In Vivo Osteogenesis in Porous Hydroxyapatite Scaffold Processed in Hyaluronic Acid Solution

2007 ◽  
Vol 361-363 ◽  
pp. 1185-1188 ◽  
Author(s):  
Masataka Yoshikawa ◽  
T. Yabuuchi ◽  
N. Tsuji ◽  
Y. Shimomura ◽  
H. Hayashi ◽  
...  

Porous hydroxyapatite (HA) scaffolds were processed in hyaluronic acid solution. Bone marrow cells obtained from the bone shaft of femurs of Fischer 344 rats at 1×106/ml concentration were seeded in pores of the scaffolds. The scaffolds were implanted in the dorsal subcutaneous tissue of rats for 2, 4, 6 or 8 weeks. Removed HA scaffolds at 2 and 4 week after dorsal subcutaneous implantation were histologically examined. At all experimental periods, osteocalcin in the scaffold was immunochemically measured for the quantitative analysis of osteogenesis by bone marrow cells in the porous HA scaffolds. Moreover, value of alkaline phosphatase (ALP) activity in the scaffolds was measured. Osteocalcin measured in scaffolds without bone marrow cells was 1.3 ng in an average and the ALP activity was 62.2 μmol at 4 week. In hyaluronic acid processed scaffold with bone marrow cells, quantity of osteocalcin increased from 1.6 ng at 2 week to 2.2 ng at 4 week after implantation of the scaffold. Histologically, many pores containing bone in the scaffolds immersed in hyaluronic acid solution were detected. Significant difference of the quantity of osteocalcin was recognized between 2 and 4 week implantation. There was no significant difference in the quantity of osteocalcin between the scaffolds implanted for 4 and 8 weeks. Value of ALP activity of the scaffold implanted for 4 weeks showed significant difference comparing with that implanted for 6 and 8 weeks. From the results of this study, quantitative increase of the bone formation in the pores of HA scaffolds would be able to observe from 6 to 8 weeks after implantation on the scaffolds by immersion in hyaluronic acid solution

2005 ◽  
Vol 284-286 ◽  
pp. 651-654
Author(s):  
Jin Iida ◽  
Takafumi Yoshikawa ◽  
Kazuhide Miyazaki ◽  
Noriko Okumura ◽  
Yoshinori Takakura

Osseous tissue can be formed by culturing marrow cells with compounds such as dexamethasone and that a bone matrix cultured in this manner possesses BMP activity. We have reported that artificial bones with a high level of osteogenic potential can be prepared by culturing artificial bone materials with cultured osseous tissue. Here, in an attempt to develop activated cultured bone constructs with even greater osteogenic potential, the effects of the female hormone estriol on osteogenesis were investigated. Bone marrow cells were collected from the femur shafts of 7-week-old male Fischer rats, and subjected to primary and secondary cultures. During secondary culture with or without dexamethasone (Dx), 10-5, 10-6, 10-7, 10-8 or 10-9 M of estriol was added to a standard culture medium containing ascorbic acid and β-glycerophosphosphate. The alkaline phosphatase(ALP) activity and Ca levels were measured and statistically analyzed. There was a significant difference in ALP activity between the control group and the estriol groups, and ALP activity was the highest in the 10-7 and 10-8 M groups, being about 2.5 times higher than in the control group. Similar results were seen for Ca levels. Furthermore, in vivo study showed10-7M-estriol-treated-cultured bone/ceramic construct has significant high osteogenic potential when it is grafted into in vivo. Estriol has been reported to increase bone mass, and the results of the present study suggest that the osteogenic potential of cultured bone constructs can be more than doubled by adjusting the concentration of estriol in bone marrow cell culture. Therefore, the use of estriol may be able to facilitate osteogenesis in bone regeneration therapy.


2009 ◽  
Vol 25 (7) ◽  
pp. 467-471 ◽  
Author(s):  
BN Mojidra ◽  
K. Archana ◽  
AK Gautam ◽  
Y. Verma ◽  
BC Lakkad ◽  
...  

Pan masala is commonly consumed in south-east Asian and other oriental countries as an alternate of tobacco chewing and smoking. Genotoxic potential of pan masala (pan masala plain and pan masala with tobacco known as gutkha) was evaluated employing chromosome aberration (CA) and micronucleus (MN) assay in vivo. Animals were exposed to three different doses (0.5%, 1.5% and 3%) of pan masala plain (PMP) and gutkha (PMT) through feed for a period of 6 months and micronucleus and chromosomal aberrations were studied in the bone marrow cells. Induction of mean micronuclei in polychromatic erythrocytes (MNPCE) and normochromatic erythrocyte (MNNCE) was higher in both types of pan masala treated groups with respect to control group. Both pan masala plain and gutkha treatment significantly induced the frequency of MNPCE and MNNCE in the bone marrow cells, indicating the genotoxic potential. Furthermore, slight decline in the ratio of polychromatic erythrocytes to normochromatic erythrocytes was also noticed, suggesting the cytotoxic potential even though the ratio was statistically non significant. A dose-dependent, significant increase in chromosome aberration was observed in both types of pan masala treated mice with respect to control. However, no significant difference in micronucleus and chromosomal aberration induction was noticed between two types of pan masala exposed (PMP and PMT) groups. Results suggest that both types of pan masala, i.e. plain and gutkha, have genotoxic potential.


Blood ◽  
1996 ◽  
Vol 87 (10) ◽  
pp. 4136-4142 ◽  
Author(s):  
I Kawashima ◽  
ED Zanjani ◽  
G Almaida-Porada ◽  
AW Flake ◽  
H Zeng ◽  
...  

Using in utero transplantation into fetal sheep, we examined the capability of human bone marrow CD34+ cells fractionated based on Kit protein expression to provide long-term in vivo engraftment. Twelve hundred to 5,000 CD34+ Kit-, CD34+ Kit(low), and CD34+ Kit(high) cells were injected into a total of 14 preimmune fetal sheep recipients using the amniotic bubble technique. Six fetuses were killed in utero 1.5 months after bone marrow cell transplantation. Two fetuses receiving CD34+ Kit(low) cells showed signs of engraftment according to analysis of CD45+ cells in their bone marrow cells and karyotype studies of the colonies grown in methylcellulose culture. In contrast, two fetuses receiving CD34+ Kit(high) cells and two fetuses receiving CD34+ Kit- cells failed to show evidence of significant engraftment. Two fetuses were absorbed. A total of six fetuses receiving different cell populations were allowed to proceed to term, and the newborn sheep were serially examined for the presence of chimerism. Again, only the two sheep receiving CD34+ Kit(low) cells exhibited signs of engraftment upon serial examination. Earlier in studies of murine hematopoiesis, we have shown stage-specific changes in Kit expression by the progenitors. The studies of human cells reported here are in agreement with observations in mice, and indicate that human hematopoietic stem cells are enriched in the Kit(low) population.


1984 ◽  
Vol 26 (2) ◽  
pp. 152-157
Author(s):  
S. M. Singh ◽  
D. L. Reimer

Frequency of sister chromatid exchanges (SCE) were recorded separately for different chromosomes from bone marrow cells of female mice of the two genetic strains (C3H/S and C57BL/6J). SCEs were evaluated following different doses of 5-bromo-2′deoxyuridine (BrdU) as nine hourly i.p. injections. The SCE per cell increased with increasing BrdU doses which was slightly higher in C3H/S than in the C57BL/6J. SCEs per cell were variable at every treatment – strain combination, possibly reflecting the heterogeneous nature of the bone marrow cells. In general, there is a positive correlation between SCE per chromosome and the relative chromosome length. Total SCEs on one of the large chromosomes (most likely the X chromosome), however, are significantly higher than expected on the basis of relative length alone. Most of this increase is attributable to one of the homologues of this chromosome, which is not in synchrony with the rest of the chromosomes and may represent the late-replicating X. These results when viewed in the light of replication properties of the heterochromatinized X, suggest a direct involvement of DNA replication in SCE formation and may argue against the replication point as the sole site for the SCEs.Key words: sister chromatid exchange, BrdU, recombination, replication, X chromosome.


Blood ◽  
2013 ◽  
Vol 121 (12) ◽  
pp. e90-e97 ◽  
Author(s):  
Mark Wunderlich ◽  
Benjamin Mizukawa ◽  
Fu-Sheng Chou ◽  
Christina Sexton ◽  
Mahesh Shrestha ◽  
...  

Key Points A relevant xenograft chemotherapy model was developed by using standard AML induction therapy drugs and primary human AML patient samples. Human AML cells show significantly increased sensitivity to in vivo chemotherapy treatment compared with murine LSK and total bone marrow cells.


Blood ◽  
1988 ◽  
Vol 71 (6) ◽  
pp. 1633-1640
Author(s):  
LM Pelus ◽  
PS Gentile

Intravenous (IV) injection of 0.1 to 10 micrograms of authentic prostaglandin E2 (PGE2) in intact steady-state mice induces a population of bone marrow and spleen cells having the capacity to suppress CFU-GM proliferation when admixed with normal bone marrow cells. Equivalent suppression of CFU-GM committed to monocytic as well as granulocytic differentiation was observed using colony-stimulating factors (CSFs) differing in their lineage specificities and by direct morphological analysis of proliferating clones. Kinetic analysis indicates that suppressive bone marrow cells appear within 2 hours after PGE2 injection, are maximal at 6 hours, and are no longer observed by 24 hours postinjection. Positive and negative selection studies using monoclonal antibodies indicate that the PGE2-induced suppressor cells react positively with anti-GMA 1.2, MAC1, and F4/80 monoclonal antibodies, suggesting a myeloid/monocytic origin. As few as 1,000 positively selected bone marrow or spleen cells were able to inhibit maximally normal CFU-GM proliferation by 50,000 control bone marrow cells. Suppression of normal CFU-GM can be substituted for by 24- hour cell-free supernates from unseparated bone marrow cells or GMA 1.2 or F4/80 positively selected marrow or spleen cells from PGE2-treated but not control mice. These supernates also inhibited BFU-E proliferation. Injection of as few as 2 million bone marrow cells from PGE2-treated mice into steady-state mice or animals hematopoietically rebounding following a sublethal injection of cyclophosphamide significantly suppressed total CFU-GM proliferation in recipient mice within 6 hours. In summary, these studies describe the detection of a novel hematopoietic control network induced by PGE2 in intact mice.


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