RESUMO
INTRODUCTION: This study assessed the effect of mineral trioxide aggregate (MTA) and calcium-enriched mixture (CEM) cement on odontogenic differentiation and mineralization of stem cells. METHODS AND MATERIALS: After confirmation of stemness and homogeneity of stem cells derived from apical papilla (SCAPs) using flow cytometry, the cells were exposed for 3 weeks to either osteogenic medium (OS) or CEM extract+OS (CEM+OS) or MTA extract in OS (MTA+OS) or DMEM based regular culture media (negative control). Relative expression of alkaline phosphatase (ALP), dentine sialophosphoprotein (DSPP), osteocalcin (OSC), and osterix (SP7) were measured at days 14 and 21 using RT-qPCR method. At the same time points Alizarin Red staining method was used to assess mineralization potential of SCAPS. Gene expression changes analysis were made automatically using REST® software and a P<0.05 was considered significant. RESULTS: After 2 weeks of exposure, expression of all genes were between 3 and 52 times the expression of GADPH (all were upregulated except SP7 in the control, P<0.05). After 3 weeks, relative expressions of the genes: ALP, SP7, DSPP, and OSC were respectively 275.9, 528.3, 98.4, and 603.7 times the expression of GADPH in the control group (OS). These were respectively 17.405, 29.2, 11.8, and 6.5 in CEM+OS group, and 163.8, 119.7, 102.5, and 723.9 in MTA+OS group. All of these were confirmed as upregulated (P<0.05) except for ALP and OSC of DM+CEM group. After 2 weeks, alizarin red staining showed similar mineralized nodules in OS, MTA+OS, and CEM+OS. In third week, larger nodules were seen in MTA+OS and OS, but not in CEM+OS. CONCLUSION: After 2 weeks, gene expressions were almost comparable in OS, CEM+OS, and MTA+OS. After 3 weeks, OS and MTA+OS upregulated genes much greater than in 2nd week. However, upregulation in CEM+OS might not increase in 3rd week compared to those in 2nd week.
RESUMO
Augmentation of microchimerism in solid organ transplant recipients by donor bone marrow cells (DBMC) infusion may promote immune hyporesponsiveness and consequently improve long-term allograft survival. Between March 2005 and July 2007, outcomes for 20 living unrelated donor (LURD) primary kidney recipients with concurrent DBMC infusion (an average of 2.19 ± 1.13 x 109 donor cells consisting of 2.66 ± 1.70 x 107 CD34⺠cells) were prospectively compared with 20 non-infused control allograft recipients given similar conventional immunosuppressive regimens. With five years of clinical follow up, a total of 11 cases experienced rejection episodes (3 DBMI patients vs. 8 controls, p = 0.15). One DBMC-infused patient experienced chronic rejection vs. two episodes (1 biopsy-confirmed) in the control patients. Actuarial and death-censored 5-y graft survival was significantly higher in infused patients compared with controls (p = 0.01 and p = 0.03, respectively). Long-term graft survival was significantly associated with pre-transplant anti-HLA antibodies (p = 0.01), slightly with peripheral microchimerism (p = 0.09) and CD4âºCD25âºFoxP3⺠T cells (p = 0.09). Immunosuppressant dosing was lower in infused patients than controls, particularly for mycophenolate mofetil (p = 0.001). The current findings as well as our previous reports on these patients indicates clinical improvement in long-term graft survival of renal transplant patients resulting from low-dose DBMC infusion given without induction therapy.
Assuntos
Aloenxertos/fisiologia , Transplante de Medula Óssea , Rejeição de Enxerto/prevenção & controle , Sobrevivência de Enxerto/imunologia , Transplante de Rim , Estudos de Casos e Controles , Rejeição de Enxerto/imunologia , Humanos , Interleucina-10/genética , Interleucina-10/imunologia , Estudos Prospectivos , Fator de Crescimento Transformador beta1/genética , Fator de Crescimento Transformador beta1/imunologia , Quimeras de Transplante/imunologia , Resultado do Tratamento , Doadores não RelacionadosRESUMO
BACKGROUND: This pilot study aimed to assess whether the perioperative infusion of donor bone marrow cells (DBMC) in renal allograft recipients can affect the appearance of peripheral regulatory T-cell subsets and the profile of cytokine-producing cells [interferon-gamma (IFN-γ), interleukin (IL)-17 and IL-10] 2 years after transplantation. METHODS: Fresh blood samples were collected from 14 kidney recipients who received infusion and from 13 kidney recipients without infusion who served as controls at the end of the second post-transplantation year. Initially the percentages of CD4(+)CD25(+)FoxP3(+) T cells and CD3(+)CD8(+)CD28(-) T cells were quantified using flowcytometry. Thereafter, the frequencies of IL-10-, IL-17- and IFN-γ-producing cells were determined separately using the ELISPOT technique with peptides corresponding to mismatched donor HLA-DR molecules and phytohemagglutinin (PHA). RESULTS: The mean numbers of IFN-γ- and IL-17-producing cells in response to PHA were lower in infused patients than in controls (P = 0.02 and P = 0.18, respectively); however, an increased frequency of IL-10-producing cells was observed compared to controls (P = 0.07). Furthermore, the ratio of IL-10/IFN-γ-producing cells was significantly higher in the DBMC-infused group versus controls (P = 0.01). There was a negative correlation between the percentage of CD3(+)CD8(+)CD28(-)T cells and IL-17-producing cells in the infused group (r = -0.539, P = 0.04). The mean levels and the frequency of microchimerism within the first post-transplantation year were also significantly higher in infused patients than in controls (P = 0.007 and P = 0.001, respectively). CONCLUSION: Our findings suggest that DBMC infusion could partially stimulate the regulatory mechanisms against alloimmune responses in kidney allograft recipients