and Hematti, 2009; Sadan et al., 2009; Satija et al.,
" A$ j1 ] _# c- k% }4 A. C. Q2009). There has been an increased interest in recent years in the potential of oral-
" j% R W6 H) W8 @7 v8 O. w2 B4 o; |derived stem cells for cell therapy, primarily because they can be derived from a readily 9 C b6 ]% Q6 p4 Y' F: R/ h
available source, extracted teeth (Gronthos et al., 2000; Miura et al., 2003; Seo et al., 4 L% r# S) ?5 V$ n; R k0 B- S& y
2004). These cells exhibit multipotency and regenerative capacities characteristic of 9 \6 E1 Q- c7 l, r. R
mesenchymal stem cells (Batouli et al., 2003; Shi et al., 2005) and have the capacity to
/ l. }* S5 p7 r: ^) b/ Lrepair and regenerate tooth structures in vivo (Krebsbach and Robey, 2002; Mao et al., 2006). $ H$ ^- c0 _7 e6 X8 }7 z; L
Because oral-derived stem cells have been more recently identified, clinical , D6 E% g- u' e* W
protocols are still being developed for their use. Regardless of the specific protocol
; c9 a3 Y3 S4 S2 nused, most current cell therapy approaches rely upon ex vivo cell expansion in order to * h- m" W$ O5 u8 Z- [
produce sufficient cell numbers for transplantation. Though a wide variety of protocols
& X: A& P% Z# ?4 V* A w4 xand culturing methods exist, one common aspect to most of them is the inclusion of
) @ [- m( [( kanimal sera for cell expansion, in that it contains a rich source of nutrients and growth 1 I, ^" G k# i2 X( o
factors (Mannello and Tonti, 2007). Despite the widespread standard use of animal
* W8 b+ B. {+ R! isera for in vitro cell culture (Freshney, 2000), there are several problems which exist $ C' T4 T$ v) A: j9 g3 V
relative to its use for clinical application. ; e; @0 U5 q5 {3 z' y- j7 z" X
One of the central issues regarding limitations in using animal sera for clinical cell 1 O6 F9 S( ~* B* g
therapy protocols is that its components are highly variable and, in many cases,
: N: ^& K# }& b9 [7 B# V' Nunknown. Though components of sera have identified, it has also been demonstrated # s3 Y$ s+ i5 m+ b, b8 M( V
that consistency between different lots cannot be assured (Price and Gregory, 1982). In ' \6 G5 G, z3 b; P
the context of multipotent stem cells, serum components and concentrations have 7 o' `) ` E+ i ^( h2 q
significant impact on cell survival and proliferative capacity, phenotype, and multipotent
; U8 t$ a" Q5 E! H7 i! m, @) D3 f. opotential (Agata et al., 2009; Sotiropoulou et al., 2006). Additionally, for clinical use, the
9 s f3 \) @5 ^! y* d ?" Vinclusion of xenogeneic serum for cell expansion carries immunological risks associated
$ F8 H% o/ q3 ~, ?with the immunogenicity of serum proteins and the potential of transmission of prion
% L& h1 f, q( _* \diseases and zoonoses (Shahdadfar et al., 2005). These concerns have led to efforts
?0 E0 h4 l0 N/ |$ Yaimed at incorporating FBS alternatives in cell expansion protocols, including the use of
: Z, j! Y" _# jautologous and allogeneic sera, and the proprietary manufacturing of serum-free media
7 m. h! Y9 |7 V2 j4 `formulations by different companies (Nakamura et al., 2008). Even with these approaches,
4 J, y1 a0 J7 K8 S' _6 m5 Q; x there are limitations in the availability of both autologous and allogeneic
# w# @& q4 `9 V4 U! {sera and companies do not freely disclose their proprietary “serum-free” media
1 Q2 c) U* K' m( E( H" N9 Rcomponents. These factors not only prohibit clinical translation, but also limit @. ?* t- L1 l% f' l _3 M8 `, T& F
widespread use and study of more basic fundamental questions regarding specific
: q. P- |6 R$ C; zmechanisms involved in the modulation of these media on cell function. As such, there
7 b, d# z* b& |4 b3 F, \; s. @exists a need for the development of chemically-defined media which can propagate the
3 K, F; u& Z: o$ [* kcultivation of stem cells without adversely affecting cell function and phenotype
U% X" ^# a& |0 a(Mannello and Tonti, 2007).
. g4 {6 |0 n$ z sIn this study, we aimed to develop a serum-free media (K-M) for the expansion o, Z7 h7 W+ Q2 F: I* v
dental-derived stem cells, including stem cells-derived from exfoliated deciduous (baby)
1 U1 y# K+ G; gteeth (SHEDs) and periodontal ligament stems cells (PDLSCs). Cell expansion in this
3 o3 M. b- n! }( V: ]9 H* mmedia was compared to standard FBS containing media used to culture these cells, # |5 u6 I. z8 G3 T7 p4 X7 f
as well as three other serum-free media formulations (two of which are commercially available)
) k$ _+ V. M1 `* Mused for culture of mesenchymal stem cells. Additionally, through
& s! }# v8 q2 h% Bdifferentiation assays and microarray analyses, multipotency and differential gene
x3 }" q4 E* k1 Bexpression of 84 stem cell associated genes was examined between cells cultured in K-6 C& g# }/ I2 G* X
M vs. those cultured in FBS- containing media. |
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发表于 2011-3-20 08:21
/ J2 A7 y2 i# H+ v% v
，脑子里也没有独家生产这个概念
，所以没理解。