Survival and Graft versus Host Disease in Murine MHC Mismatched Hematopoietic Stem Cell Transplantation with Co-injection of Mesenchymal Stem Cells / 대한혈액학회지

BACKGROUND: Intravenous injection of mesenchymal and hematopoietic stem cells (MSCs, HSCs) has the disadvantages of low delivery rate to bone marrow and sequestration of cells in the lung and liver. This study was designed to determine whether there is a relationship between the administration route and dosage of stem cells and GVHD and survival. METHODS: MSCs were retrieved from five subcultured C3H/10T1/2, cell lines from C3H/He mice. HSCs were transplanted by injecting 1 x 10(7) of bone marrow mononuclear cells and 5 x 10(6) of spleen cells from six to eight week old female C3H/He mice into six week old irradiated female BALB/c mice. The groups were divided into intravenous injection (IV) and intra-marrow (IM) injection groups. IV and IM+MSC groups consisted of mice transplanted with the same bone marrow mononuclear cells and SP, IV and IM groups, with the additional co-injection of 1 x 10(6) MSCs. RESULTS: Evaluation of all mice, in both groups, showed no difference in GVHD and survival. However, high dose injection with 1 x 10(6) MSCs led to a decreased incidence of GVHD (P<0.05) and improved survival (P<0.01) in both groups. CONCLUSION: The results of this study showed that the positive effects of MSC on GVHD and survival were primarily dependent on the number of injected cells.

CMV antigenemia following pediatric hematopoietic stem cell transplantation:risk factors and outcomes / 소아과

PURPOSE: Cytomegalovirus(CMV) infection still remains as a major cause of morbidity and mortality after stem cell transplantation. In this study, we analyzed the results of antigenemia-guided pre-emptive therapy among children with allogeneic hematopoietic stem cell transplantation to determine the incidence and risk factors associated with CMV antigenemia, and evaluated the efficacy of the CMV antigenemia based preemptive therapy. METHODS: We enrolled 213 pediatric patients following allogeneic hematopoietic stem cell transplantation(HSCT), at the Catholic HSCT center between October 1998 and December 2003. Pre-emptive ganciclovir was started when more than 5 CMV Ag-positive cells were detected in matched sibling HSCT, and when any Ag-positive cells were seen in unrelated allogenic HSCT. RESULTS: CMV antigenemia was observed in 88(41.3 percent) of 213 patients on median day 28(day 11-99). In univariated analysis, use of unrelated donors(other than siblings), age of recipient(more than 5 years at transplant) at transplantation, the presence of recipient CMV-IgG before transplantation, TBI-based conditioning regimen and the presence of acute GvHD(grade > or=II) were the risk factors for positive CMV antigenemia. In multivariate analysis, unrelated bone marrow transplantation, positive recipient CMV serology and acute GvHD(grade > or=II) were the independent risk factors for positive CMV antigenemia. CONCLUSION: Risk factors of CMV infection in children were CMV serostatus of the recipient, the source of stem cells, and acute graft-versus-host disease. The pre-emptive therapy based on CMV antigenemia was effective in the prevention of CMV disease.

Detection of Minimal Residual Disease Using Real-Time Quantitative Polymerase Chain Reaction in Children with Philadelphia Chromosome Positive Acute Lymphoblastic Leukemia / 대한소아혈액종양학회지

PURPOSE: The aim of this study was to detect the bcr-abl/abl mRNA ratio of the patients with Philadelphia chromosome positive childhood acute lymphoblastic leukemia (ALL) after completing chemotherapy or bone marrow transplantation (BMT), by the real-time quantitative polymerase chain reaction (RQ-PCR). It was also to be proved that these quantitative changes of minimal residual disease (MRD) can be used for early detection of relapse and for treatment response. METHODS: The subjectives of this study were 8 patients diagnosed with Philadelphia chromosome positive childhood acute lymphoblastic leukemia (ALL) from January to November in the year 2001. The change of bcr/abl transcript with chemotherapy were evaluated in 6 patients out of them. RESULTS: All of 6 patients reached in hematologically complete remission state by the induction chemotherapy, but the MRD was cytogenetically detected in 5 out of the 6 patients. While the 5 patients were in the hematologically remission state, only 1 patient had the cytogenetical remission after the serial consolidation chemotherapy at the maximum of 6 times. The increased amount of bcr-abl/abl mRNA ratio (up to 10 3) were correlated with the positive real time polymerase chain reaction (RT-PCR) result, but the results of bcr/abl fluorescent in situ hybridization (FISH) were not correlated with the results of RT-PCR and bcr-abl/abl mRNA ratio. The change of bcr/abl transcript was evaluated in 4 patients after BMT. The RT-PCR in 1 month after BMT showed the negative result in all 4 patients in our study. The bcr-abl/abl mRNA ratio in all patients was constantly decreased. However, bcr-abl/abl mRNA ratio in one patient was increased in 6 months after BMT, and the results of second RT-PCR showed positive value, which made the cyclosporine be discontinued immediately. In the 9th month following BMT, the ratio of bcr-abl/abl mRNA was abruptly decreased and the results of second RT-PCR showed the negative value. CONCLUSION: We suggest that RT-PCR or RQ-PCR rather than FISH is more sensitive and effective for detection of MRD. We also observed that Philadelphia chromosome positive childhood ALL could be cured with the BMT, not with the chemotherapy alone, by monitoring MRD.