Clinical characteristics and outcome of isolated extramedullary relapse in acute leukemia after allogeneic stem cell transplantation: a single-center analysis.

Isolated extramedullary relapse (EMR) of acute leukemia (AL) is a rare occurrence. However, it appears to be more common after allogeneic stem cell transplantation (allo-SCT). To characterize what has been observed in isolated EMR, we investigated 287 consecutive AL patients (144 acute myeloid leukemia; 138 acute lymphocytic leukemia; 5 acute mixed-lineage leukemia) who underwent allo-SCT. Twelve cases experienced relapse at extramedullary sites without concomitant involvement of the bone marrow (BM). The onset to relapse after allo-SCT was longer in extramedullary sites than in the BM (median, 10 months versus 5.5 months). EMR sites varied widely and included the central nervous system, skin, bone, pelvis and breasts. Univariate analysis demonstrated that cytogenetic abnormalities were correlated significantly with the onset of isolated EMR (P=0.001). The prognosis for patients who develop EMR remained poor but was relatively better than that after BM relapse (overall survival, 10 versus 18 months). Compared with local or single therapy, patients treated with systemic treatment in combination with local treatment could yield a favorable prognosis. In conclusion, we observed a significant number of isolated cases of EMR in AL patients after allo-SCT, cytogenetic abnormalities were correlated significantly with the onset of isolated EMR. We found that intensive approaches combining local and systemic therapy could produce favorable responses which may cure a proportion of these patients.

Citrin/mitochondrial glycerol-3-phosphate dehydrogenase double knock-out mice recapitulate features of human citrin deficiency.

Citrin is the liver-type mitochondrial aspartate-glutamate carrier that participates in urea, protein, and nucleotide biosynthetic pathways by supplying aspartate from mitochondria to the cytosol. Citrin also plays a role in transporting cytosolic NADH reducing equivalents into mitochondria as a component of the malate-aspartate shuttle. In humans, loss-of-function mutations in the SLC25A13 gene encoding citrin cause both adult-onset type II citrullinemia and neonatal intrahepatic cholestasis, collectively referred to as human citrin deficiency. Citrin knock-out mice fail to display features of human citrin deficiency. Based on the hypothesis that an enhanced glycerol phosphate shuttle activity may be compensating for the loss of citrin function in the mouse, we have generated mice with a combined disruption of the genes for citrin and mitochondrial glycerol 3-phosphate dehydrogenase. The resulting double knock-out mice demonstrated citrullinemia, hyperammonemia that was further elevated by oral sucrose administration, hypoglycemia, and a fatty liver, all features of human citrin deficiency. An increased hepatic lactate/pyruvate ratio in the double knock-out mice compared with controls was also further elevated by the oral sucrose administration, suggesting that an altered cytosolic NADH/NAD(+) ratio is closely associated with the hyperammonemia observed. Microarray analyses identified over 100 genes that were differentially expressed in the double knock-out mice compared with wild-type controls, revealing genes potentially involved in compensatory or downstream effects of the combined mutations. Together, our data indicate that the more severe phenotype present in the citrin/mitochondrial glycerol-3-phosphate dehydrogenase double knock-out mice represents a more accurate model of human citrin deficiency than citrin knock-out mice.

[Evaluation of interferon-gamma producing-cells using enzyme linked immunospot assay in mice model of acute graft versus host disease].

OBJECTIVE: To investigate IFN-gamma producing-cells (IFN-gamma PCs) in allogeneic mixed lymphocyte reaction (MLR) and acute graft versus host disease (aGVHD) model of mice. METHODS: Enzyme linked immunospot assay (ELISPOT) was applied to study IFN-gamma PCs in MHC mismatched mice spleen cell MLR and aGVHD model of mice. RESULT: IFN-gamma PCs increased significantly in MLR after allogeneic mice spleen cell stimulation. In the experimental mice aGVHD model, IFN-gamma PCs were significantly higher in the severe aGVHD group than those in the moderate aGVHD. In the moderate aGVHD group, mice with GVHD prophylaxis regimen demonstrated significantly lower level of IFN-gamma PCs, compared with those without prophylaxis. IFN-gamma PCs were significantly correlated with the GVHD clinical scores in the group with moderate aGVHD and prophylaxis regimen. CONCLUSION: ELISPOT is a fast, sensitive and specific approach to evaluate alloresponse in allogeneic mice MLR and IFN-gamma PCs are correlated closely with the severity of aGVHD and prophylaxis regimen in the MHC-mismatched mice model.

[Relationship between the IFN-gamma producing cells specific for recipient and acute graft versus host disease].

OBJECTIVE: To study the relationship between the IFN-gamma producing cell specific for recipient (IFN-gamma-PCSR) in allogeneic stem cell transplantation (allo-HSCT) and acute graft versus host disease (aGVHD). METHODS: In 37 consecutive HLA-identical sibling allo-HSCT pairs, peripheral blood mononuclear cells (PBMNC) from donors before allo-HSCT and recipients after allo-HSCT were taken as responder cells (RC), and PBMNC from recipients before allo-HSCT as allogeneic stimulator cells (allo-SC) in mixed lymphocyte reaction (MLR). IFN-gamma-PCSR in PBMNC were assayed using enzyme linked immunospot assay (ELISPOT). RESULTS: Pretransplantation frequencies of IFN-gamma-PCSR in donor PBMNC were significantly higher in aGVHD group than in non-aGVHD group (P < 0.01) and IFN-gamma PCSRs (>or= 20/2 x 10(5)RC) were significantly associated with the occurrence of grade II-IV GVHD (P < 0.05). Compared with that before allo-HSCT, IFN-gamma PCSR in PBMNC of aGVHD patients was significantly increased (P < 0.05). When PBMNC from aGVHD patients reacted with donor PBMNC, the IFN-gamma PC was significantly lower than that with recipient PBMNC before allo-HSCT. Longitudinal analysis of IFN-gamma PCSR following allo-HSCT showed that compared with that in patients without aGVHD, the IFN-gamma PCSR were significantly higher in patients with that in aGVHD on day +14 (P < 0.01) and day +28 (P < 0.01), respectively. After immunosuppressive therapy for 7 days, IFN-gamma PC declined significantly (P < 0.05). CONCLUSION: The recipient-specific IFN-gamma PC is closely correlated with the allo-response during allo-HSCT and may be helpful for the prediction, diagnosis and monitoring of aGVHD.

[Study on unrelated donor allogeneic bone marrow transplantation with Bu-CY2 conditioning regimen for myelodysplastic syndrome].

OBJECTIVE: To evaluate the efficacy and safety of Bu-CY(2) conditioning regimen on allogeneic bone marrow transplantation (BMT) with unrelated donor for myelodysplastic syndrome. METHODS: Six patients received chemotherapy regimen of busulfan (Bu) and cyclophosphamide (CY) before allogeneic BMT (Bu 4 mg . kg(-1) . d(-1), -7 d - -4 d, CY 60 mg . kg(-1) . d(-1), -3 d - -2 d). Mycophenolate mofetil combined with cyclosporin A and methotrexate was used for prevention of acute graft-versus-host disease after transplantation. Lipo prostaglandin E(1)was used in prophylactic regimen for hepatic veno-occlusive disease. RESULT: Neutrophil count began to be higher than 0.5 x 10(9)/Lat the 18th day after BMT. Platelet count began to be higher than 20 x 10(9)/Lat the 21st day after BMT. Disease-free survival in the six patients was 27 months. CONCLUSION: Bu-CY(2) conditioning regimen on allogeneic bone marrow transplantation with unrelated donor is an effective therapy for patients with myelodysplastic syndrome.

[Detection, enrichment and expansion of T lymphocytes mediating alloresponse based on cytokine].

OBJECTIVE: To detect, enrich and expand the cytokine secreting T lymphocytes after allogeneic PBMNCs stimulation. METHODS: The novel cytokine secretion assay (CKSA) was applied to detect T lymphocytes secreting IFN-gamma at single cell level in human mixed lymphocytes reaction. IFN-gamma secreting T cells were enriched by means of magnetic sorting system and expanded with OKT(3), anti-CD(3)mAb and IL-2 combination. Antigen specificity of the expanded cells was confirmed using enzyme linked immunospot assay. RESULTS: A sizable proportion of IFN-gamma secreting T lymphocytes could be detected [(1.12 +/-0.13)% compared with (0.23 +/-0.07)%] and be further enriched to (67.3 +/-10.5)%, or (93.8 +/-22.1) fold. T lymphocytes could be expanded up to 600-fold within 21-28 days and the specific IFN-gamma response of expanded cells was confirmed with stimulation of the relevant allogeneic PBMNC, which was significantly higher than the irrelevant PBMNC control. CONCLUSION: It is feasible to detect significantly increased IFN-gamma secreting T lymphocytes after allogeneic PBMNCs stimulation based on the CKSA technique at single cell level and these cells can be efficiently enriched and expanded for further research.

[Tandem autotransplants of peripheral blood stem cells following sequential high-dose CHOEP chemotherapy for aggressive lymphoma].

The purpose of this study was to evaluate the effecacy and safety of CHOEP mobilization regimen, and the effect and tolerance of sequential chemotherapy combined with tandem autotransplants of peripheral blood stem cells for aggressive lymphoma. The clinical data of 5 patients with recurrent, aggressive lymphoma treated with of sequential chemotherapy combined with tandem autotransplants were analyzed retrospectively. The patients included 1 HD and 4 NHL. Mobilization regimen was CHOEP combined with G-CSF 5 microg/(kg x d). The conditioning regimen for the tandem transplantation was high-dose CHOEP. The interval of the tandem autotransplantation was 9 (5 - 31) weeks. In tandem autotransplant, the cell number of MNC transfused was 3.05 (1.91 - 4.14) x 10(8)/kg and 3.55 (2.23 - 6.0) x 10(8)/kg; CD34(+) cells were 4.11 (2.59 - 4.94) x 10(6)/kg and 5.70 (2.77 - 10.6) x 10(6)/kg; CFU-GM was 2.96 (2.01 - 4.54) x 10(5)/kg and 2.44 (1.78 - 2.9) x 10(5)/kg respectively (P > 0.05). The results showed that all patients gained prompt and sustained hemotopoietic reconstitution. The interval of ANC >or= 0.5 x 10(9)/L was 10 (8 - 12) days and 10.5 (9 - 12) days; Pt >or= 2.0 x 10(9)/L was 11 (10 - 14) days and 12.5 (10 - 15) days respectively (P > 0.05). Four patients survived, three patients among them were alive in disease-free for median of 46 (9 - 88) months. The overall survival was 80%, and the disease-free survival was 60%. In conclusion, the method of sequential high-dose CHOEP chemotherapy combined with autotransplants of peripheral blood stem cells in tandem for aggressive lymphoma is probably safe and effective.

[Detection and purification of cytokine secreting T lymphocytes in allogeneic reaction and a preliminary study on its clinical significance].

OBJECTIVE: Detection of cytokine secreting T lymphocytes after allogeneic peripheral blood mononuclear cell (PBMNC) stimulation was carried out and its clinical significance discussed so as to explore a new approach to study allogeneic reactive T lymphocytes. METHODS: Cytokine secretion assay (CKSA) was applied to detect T lymphocytes secreting interferon gamma (IFNgamma), interleukin-4 (IL-4) and IL-10 at single cell level in human mixed lymphocytes reaction. T cells secreting IFNgamma from PBMNC were detected in patients with acute graft versus host disease (aGVHD). RESULTS: In comparison with T cells secreting IL-4 and IL-10 which were (0.12 +/- 0.03)% and (0.10 +/- 0.03)%, respectively, a sizable proportion of T cells secreting IFNgamma could be detected (1.12 +/- 0.13)%. Preliminary result indicated that frequency of T cells secreting IFNgamma correlated with the occurrence of aGVHD. CONCLUSIONS: It is feasible to detect T lymphocytes secreting IFNgamma after allogeneic PBMNC and to apply CKSA technique for clinical research.

TGF-beta1 treated murine dendritic cells are maturation resistant and down-regulate Toll-like receptor 4 expression.

OBJECTIVE: To explore the effects of transforming growth factor beta1 (TGF-beta1) on dendritic cells (DC). METHODS: Murine bone marrow cells were cultured with GM-CSF and TGF-beta1 to develop TGF-beta1-treated DC (TGFbeta-DC). Then they were stimulated by lipopolysaccharide (LPS). Their phenotypes were assessed by flow cytometry (FCM). The allogeneic stimulating capacity of DC was measured by mixed lymphocyte reaction (MLR) using BrdU ELISA method and IL-12p70 protein was detected by ELISA. The expression of Toll-like receptor 4 (TLR4) was analyzed by semi quantitative reverse transcriptase-polymerase chain reaction (RT-PCR) and FCM. RESULTS: Compared to immature DC (imDC) cultured by GM-CSF alone, the TGFbeta-DC express lower CD80, CD86, I-Ab and CD40. The TGFbeta-DC were resistant to maturation with LPS. Maturation resistance was evident from a failure to up-regulate co-stimulatory molecules (CMs), to stimulate larger T cells proliferation and to enhance secretion of IL-12p70. We also found that TGF-beta1 could down-regulate TLR4 expression on TGFbeta-DC. CONCLUSION: TGFbeta-DC are resistant to maturation stimulus (LPS) and might have some correlation with the down-modulation of TLR4 expression.

Detection of cytokine-secreting T lymphocytes in allogeneic reaction and a preliminary study on its clinical significance.

In order to explore a new way to study allogeneic reactive T lymphocytes, detection of cytokine-secreting T lymphocytes after allogeneic peripheral blood mononuclear cells (PBMNCs) stimulation and investigation of its clinical significance were performed. A novel cytokine secretion assay (CKSA) was first applied to detect T lymphocytes secreting cytokine including IFN-gamma, IL-4 and IL-10 at single cell level in human mixed lymphocytes reaction. IFN-gamma-secreting T cells from PBMNCs were then evaluated in 2 patients with acute graft versus host disease (aGVHD) after allogeneic bone marrow transplantation. The results showed that compared with IL-4 and IL-10 (which were 0.12 +/- 0.03% and 0.10 +/- 0.03% respectively), a sizable proportion of IFN-gamma-secreting T lymphocytes could be detected (1.12 +/- 0.13)% after allogeneic PBMNCs stimulation. Preliminary results indicated that frequency of IFN-gamma-secreting T lymphocytes correlated with the onset and severity of clinical aGVHD. In conclusion, it is feasible to detect IFN-gamma secreting T lymphocytes after allogeneic PBMNCs stimulation and to apply the CKSA technique for clinical identification of aGVHD.

[A comparison of clinical outcomes between HLA allele matched and 1 - 2 alleles mismatched unrelated allogeneic bone marrow transplantations].

OBJECTIVE: To compare the clinical outcomes between HLA allele matched (HLA-M) and 1 approximately 2 alleles disparity mismatched (HLA-mis) unrelated allogeneic bone marrow transplantation (URD-BMT). METHODS: Thirty-nine patients received HLA-M and 21 received HLA-mis URD-BMT for the treatment of acute leukemia, chronic myeloid leukemia in chronic phase (CP) and myelodysplastic syndromes (MDS) in our hospital between November 1998 and December 2002. Conditioning regimen was Bu 16 mg/kg plus CTX 120 mg/kg, and mycophenolate mofetil (MMF), CsA and MTX were given to prevent aGVHD. RESULTS: Thirty-eight of the HLA-M group and 18 of the HLA-mis group were engrafted successfully. The median follow-up duration was 11 (2.5 - 52.0) months for HLA-M group and 9 (2 - 46) months for HLA-mis group. The 3-year probabilities of disease-free survival (DFS) for HLA-M and HLA-mis group were (79.2 +/- 7.1)% and (45.8 +/- 15.5)%, respectively (P < 0.05). Grade II - IV aGVHD occurred in 10 (26.3%) patients in HLA-M group and 6 (33.3%) in HLA-mis group, respectively (P > 0.05). CONCLUSION: URD-BMT is an effective modality for the treatment of leukemia and MDS. The outcome after URD-BMT can be optimized by matching the HLA-A, B and DR alleles between the donor and recipient.