[Retrospective analysis on therapeutic effect of autologous hematopoietic stem cell transplantation in multiple myeloma patients].

OBJECTIVE: To evaluate the efficacy and prognostic factors of autologous hematopoietic stem cell transplantation (ASCT) in multiple myeloma (MM) patients. METHODS: Retrospective analysis was performed in 27 MM patients undergoing ASCT at our hospital from May 2004 to August 2011. After comparing with 28 patients achieving very good partial response (VGPR) or better outcome and not undergoing ASCT, the impact on the extent of response, progression-free survival (PFS) and overall survival (OS) as well as related prognostic factors of MM patients were analyzed. RESULTS: All patients successfully underwent hematopoietic reconstruction without transplantation-related mortality. The complete remission (CR) rate of ASCT group increased from 25.9% (7/27) at pre-ASCT to 70.4% (19/27) at post-ASCT (P < 0.01). The estimated 5-year rate of progression-free survival was 56.2% (median not reached) in the ASCT group and 24.9% (median 29 months) in the non-ASCT group (P < 0.05). The 5-year probability of overall survival was 52.2% (median not reached) in the ASCT group and 33.1% (median 60 months) in the non-ASCT group (P > 0.05). Univariate analysis in ASCT group demonstrated that maintenance/consolidation therapy was associated with PFS (P = 0.010) and OS (P = 0.008).Patients on induction therapy containing bortezomib and early ASCT maintenance therapy all survived without disease progression until final follow-up (P = 0.010). CONCLUSIONS: ASCT can further increase the CR rate, prolong PFS and probably OS. The incorporation of novel agents into induction, consolidation and maintenance phases has optimized the anti-myeloma activity of ASCT and may be important for improved long-term outcomes.

[The incidence of TET2 gene mutation and its clinical significance in acute myeloid leukemia patients].

OBJECTIVE: To evaluate the prevalence of TET2 gene mutation in acute myeloid leukemia (AML) patients, and analyze their clinical characteristics and prognosis. METHODS: Polymerase chain reaction (PCR) and direct sequencing were used to sequence exon 3 to 11 of TET2 gene. RESULTS: Among 96 AML patients, TET2 gene mutation was detected in 13 (13.54%) patients (95%CI 6.70% - 20.38%). The median age was 54 years in mutated group and 41 years in unmutated group (P = 0.010). Mutated and unmutated patients did not significantly differ in gender, white blood cells (WBC) count at diagnosis, platelet count, PB and BM blast percentage and chromosome karyotype, excepting for hemoglobin level 84 (70 - 108) g/L in mutated group versus 70 (55 - 87) g/L in unmutated group (P = 0.032). TET2 gene mutation had no significant correlation with C-KIT, FLT3, JAK2V617F mutations, but did with NPM1 mutation. TET2 mutated patients had lower CR1 rate and 2-year overall survival than unmutated in non-M(3) patients (P < 0.05). CONCLUSIONS: TET2 gene mutation is more prevalent in older AML patients and has a certain correlation with clinical characteristics and outcome. It may be a molecular marker for poor prognosis in AML.

[Correlation between clinical outcome and WT1 detection after hematopoietic stem cell transplantation in acute leukemia].

OBJECTIVE: To evaluate preliminarily the significance of detecting the Wilms' tumor (WT1) gene level on monitoring minimal residual disease (MRD) and predicting the clinical outcome in patients of acute leukemia following hematopoietic stem cell transplantation (HSCT). METHODS: The mRNA expression levels of WT1 and house-keeping gene ABL were dynamically measured with Real-time quantitative reverse transcription polymerase chain reaction (RQ-RT-PCR) on 326 bone marrow samples from 63 post-HSCT patients in our hospital from December 2001 to September 2009. After comparing the WT1 levels of patients with different post-transplantation outcomes, the investigators used the receiver operating characteristic (ROC) curve to determine the WT1 threshold so as to predict their clinical relapses. Then different prognoses of WT1 positive and negative patients were analyzed. RESULTS: The levels of WT1 expression showed significant difference between the 19 relapsing and 44 non-relapsing patients with the median expression levels of 1270 (55 - 47 596) and 132 (0 - 2959) respectively (P < 0.01). In 19 relapsing patients, except for 1 patient discontinuing the detection of WT1, 10 mortality cases due to recurrence had higher levels of WT1 expression than other 8 patients (P > 0.05). According to the ROC curve, the cut-off value of WT1 at 585 could separate 63 patients into the WT1-positive group (> 585) and the WT1-negative group (≤ 585). The WT1-negative group was found to have a longer relapse-free survival (RFS) and overall survival (OS) than the positive group (all P < 0.01). Twenty-one WT1-positive patients were followed up for 3, 4 - 6, 7 - 9 and 9 months respectively. The cumulative post-HSCT recurrence rates in those WT1-positive cases were 8/8, 2/4, 2/4 and 3/5 (P = 0.063) respectively. And the intervention was ineffective. CONCLUSION: WTl gene may be an independent factor of monitoring MRD. And WT1 > 585 is a poor post-HSCT prognostic factor for the patients of acute leukemia.

[The role of intracellular signal pathway of mTOR/S6 in CD3+ T lymphocytes of refractory/relapsed aplastic anemia patients].

OBJECTIVE: To explore the activation status of signal pathway of mTOR/S6 in bone marrow (BM) T lymphocytes of refractory/relapsed aplastic anemia patients (AA), and the effects of rapamycin (RAPA) and CTLA-4 immunoglobulin (CTLA-4Ig) on this pathway. METHODS: BM was collected from 13 refractory/relapsed AA patients, 8 newly diagnosed severe AA (SAA) patients and 10 iron deficiency anemia (IDA) (as controls) patients, and cocultured with RAPA and CTLA-4 Ig. The expression of p-mTOR, p-S6 and Interferon gamma (IFN-gamma) in CD3(+)T cells was measured by flow cytometry (FCM). RESULTS: (1) The expression of p-mTOR, p-S6 and IFN-gamma in CD3(+)T cells in refractory/relapsed AA group were significantly higher than those in controls (P < 0.01). (2) The expression of p-mTOR and p-S6 in T cells in newly diagnosed SAA group, was similar to those in controls (P > 0.05), but significantly lower than those in refractory/relapsed AA group (P < 0.01). The expression level of IFN-gamma in T cells were significantly higher than that in controls (P < 0.01). (3) On exposure to RAPA, the levels of p-mTOR, p-S6 and IFN-gamma in T cells in refractory/relapsed AA patients were significantly lower than those before the exposure (all P < 0.05). And so were when exposed to CTLA-4 Ig (all P < 0.01). CONCLUSION: (1) The mTOR/S6 signal pathway is activated in refractory/relapsed AA. (2) The expression of p-mTOR, p-S6 and IFN-gamma in refractory/relapsed AA can be suppressed by RAPA or CTLA-4Ig. (3) The signal pathway of CD28/mTOR/S6/IFN-gamma might take part in immune pathogenesis of refractory/relapsed AA.

[5-azacytidine treatment induces tumor suppressor gene XAF1 expression and inhibits proliferation in myeloma cells].

OBJECTIVE: To investigate the effect of 5-azacytidine on XAF1 expression in myeloma cell lines RPMI8226 and XG-7 and the in vitro anti-myeloma activity of 5-azacytidine. METHODS: XAF1 mRNA and protein expression was detected by semi-quantitative reverse transcriptase PCR and Western blot, respectively. Methylation specific PCR (MSP) was used to detect methylation status of XAF1 promoter CpG islands. RPMI8226 and XG-7 cells were treated with 0-5 micromol/L of 5-azacytidine and Cell Counting Kit-8 colorimetric assay was used to evaluate the growth inhibitory effect. Cell apoptosis was determined with Annexin V-PE/7-AAD staining by flow cytometry. RESULTS: Untreated RPMI8226 cells expressed XAF1 mRNA isoforms 1 and 2, and untreated XG-7 cells had no XAF1 expression. Hypermethylation of XAF1 promoter CpG islands was detected in both the cell lines. After treated with 2.5 micromol/L 5-azacytidine for 72 h, both the cell lines expressed full-length XAF1 transcript and protein. 5-azacytidine treatment led to XAF1 promoter CpG islands hypomethylation and showed anti-myeloma activity in a time- and concentration-dependent manner with IC50 of 2.4 micromol/L and 2.6 micromol/L at 48 h for RPMI8226 and XG-7 cell lines, respectively. CONCLUSIONS: Lack of XAF1 expression and abnormal expression of XAF1 in myeloma cell lines are associated with XAF1 gene promoter CpG islands hypermethylation. 5-azacytidine treatment can induce XAF1 mRNA and protein expression and exerts anti-myeloma activity via apoptosis at clinically achievable concentrations.

[A comparison of clinical outcomes between unrelated donor and HLA-haploidentical donor hematopoietic stem cell transplantation].

OBJECTIVE: To compare the clinical outcomes between unrelated donor hematopoietic stem cell transplantation (URD-HSCT) and HLA-haploidentical (Hi)-HSCT. METHODS: Twenty-five patients with hematologic malignancies received URD-HSCT and thirty patients received Hi-HSCT. The conditioning regimen consisted of modified BUCY or modified total body irradiation (TBI) plus CY. Acute graft-versus-host disease (aGVHD) prophylaxis consisted of cyclosporin ( CsA), short-term methotrexate (MTX), mycophenolate mofetil (MMF), or the combination of CsA, MTX and MMF plus antithymocyte globulin (ATG) or antilymphocyte globulin (ALG), or the combination of CsA, MTX, MMF, ATG/ ALG and CD25 monoclonal antibody. RESULTS: All patients in the URD-HSCT group and 29 patients in the Hi-HSCT group were engrafted successfully. The median follow-up duration was 7 (2 -59) months for URD-HSCT group and 7.3 (1 - 35) months for Hi-HSCT group. The 3-year probabilities of disease-free survival (DFS) for URD-HSCT and Hi-HSCT group were (54.1 +/- 11.9)% and (43.1 +/- 9.1)%, respectively (P =0.13). Grade III - IV aGVHD occurred in 10 patients in URD-HSCT group and 11 in Hi-HSCT group (the cumulative incidence 40.0% vs 37.9%, P > 0.05), respectively. Ten patients (40.0%) died of transplantation-related mortality (TRM) in URD-HSCT group and 17 (56.7%) in Hi-HSCT group (P >0. 5). Two patients relapsed in each group (the rate of relapse 8.0% vs 6.0%, P >0.05). The primary causes of death included severe aGVHD with infection,severe pulmonary infection and relapse. CONCLUSION: Both URD-HSCT and Hi-HSCT are effective and curable treatment for refractory or high-risk hematologic malignancies. The optimal donor should be chose individually. The severe aGVHD and consequent infection are still the main cause of TRM.

[Prevalence and clinical significance of FLT3 mutations in acute promyelocytic leukemia].

OBJECTIVE: To evaluate the prevalence of Fms-Like tyrosine kinase 3 (FLT3) mutations including internal tandem duplication (ITD) of juxtamembrane region and point mutation in the second tyrosine kinase domain (TKD) in acute promyelocytic leukemia (APL) and its clinical significance. METHODS: Bone marrow mononuclear cells from 160 newly diagnosed APL patients were analyzed. Polymerase chain reaction (PCR) was used to detect FLT3-ITD mutations, FLT3-ITD positive samples were further analyzed for the ITD allelic ratio (ITD-AR, mutant-wild type ratio). The FLT3-TKD mutation was analyzed by PCR amplification of exon 20 followed by EcoR V digestion and sequencing. RESULTS: Out of 160 patients, 30 (18.75%) patients were FLT3-ITD positive, 17 (10.62%) were FLT3-TKD positive, 2 had both of mutations. The initial WBC count and the ratio of short type PML-RAR alpha isoforms in FLT3-ITD positive and FLT3-TKD positive patients were all higher than that in patients with wild-type FLT3 (FLT3-wt) (P < 0.05). For FLT3-ITD positive patients, the incidences of retinoic acid syndrome (RAS) and disseminated intravascular coagulation (DIC) were 41.7% and 65.4%, respectively, being higher than that of FLT3-wt patients, while their complete remission (CR) rate was lower (69.2% vs 90.3%, P < 0.05). For FLT3-TKD positive patients, the incidence of RAS, DIC and CR rate were not significantly different from that of FLT3-wt patients (P > 0.05). FLT3-ITD positive patients had a shorter overall survival (OS) (P < 0.05), but not disease-free survival (DFS) (P > 0.05) as compared with FLT3-wt patients. There was no significant difference in either OS or DFS between FLT3-TKD positive and FLT3-wt patients. The ITD-AR of 30 FLT3-ITD positive patients varied from 0.11 to 6.55 with a median of 1.0. The initial WBC count, incidence of RAS and DIC, CR rate were not significantly different between the patients with ITD-AR greater than 1.0 and lower than 1.0 (P > 0.05). CONCLUSIONS: FLT3 mutations (FLT3-ITD or FLT3-TKD) are frequently identified in patients with newly diagnosed APL, both mutations are associated with higher initial WBC and short type PML-RAR alpha isoforms. FLT3-ITD mutation is more frequent than FLT3-TKD mutation, and predicts a poorer prognosis, whereas FLT3-TKD mutation does not show the same unfavorable prognostic effect on APL patients.

[Study on relationship between pretransplantation host thymic recent output function and prognosis in HLA-matched sibling hematopoietic stem cell transplantation].

OBJECTIVE: To study the relationship between pretransplantation host thymic recent output function and prognosis in HLA-matched sibling bone marrow transplantation (MSD-BMT) and determine whether pretransplantation host thymic recent output function can act as a marker for predication of prognosis after HSCT. METHODS: T-cell receptor excision circle (TREC) in DNA of pretransplantation peripheral blood mononuclear cells from 64 patients underwent MSD-BMT was detected by real-time quantitative PCR. The content of TREC in 70 normal donors was detected as well. All clinical data of patients after HSCT were collected and studied. Survival rates of patients after HSCT were estimated with Log-rank test. Univariate and multivariate analysis of prognostic factors were carried out by COX's proportional hazard regression model. RESULTS: The mean value of TREC in normal donors was (3351 +/- 3711) copies/10(5) cells. There was an inverse correlation between TREC and age in the donor groups. Before transplantation, all patients were detected TREC, with a mean TREC number of (180 +/-332) copies/10(5) cells being significantly lower than that of normal donors. The results of univariate analysis showed that the counts of pre-HSCT TREC were closely, correlated with long term survival and chronic graft versus host disease (cGVHD) (P < 0.05) and with CMV infection (P = 0.084) but not with acute graft versus host disease (aGVHD). The results of multivariate analysis showed the same thing as that of univariate analysis. CONCLUSION: Pretransplantation host thymic recent output function is closely correlated with prognosis in MSD-BMT and can be a factor for predicting the outcome of HSCT.

[Prediction of T-cell immune reconstitution by investigating T cell receptor excision circle and T-cell receptor beta-chain variable region clonal repertoire in leukemia patients after allogeneic hematopoietic stem cell transplantation].

OBJECTIVE: To predict T-cell immune reconstitution by investigating T cell receptor excision circles (TREC) and T-cell receptor beta-chain variable region (TCRBV) clonal repertoire in leukemia patients after allogeneic hematopoietic stem cell transplantation (allo-HSCT). METHODS: Real-time quantitative PCR was used to detect the TREC in 43 leukemia patients undergoing matched sibling donor bone marrow transplantation (MSD BMT), matched unrelated donor (MUD) BMT, or haploidentical-stem cell transplantation (HID-SCT), and in 70 normal individuals. RT-PCR was used to amplify 24 subfamily genes of T-cell receptor beta-chain variable region (TCRBV) in 24 of the 43 patients and 5 normal donors as control. The PCR products were further analyzed by genescane to evaluate the clonality of BV subfamily, characteristics of complementarity determining region 3 (CDR3), and the usage rate in BV subfamily. RESULTS: There were (335.1 +/- 782.5) copies/10(5) cells in the 43 patients before transplantation, far lower than the normal value. The TREC values of the patients of the 3 groups all decreased obviously 3 months after transplantation. The TREC value of the MSD-BMT group recovered faster than the other two groups and reached the value before transplantation in 24 months. The recovery of TREC value in the HID-BMT group was delayed. 3 - 19 months after transplantation, the usage of TCRBV subfamilies was still restricted. There were 6 - 16 BV subfamilies expressed and 33% - 48% of them were polyclonals, the others were monoclones and oligoclones and existed in 24 BV subfamilies, no common monoclone BV subfamilies was expressed. CONCLUSION: Investigation of the TREC and TCRBV clonal repertoire showed that the number of naive T cell is lower and the usage of TCRBV subfamilies skewed 3 - 24 months after allo-HSCT. The immune deficiency of the patients undergoing HID-BMT is more prominent and consistent with the clinical process.

[Preliminary study of the effect of HLA-Cw on haploidentical hematopoietic stem cell transplantation].

OBJECTIVE: To investigate the effect of HLA-Cw on haploidentical hematopoietic stem cell transplantation (HHSCT) without T-cell depletion. METHODS: HLA-Cw were detected with PCR-SSP, the clinical data of 21 cases of haploidentical hematopoietic stem cell transplantation, including 8 standard risk and 13 high risk cases from July 2002 to March 2006 were summarized, and the effect of HLA-Cw in HHSCT was analyzed. RESULTS: Twenty patients achieved sustained, full-donor-type engraftment. The HLA-Cw matched and mismatched groups attained neutrophil recovery at a median of 12 days and 13 days, and platelet recovery to more than 20 x 10(9)/L at a median of 20 days and 23 days respectively (P > 0.05). The cumulative incidences of grades II-IV acute GVHD were 76.9% in HLA-Cw matched group and 14.3% in the mismatched group(P < 0.05). The incidences of chronic GVHD were 85.7% in HLA-Cw matched group and 57.1% in the mismatched group(P > 0.05). The 28 months disease-free survival probabilities were 49.0% in HLA-Cw matched group, and 85.7% in the mismatched group (P > 0.05). The Karnofsky score of survival patients was over 90%. CONCLUSION: HLA-Cw mismatched in donor and recipient of HHSCT is beneficial for reducing II-IV aGVHD, and being in favor of long term survival.

[Analysis of NPM1 gene mutations in acute myeloid leukemia].

OBJECTIVE: To evaluate the prevalence of nucleophosmin (NPM1) gene exon 12 mutations in adults with acute myeloid leukemia (AML) and its clinical characteristics. METHODS: Genomic DNAs from 101 AML adults were screened by PCR and sequencing or capillary electrophoresis (CE) for NPMI mutations. RESULTS: NPM1 exon 12 mutations were present in 31.7% of the overall cohort, including 1/1 (100%) of M0, 9/17(52.9%) of M1 , 7/25 (28.0%) of M2, 0/23(0%) of M3, 2/7 (28.6%) of M4 and 13/25 (52.0% ) of M5. NPM1 gene mutations were more prevalent in patients with normal karyotype (27/59, 45.8%) compared with that in those with karyotypic abnormalities (5/42, 11.9% ) (P < 0.001). NPM1 mutant cases were significantly associated with old age (P < 0.05), high peripheral white cell count (P < 0.05) and low expression of CD34 (P < 0.05) and CD17 (P<0.05). Sequence analysis of these NPM1 mutant cases revealed 5 known mutations (type A, B, D, N(M), and P(M)) and 1 novel variant (named as type S). CONCLUSIONS: NPM1 exon 12 mutations occur with a considerable percentage in AML patients with normal karyotype, M1/M5 subtype and older age, and are associated with higher peripheral white cell count and lower expression of CD34 and CD117.

[The molecular characteristics of T-cell immune reconstitution in leukemia patients after allogeneic hematopoietic stem cell transplantation].

OBJECTIVE: To study the molecular characteristics of CDR3 repertoires of T cell receptor beta chain variable region (TCRBV) of T lymphocytic clones in leukemia recipients after allogeneic hematopoietic stem cell transplantation ( allo-HSCT). METHODS: RT-PCR was used to amplify 24 subfamily genes of TCRBV from peripheral blood (PB) lymphocytes in twenty-four leukemia patients underwent three kinds of allo-HSCT and in five normal donors as control. The PCR products were further analyzed by genescan to evaluate the clonality of BV subfamily and characteristics of CDR3 and calculate usage rate of BV subfamily. The monoclonal bands which associated with GVHD and CMV infection were obtained by denaturation polyacrylamide gel electrophoresis and sequenced. Comparison of the sequences of TCRBV CDR3 with other CDR3 sequences which associated with GVHD or CMV infection was reported. RESULTS: 2 approximately 19 months after transplantation, there were 6 approximately 14 BV subfamilies expressed and the polyclonal expression reached 33% in nine patients underwent haploidentical bone marrow transplantation(HI-BMT). In five patients underwent matched unrelated peripheral blood stem cell transplantation ( MU-PBSCT), there were 10 approximately 15 BV subfamilies expressed of which 45% were poly-clones. In 10 patients underwent matched sibling bone marrow transplantation(MS-BMT), 10 approximately 16 BV subfamilies were expressed and more than 48% of them were poly-clones. Monoclones and oligo-clones existed in 24 BV subfamilies but no common one monoclone BV subfamilies was found. Immune reconstitution in patients underwent HI-BMT was later than that in other two groups. In 2 patients TCRBV was detected in 2m and 3m after allo-HSCT and found that there was a tendency of increasing usage of BV subfamilies and increasing expression of CDR3 polymorphism. Twenty three TCRBV CDR3 molecules associated with GVHD and CMV infection were compared each other by bioinformatics and found that different cases of the same BV subfamilies may share similarity in amino acid motif, while in different BV subfamilies none appeared to share the same amino acid motif. CONCLUSION: In 1.5 years after allo-HSCT, the usage of TCRBV subfamilies still restricted. Immune reconstitution in patients underwent HI-BMT was later than that in other two groups. TCRBV CDR3 molecules associated with GVHD and CMV infection showed that different cases of the same BV subfamilies may share similarity in amino acid motif, while in different BV subfamilies none of clones appeared to share the same amino acid motif.

[A clinical study of 31 patients with malignant hematopoietic disease treated with non-T cell-depleted HLA-haploidentical hematopoietic stem cell transplantation].

OBJECTIVE: To investigate the effects and prognosis of malignant hematological disease after HLA haploidentical hematopoietic stem cell transplantation (H-HSCT) without T-cell depletion. METHODS: The clinical data of 31 cases with malignant hemopoietic disease treated with H-HSCT from July 2002 to July 2006 were analyzed, including 11 cases of standard risk and 20 of high risk. RESULTS: 30 patients achieved engraftment of a median of 13 and 22 days for neutrophil and platelet, with an accumulative incidence of II - IV grade acute graft-versus-host disease (GVHD) 61.3%, and an accumulative incidence of chronic GVHD 41.9%. 13 patients survived with Karnofsky scale over 90.0% after a median follow-up of 24 months. 33 months of accumulative survival was 62.3% in the standard risk group and 35.0% in the high risk group. The CD(3)(+) T cells count of the graft and the disparity of HLA-A, B, DR loci were the major factors of impact on acute GVHD. CONCLUSION: HLA H-HSCT is an effective therapeutic method for malignant hematological disease, CD(3)(+) T cells count of the graft and the disparity of HLA-A, B, DR loci are the major factors of impact on acute GVHD.

Patterns of T-cell reconstitution by assessment of T-cell receptor excision circle and T-cell receptor clonal repertoire after allogeneic hematopoietic stem cell transplantation in leukemia patients--a study in Chinese patients.

OBJECTIVE: Successful allogeneic hematopoietic stem cell transplantation (HSCT) requires reconstitution normal T-cell immunity. Measurement of T-cell receptor excision circles (TRECs) and T-cell receptor beta (TCRBV) CDR3 repertoire is a means of quantifying recent thymic T-cell production and reflecting antigen-specific T-cell clones proliferation. METHODS: We used real-time quantitative PCR to detect TRECs from 43 Chinese patients who underwent three kind of allo-HSCT without T-cell depletion. RT-PCR was performed to amplify 24 subfamily genes of TCRBV in 24 patients of them. RESULTS: For haploidentical-D group, the TRECs numbers were lower up to 24 months. For matched-sibling donor (MSD) group, the recovery of TRECs was faster than those of other two groups. TRECs values in matched-unrelated donor (MUD) were in the middle. During 2-19 months after transplantation, there were 6-16 BV subfamilies expressed and 33-48% of them were polyclones. The usage rate of TCRBV and percentage of polyclones in haploidentical-D were less than those of other two groups. Twenty-three CDR3 molecules were obtained from nine patients who were potentially associated with GVHD or CMV infection. CONCLUSIONS: Analyzing the changes of TCRBV repertoire and measuring TRECs during immune reconstitution would be useful to determine the host's current immune status and ability of T-cell immune reconstitution and also to find antigen-specific T-cell clones in the three kinds of HSCT.

[Molecular characteristics of T-cell receptor of clonal expansion of T lymphocytes in leukemia patients after haploidentical bone marrow transplantation].

BACKGROUND & OBJECTIVE: Previous clinical and experimental results indicate that T-cell immune reconstitution is slow after hematopoietic stem cell transplantation. Immune reconstitution after haploidentical bone marrow transplantation (BMT) is closely related to clinical events. This study was to analyze the repertoire of T-cell receptor beta chain variable region (TCRBV) and the molecular characteristics of T-cell clones during immune reconstitution in leukemia patients after haploidentical BMT. METHODS: Reverse transcription-polymerase chain reaction (RT-PCR) was used to amplify 24 genes of TCRBV subfamily from peripheral blood lymphocytes of 9 leukemia patients after haploidentical BMT, and 5 healthy donors as control. The PCR products were analyzed by GeneScan to evaluate the clonality of BV subfamily, characteristics of complementarity determining region 3 (CDR3), and usage rate of BV subfamily. Graft-versus-host disease (GVHD)-related monoclonal bands were sequenced. RESULTS: During 10-19 months after haploidentical BMT, the usage of TCRBV subfamily was still restricted. Deletion of some BV subfamily members was detected, while others expanded in monoclonal or oligoclonal. For 4 patients with stable disease, the expression of 9-14 BV subfamily members was detected, and more than 50% of them were polyclones. For other 5 patients with GVHD or cytomegalovirus (CMV)-pp65 infection, the usage of TCRBV decreased obviously(P<0.05), the expression of CDR3 were monoclonal or oligoclonal, only 30% were polyclonal. No common monoclonal BV subfamily members were detected. After treatment, the usage of BV subfamily and CDR3 polymorphism were increased in 2 patients. By analyzing the sequences associated with GVHD, none of the clones appeared to share any similarity in amino acid motif. CONCLUSIONS: In 10-19 months after haploidentical BMT, the usage of TCRBV subfamily members is still restricted. In stable condition, there are 9-14 BV subfamily members expressed and dominated by polyclones. In active condition, the expression of BV subfamily members is decreased and dominated by monoclones or oligoclones. A group of CDR3 molecules related to GVHD show no common amino acid motif to be shared.

[Role of CD28/CTLA-4 co-stimulators in immune pathophysiology of aplastic anemia].

OBJECTIVE: To explore the possible role of CD28/CTLA-4 co-stimulators in immune pathophysiology of acquired aplastic anemia(AA). METHODS: By FACS, the percentages of CD28, CTLA-4 expressing CD3+ CD4+ T cells and the level of Th1, Th2 in bone marrow were detected in 23 AA patients at active phase, 10 at recovery phase and 15 normal controls. The relationship between the co-stimulators, Th1, Th2, and absolute neutrophil counts (ANC) was evaluated. RESULTS: (1) The percentage of CD28 and CTLA-4 expressing CD3+ CD4+ T cells in bone marrow, and CD28+/CTLA-4+ ratios were (31.40 +/- 10.83)%, (2.45 +/- 1.30)% , and 17.02 +/- 13.44 in normal controls respectively, (39.84 +/- 10.89)%, (1.43 +/- 0.67)%, and 43.04 +/- 37.61 in AA at active phase, respectively, (22 +/- 9.08)%, (3.46 +/- 2.26)%, and 10.49 +/- 7.8 in AA at recovery phase, respectively. The percentage of CD28 and CD28+/CTLA-4+ ratio were significantly higher, while CTLA-4 were lower in active phase AA patients than in normal controls (P < 0.05). These values in recovery phase AA were comparable to those in normal controls. (The Th1, Th2, and Th1/Th2 in bone marrow were (4.21 +/- 2.11)%, (1.99 +/- 1.27)%, and 2.46 +/- 1.28 in normal controls respectively, (11.13 +/- 4. 96)%, (2.46 +/- 1.65)%, and 5.20 +/- 1.98 in active phase AA and (5.39 +/- 4.2)9%, (2.53 +/- 2.41)%, and 2.87 +/- 1.43 in recovery phase AA, respectively. The percentage of Th1 and Th1/Th2 ratio were significantly higher in AA patients at active phase than in normal controls (P < 0.05). (3) The CD28+/CTLA-4+ ratio was positively related to the Th1+ /Th2+ ratio (P < 0.05). ANC was negatively related to CD3+ CD4+ CD28+ T cells (P < 0.01), and positively to CD3 + CD4 ' CTLA-4' T cells (P < 0.01) respectively. CONCLUSION: (1) The expression of CD28 was increased while CTLA-4 decreased on the membranes of CD3+ CD4+ T cells in bone marrow of AA patients. (2) The abnormal expression of CD28 costimulator promoted the shift of immune balance to Thl type. (3) The unbalance of CD28+ / CTLA-4+ is important for the immune pathophysiology of AA.

[Quantitative analysis of donor chimerism in adoptive immunotherapy following allogeneic hematopoietic stem cell transplantation].

OBJECTIVE: To investigate the value of sequential and quantitative analysis of donor chimerism (DC) to predict the outcome of allogeneic hematopoietic stem cell transplantation (allo-HSCT), to determine the optimal time point of adoptive immunotherapy and to estimate the efficacy of adoptive immunotherapy. METHODS: Quantitative analysis of DC was performed with multiplex PCR amplification of short tandem repeats markers (STR-PCR) and capillary electrophoresis with fluorescence detection in 84 patients who received allo-HSCT. Sequential chimerism both prior to and following adoptive immunotherapy were evaluated in 16 patients. RESULTS: Increase of mixed chimerism and decrease of DC < 90% were found in 22 of the 84 patients. Six of the 22 patients who did not receive donor lymphocyte infusion (DLI) all died of relapse. Adoptive immunotherapy was used to treat the remaining 16 patients. Before the time of relapse or graft rejection, STR-PCR indicated decrease of DC in 12 of the 16 patients, with levels ranging from 24.8% - 86.2%. A response to immunotherapy was achieved in 11 of the 16 patients (68.8%). In these patients, the value of DC increased with conversion to a predominant donor profile (> or =90%). 6 of the 11 patients converted to stable full donor chimerism (FDC) and 5 of the 11 patients to transformed stable mixed chimerism (MC) shortly after immunotherapy. All these 11 patients who responded to immunotherapy developed graft versus host disease (GVHD). While in the patient without response, the level of DC decreased persistently or declined after a transient increase. Three patients without response received second DLI but still failed to response. CONCLUSION: The results demonstrate that sequential and quantitative monitoring of DC can identify the patients who have high risk of relapse or graft failure and can be used to guide adoptive immunotherapy at early stage to improve the response of immunotherapy in those patients who undergo cytogenetic or molecular relapse. Furthermore the serial and quantitative detection of DC has been shown to be a valuable tool to evaluate early the efficacy of treatment. As well, it can present a rational basis for treatment intensification in patients who did not respond to first-line adoptive immunotherapy treatment.

[Mobilization of peripheral blood stem cells with mitoxantrone and high-dose cytarabine chemotherapy and rhG-CSF in patients with hematopoietic malignancies].

OBJECTIVE: To evaluate the efficacy of mitoxantrone combined high dose of cytarabine and recombinant human granulocyte colony-stimulating factor (MAG) regimen for mobilizing autologous peripheral blood stem cells (APBSC) in patients with hematopoietic malignancies. METHODS: From December 1995 to April 2003, 14 lymphoma and 29 acute leukemia patients were treated with high-dose cytarabine (2 g/m2 every 12 h, days 1 and 2) and mitoxantrone (10 mg/m2, days 2 and 3), followed by 300 microgram recombinant human granulocyte colony-stimulating factor per day (rhG-CSF 300 microg/d) i.e, the MAG regimen as mobilization regimen of peripheral blood stem cells. rhG-CSF was given subcutaneously when the white blood cell (WBC) count below 1.0 x 10(9)/L following the MA chemotherapy, APBSC were harvested when WBC count increased using Baxter CS3000plus or Cobe Spectra. RESULTS: Mobilization was successful in 13 of 14 lymphoma patients with MNC (3.91 +/- 2.70) x 10(8)/kg, CD34+ cells (17.79 +/- 12.90) x 10(6)/kg. Meanwhile, mobilization was successful in 24 of 29 acute leukemia patients with average of 2.13 times for apheresis. The median MNC and CD34+ cells yielded were 3.62 x 10(8)/kg and 7.37 x 10(6)/kg respectively, rhG-CSF was used for a median time of 7 days. Excepting for grade I-II gastrointestinal toxicity in 8 and infection in 14 cases, no major side effects were observed. There was no mobilization-related mortality. Minimal residual diseases became undetectable after mobilization in some patients. CONCLUSION: MAG is a safe and highly effective mobilization regimen in patients with lymphoma and acute leukemia.

[Application of sequential and quantitative analysis of donor chimerism in donor lymphocyte infusion].

In order to study the value of sequential and quantitative analysis of chimerism in determination of optional time of donor lymphocyte infusion (DLI) and prediction of efficacy of DLI, six patients with leukemias who relapsed or failed of engraftment were treated with DLI. Serial and quantitative analyses of donor chimerism (DC) both prior to and following DLI were performed by multiplex PCR amplification of STR markers (STR-PCR) and capillary electrophoresis with fluorescence detection. The results showed that at the time of relapse or graft rejection, STR-PCR indicated the decreasing donor chimerism in all six patients, at levels ranging from 27.3% to 85.7%. The declining value of DC (<90%) was detected in four patients at 26 days before relapse or graft rejection diagnosed clinically. Therefore the decrease of value of DC can be identified the high risk of relapse or graft failure and can be used to guide DLI implementation at early stage. In this study the clinical response were seen in two patients, the value of DC in these patients increased with convertion to a predominant donor profile (>90%) or converted to stable FDC shortly after DLI, while in the patients without clinical response, the level of DC decreased persistently or declined after transient increase. Three patients without response received second DLI. It is concluded that the monitoring of chimerism is proved to be a valuable to determine the optional time point of DLI and to early evaluate the efficacy of DLI. Furthermore, it can present a rational basis for treatment of intensification in the patients who did not respond to first-line DLI treatment.

[Application of sequential and quantitative monitoring of chimerism in allogeneic hematopoietic stem cell transplantation].

OBJECTIVE: To establish multiple short tandem repeat (STR) amplification by fluorescence labeling polymerase chain reaction (PCR) combined with capillary electrophoresis for quantitative determination of chimerism, and to evaluate the status of engraftment and predict the outcome of allogeneic hematopoietic stem cell transplantation (allo-HSCT). METHODS: Thirty-one patients received bone marrow transplantation (BMT) or nonmyeloablative allogeneic stem cell transplantation (NST) were evaluated. Peripheral blood and bone marrow were co-llected before and after transplantation in different period. Nine different STR markers were co-amplified in a single reaction by using a commercial AmpF/STR Profiler Plus PCR amplification kit. Separation of the PCR products and fluorescence detection were performed by ABI prism 310 Genetic Analyzer with capillary electrophoresis. The Genescan and Genotype software were used for size calling and quantification of peak areas. The formula to calculate donor chimerism values was based on the different allelic distribution type between donor and recipient. RESULTS: 48.4% of the patients received sex-matched transplantation and the quantification of donor chimerism could only be performed by STR-PCR method. Comparison of values obtained by FISH analysis with that by STR-PCR in patients transplanted from sex-mismatched donors showed an excellent correlation. The median number of informative alleles was 6.7 (range 2 - 10). The donor's alleles appeared in all the patients on day 7 post-transplant. The median values of donor chimerism in BMT group were inferior to that in NST group on day 7, day 14 and 1 month post-transplant. However the difference disappeared in the midterm or later period of transplant. On day 21, all of the 31 patients had stable engraftment and the percentage of donor chimerism was more than 92%. Median follow-up was 17 (3.5 - 29.0) months after transplantation. Twenty-six of 31 patients had durable engraftment and donor chimerism ratio was more than 90%. So for all of them survived leukemia-freely. Four of the 31 patients had unstable mixed chimerism and relapsed within 6 months post allo-HSCT. Another patient with unstable mixed chimerism appeared graft rejection. Decreasing values of donor chimerism were detected prior to the occurrence of graft rejection and disease relapse. The incidence of GVHD was much higher in the group of full donor chimerism. CONCLUSION: Sequential and quantitative monitoring of STR is a valuable tool for studying engraftment dynamics, graft rejection, and relapse and for predicting GVHD. Furthermore it can provide a basis for early intervention of clinical treatment.