POSTER ABSTRACTS - ISAKOS

E-poster w/ Standard #766
Meniscal Repair Using Bone Marrow-derived
Mesenchymal Stem Cells: Experimental Study
Using Green Fluorescent Protein Transgenic
Rat
Yasunori Izuta, Hiroshima, JAPAN, Presenter
Mitsuo Ochi, Hiroshima, Hiroshima JAPAN
Nobuo Adachi, Hiroshima, Hiroshima JAPAN
Masataka Deie, Hiroshima, Hiroshima JAPAN
Takuma Yamasaki, Hiroshima, Hiroshima JAPAN
Rikuo Shinomiya, Hiroshima, Hiroshima JAPAN
Hiroshima University, Hiroshima, JAPAN
PURPOSE: The purpose of this study was to
evaluate the efficacy of mesenchymal stem cell
transplantation for meniscal repair in avascular
status using an organ culture model. The cellular
origin of the repaired tissue was also investigated
using mesenchymal stem cells from green
fluorescent protein transgenic (GFP) rats.
METHOD: Mesenchymal stem cells from bone
marrow of GFP rats were isolated and expanded in
monolayer culture. A full-thickness circular defect,
1.2mm in diameter, penetrating vertically on the
anterior portion of the lateral and medial menisci
of Sprague-Dawley rat was produced. The
meniscal defects were treated in one of the
following three ways: in the M group, the defect
was filled with 1.0×106 cells/ml of mesenchymal
stem cell in fibrin glue, in the F group, the defect
was filled with fibrin glue without cells, and in the
C group, the defect was left empty without cells
and fibrin glue. Each of the meniscal explant was
placed in a tissue culture plate and cultured. After
culturing the explants for 2, 4, 12 weeks, 8
explants at every time point were examined
histologically. A fluorescent microscope was used
to detect the GFP positive cells derived from the
donor cells in the repaired tissues.
RESULTS: In the M group, transplanted
mesenchymal stem cells could survive and
proliferate in the meniscal defect in the organ
culture model. After 4 weeks of culture, round cell
proliferation was found in the fibrin glue with new
production of extracellular matrix around the
cells. After 12 weeks of culture, the reparative
tissue with many round cells surrounded by
abundant extracellular matrix stained by toluidine
blue was observed. We could detect the
transplanted GFP cells in the repaired tissue
under a fluorescent microscope after
transplantation. In the C group and F group,
extracellular matrix stained by toluidine blue was
not observed at every time point.
CONCLUSION: This study demonstrated that,
mesenchymal stem cell transplantation can be
used as a novel cell source for the treatment of
meniscal tear in the avascular zone.
E-poster w/ Standard #767
Use of Basic Fibroblast Growth Factor
Combined with a Biodegradable Gelatin
Hydrogel to Enhance Healing of the Avascular
Region of Canine Menisci
Seiji Kubo, Pittsburg, PA, USA, Presenter
Nobuzo Matsui, Kobe, Hyogo, JAPAN
Shinichi Yoshiya, Kobe, Hyogo, JAPAN
Ryosuke Kuroda, Kobe, Hyogo, JAPAN
Takehiko Matsushita, Kobe, Hyogo, JAPAN
Yasuhiko Tabata, Kyoto, Kyoto, JAPAN
Masahiro Kurosaka Kobe Hyogo, JAPAN
Kobe University Graduate School of Medicine,
Kobe, Hyogo, JAPAN
Introduction: Because only the outer third of the
meniscus is vascularized, cartilaginous meniscal
tissue has a limited healing capacity. Although
previous studies have demonstrated that the use
of basic fibroblast growth factor (bFGF) can
facilitate healing process of meniscal tear, it
seems difficult to maintain an effective
concentration of bFGF at the injury site. One
possible measure to overcome this obstacle is to
deliver bFGF in combination with a biodegradable
hydrogel composed of acidic gelatin that forms a
polyion complex with bFGF molecules enabling
gradual release of bFGF over an extended time
period. The purpose of our study was to evaluate
the effect of a bFGF-incorporating gelatin hydrogel
on healing of the defects in the avascular region of
the canine menisci.
Materials and Methods: A full-thickness defect,
two millimeters in diameter, was created in the
avascular region of each canine medial meniscus.
The defects were treated with one of three ways:
Defects were left empty in Group A; filled with
gelatin hydrogels without bFGF in Group B; and
filled with bFGF-incorporating gelatin hydrogels in
Group C. Three defects from each group were
evaluated histologically and biomechanically at 2,
4, 12, and 24 weeks after surgery.
Results: Histology: We observed either no healing
or poor healing with formation of a thin layer of
tissue at the defects in the Group A specimens at
all time points. Week Two: In the Group B,
granulation tissue covered the superficial areas of
the defects, but the gelatin in the deep areas
contained only a few spindle-shaped cells.