Objective To establish the Flow-FISH method for simultaneous detection of telornere length and cell differentiation antigen. Methods HL60, Raji, Molt4 cells were cultivated. Each step and the conditions of the Flow-FISH procedure were optimized, standardized and validated, then 14 acute leukemia patients were observed for the changes of telomere length combined with differentiation antigen after complete remission by the method. Results Cells were stained with Alexa Fluor(R) 647-labeled antibody. Anti-gen-anfibedy complexes were covalenfly cross-linked onto the cell membrane before telomere staining. Cells were hybridized with telomere-specific fluorescein isothiocyanate (FITC)-conjugated peptide nucleic acid (PNA) probes followed by being counterstained with propidium iodide(PI). Multicolor Flow-FISH was performed to analyze telomere length and differentiation antigen simultaneously. The patients showed longer telomere and lower antigen expression after complete remission. Conclusion The Flow-FISH method for simultaneous detection of telomere length and differentiation antigen was successfully established which might prove to be a promising means for leukemia research especially in those without special molecular markers.

Objective To discover the mutations of rare thalassemia genes by sequencing of α and β-globin genes,to understand the frequency of rare mutations and to enrich thalassemia gene mutation spectrum in Chinese population.Methods For the cases of phenotype and genotype inconsistent,the 1st generation of sequencing was performed for α or β-globin gene coding region sequence analysis.Results A total of 102 patients with rare thalassemia gene mutations were found by sequencing,including 79 cases of β-thalassemia with 35 kinds of mutant types,and 23 cases of α-thalassemia with 11 kinds of mutant types.Conclusion The thalassemia gene sequencing could reveal rare mutations in genes,identify the genotype of patients,provide important support for prenatal diagnosis of rare thalassemia families,and reduce the missing rate and birth rate of children with thalassemia.

Objective To summarize the geographical distribution,phenotype and genotype data of 206 thalassemia families underwent prenatal diagnosis to provide information for clinical genetic counseling and avoid the birth of severe thalassemia children.MethodsTotally,206 thalassemia families were collected from Southern Medical University Nanfang Hospital from January 2008 to December 2009.Genomic DNA was extracted from peripheral blood,villus,amniotic fluid or cord blood from the couples or the fetuses.Gap-polymerase chain reaction (gap-PCR) and reverse dot blot (RDB) technology were used to detect the common α and β-thalassemia mutations.DNA sequencing was used to detect the rare mutations.Follow-up visit were done half a year after the fetuses were born. Results The 206 thalassemia families came from 12 provinces and areas across China,including Heilongjiang province.Mutations detected in α-thalassemia families included --SEA/,-α3.7/,-α4.2/,αCS α/ and αQS α/,which were all included in the testing kit. While there were 4 kinds of β-thalassemia mutations,Gγ+ (A γδβ)0,-28(A→C),CD54-58(-TATGGGCAACCCT) and CD37(G→A),could not be identified with routine testing kit. The 57 α-thalassemia families consisted of 11(19.3％) severe thalassemia,induding 8 Bart's hydrops syndrome and 3 Hb H disease,26(45.6％) heterozygote and 20(35.1％) normal infants,and the 149 β-thalassemia majors families consisted of 28 (18.8％) severe thalassemia,82(55.0％) heterozygote and 39 (26.2％) normal infants.Among the β-thalassemia heterozygotes,there was one 13-trisomy.Follow-up visit found that babies with Bart ' s hydrops syndrome (n =8),Hb H disease (n =3),β-thalassemia majors (n =28) and β thalassemia heterozygote combined with 13-trisomy(n=1) were aborted.Conclusions Thalassemia was found in some north area other than south of China,which should be paid more attention by clinicians.Gap-PCR and PCR-RDB technology are effective measures for thalassemia prenatal diagnosis in identifying major thalassemia fetuses before their birth,thus reduce the birth rate of thalassemia baby.But missed diagnosis might exist during the screening,so it is necessary to perform DNA sequencing on those patients with positive symptoms and negative common genetic diagnostic results.At the same time,prenatal diagnosis of chromosomal disorders should not be neglected for high-risk families.

ObjectivesTo explore the roles of mean corpuscular volume(MCV),mean corpuscular hemoglobin(MCH) and hemoglobin A2 (HbA2) in the laboratory screening of thalassemia,and to find optimal screening modality for different conditions.Methods From September 2008 to May 2011,1384 subjects underwent thalassemia screening at Department of Obstertrics andGynecology of Nanfang Hospital.Of them,1036 cases were diagnosed with thalassemia (408 α-thalassemia,608 β-thalassemia,and 20 αβ compound thalassemia,thalassemia group) and 348 without thalassemia,non-thalassemia group.All subjects were screened respectively for MCV,MCH and HbA2.Analyses were performed in all subjects to assess the sensitivity,specificity,positive predictive value,negative predictive value and diagnostic accuracy respectively associated with MCV,MCH and HbA2 alone,combination of MCV and MCH,and combination of MCV,MCH and HbA2.Results( 1 ) In the thalassemia group,the sensitivity of MCV alone was 92.9％ (379/408) for α thalassemia,99.3％ (604/608) for β thalassemia and 100.0％(20/20) for αβ compound thalassemia.In the non-thalassemia group,the specificity of MCV alone was 75.0％ (261/348).(2) In the thalassemia group,the sensitivity of MCH alone was 92.9％ (379/408) in α thalassemia,99.0％ (602/608) in β thalassemia and 100.0％ (20/20) in αβ compound thalassemia.In the non-thalassemia group,the specificity of MCH alone was 72.7 ％ (253/348).(3) The sensitivity of Hb A2 alone was 67.4％ (275/408) for α thalassemia,97.5％ (593/608) for 3 thalassemia,and 100％ (20/20) for α3 compound thalassemia while it's specificity was 72.4％ (252/348) in the non-thalassemia group.(4)With positive indexes of MCV,MCH and MCV + MCH,when HbA2 ＞ 3.5％ it had a high value in [β-thalassemia screening,but when HbA2 ＜ 2.5％ it had little value in α-thalassemia screening.(5) As a single marker,MCV and MCH had better sensitivity,specificity,positive predictive value,negative predictive value and diagnosis accuracy than HbA2.MCV + MCH was the best for overall screening,but for [β thalassemia screening,MCV + MCH + HbA2 was the best.ConclusionsMCV and MCH are suitable for epidemic screening in a large population,physical examination and premarital check-up.Hb electrophoresis andthalassemiagenediagnosisarerecommendedforsubjectswithpositiveMCVandMCH indexes.Diagnoses of α and β-thalassemia gene are recommended for pregnant women with positive MCV and MCH indexes.

BACKGROUND: Recombinant adeno-associated virus 2(rAAV-2) has attracted considerable attention due to its nonpathogenic nature in contrast to other viral vectors such as adenoviral and retroviral vectors in gene therapy attempts.OBJECTIVE: To explore rAAV-2 transduction to bone marrow mesenchymalstem cell(BMSC) in vitro and evaluate the possibility of using rAAV-2 as a vector for gene therapy of acute myelogenous leukemia(AML).DESIGN: An open experiment with cells as the observational subjects.SETTING: Department of Hematology, Nanfang Hospital, Southern Medical University.MATERIALS: The experiment was conducted in the Department of Hematology, Nanfang Hospital, Southern Medical University from February to July 2004. We used passages 3 to 5 BMSCs derived from six de novo AML patients and four healthy volunteers in this study.METHODS: BMSC was isolated from 6 to 10 mL of bone marrow aspirates obtained from the iliac crests of the patients who had been diagnosed as having de novo AML and from those of healthy volunteers. The acquired BMSC was infected by rAAV-2 which contained enhanced green fluorescent protein (rAAV-2-eGFP) at different multiplicity of infection(MOI) (MOI = 1 × 102,1 × 103, 1 × 104, 1 × 105, 1 × 106, 1 × 107) . Then we observed through phase contrast fluorescent microscope and flow cytometer to evaluate green fluorescent protein(GFP) expression 10 to 14 days after transduction. GFP expression was observed as the rAAV-2-eGFP transduced BMSC cultured in vitro. We also observed the in vitro gene expression profile of GFP in rAAV-2-eGFP transduced BMSC which was selected by neomycin ( G418). First, we confirmed GFP expression in BMSC through phase contrast fluorescent microscope, then on flow cytometer to detect the percentage of GFP expression.MAIN OUTCOME MEASURES: The efficiency of rAAV-2-eGFP transduction to BMSC. GFP expression was observed through phase contrast fluorescent microscope and flow cytometer at different time points after transduction.rAAV-2-eGFP to BMSC derived from normal volunteers and AML patients had no significant differences. GFP began to express 10 to 14 days after transduction, and the transduction efficiency ranged from 0. 3% to 1.4%. By changing infection condition, we could not make a higher transduction efficiency( P ＞ 0.05) . One round infection of BMSC by rAAV-2-eGFP at a MOI of 1 × 105 was ( 1. 030 ± 0. 034) %, 3 rounds of infection of BMSC by rAAV-2-eGFP at a MOI of 1 × 105 was (1. 140 ±0. 036)%, and coinfected by LipofectAMINE was (1. 380 ± 0. 054)%. However, 293 cell line which was the package cell of rAAV-2 could be efficiently transduced by AML patients transduced by rAAV-2-eGFP at MOI = 1 × 105: The percentage of GFP expression cell gradually decreased from 1.14% at day 12 after transduction to 0. 6% as cell passaged from 2 to 3, and maintained at a level of 0. 5% to 0. 6% later on till 61 days after transduction. After selected by neomycin(G418) 1 month later, rAAV-2-eGFP transduced BMSCs could maintain a long-term GFP expression at a level of 6.0% in vitro without significant decay within 100 days of observation period after transduction.CONCLUSION: The advantages of rAAV-2 mediated gene transduction lie in safety, no immune response to the host, and long-term expression maintained by the target gene. rAAV-2 and BMSC can be used for in vitro gene therapy, and as a systemic gene delivery system, it might be an alternative for systemic gene therapy in the future.

Objective:To investigate the clinical efficacy of fluorescence in situ hybridization(FISH)in prenatal diagnosis of chromosomal aneuploidy.Methods:FISH and karyotyping analysis were done in 120 samples of amniotic fluid from pregnant women.Results:FISH analysis results were consistent with those of karyotyping,the dectecting rate can reach 100%for chromosomal aneuploidies.There was no significant difference in the preference for FISH or karyotying for prenatal diagnosis when facing high matemal age,multi-indications and other factors(P>0.05).FISH was better when biochemical datafor down's syndrome were positive (P=0.029),however karyotyping was better when there was abnormal fetal ultrasound scan(P=0.000).Conclusions:FISH can detect the chromosomal aneuploidy quickly and accurately,especially when biochemical data for down's syndrome were positive.FISH could be the first choice for prenatal diagnosis in the third trimester of high-risk pregnancy.

OBJECTIVETo study the expression of bcr/abl hybridized gene in chronic myeloid leukemia (CML), acute lymphatic leukemia (ALL) and polycythemia vera (PV), and its clinical significance.

METHODSThe bcr/abl hybridized gene of interphase metaphase cells of bone marrow in 67 such patients were investigated with a probe of dual color-dual fusion translocation fluorescence in situ hybridization (D-FISH).

RESULTSIn 38 CML patients, 34 (89.5%) were positive, with one having a typical t (9; 22) at first, which changed into negative after having been treated with interferon for 38 months. In another patient, 60 days after post-allogeneic peripheral blood stem cell transplantation (PBSCT), the cytomorphology and cytogenetics were in completely remission. But 3% cells were bcr/abl positive as detected by D-FISH. Six (25%) of 24 ALL patients were positive for Bcr/abl fusion gene, which was negative in 2 PV patients. Three patients suspected of having CML were also negative and one of these three was finally diagnosed as suffering from primary thrombocythemia and one, acute myeloid leukemia (M(2a)) as detected by ETO/AML(1) gene, though the other one was still not confirmed. Two (67%) of the 3 bcr/abl negative CML patients and 5 (87%) of the 6 bcr/abl positive ALL patients had refractory leukemia.

CONCLUSIONbcr/abl hybridized gene is accurately detected by a probe of dual color-dual fusion translocation fluorescence in situ hybridization, which can serve as an effective index for clinical diagnosis, estimation of prognosis and monitor of minimal residual disease in some hematopathies.

Adolescent ; Adult ; Aged ; Child ; Child, Preschool ; Female ; Fusion Proteins, bcr-abl ; genetics ; Humans ; In Situ Hybridization, Fluorescence ; methods ; K562 Cells ; Leukemia, Myelogenous, Chronic, BCR-ABL Positive ; drug therapy ; genetics ; physiopathology ; Male ; Middle Aged ; Polycythemia Vera ; genetics ; physiopathology ; Precursor Cell Lymphoblastic Leukemia-Lymphoma ; genetics ; physiopathology

OBJECTIVETo optimize pre-coated multiple-probe fluorescence in situ hybridization (FISH) to improve its efficiency in cytogenetic diagnosis of acute leukemia.

METHODSThe original multiple-probe FISH techniques were optimized by adjusting the cell density and adding a process of protease digestion. Cytogenetic anomalies were detected in 141 patients with acute lymphocytic leukemia (ALL) or acute myeloid leukemia/ myelodysplastic syndromes (AML/MDS) using the modified technique, and 35 of the patients were also examined using the original technique. The successful detection rate and positive site detection rate were compared between the modified and original techniques.

RESULTSModification of the pre-coated multiple-probe FISH technique resulted in an significant increase of the successful detection rate (from 85.3% to 100%) and the positive site detection rate (from 5.1% to 8.6%) in ALL patients; in AML/MDS patients, the successful detection rate was significantly improved from 67.4% to 99.8% and the positive site detection rate from 3.5% to 6.0% (P<0.01).

CONCLUSIONThe modified pre-coated multiple-probe FISH technique can significantly increase the diagnostic efficiency of cytogenetic abnormalities in leukemic patients.

Chromosome Aberrations ; Humans ; In Situ Hybridization, Fluorescence ; methods ; Karyotyping ; Leukemia, Myeloid, Acute ; diagnosis ; genetics ; Myelodysplastic Syndromes ; diagnosis ; genetics

OBJECTIVETo explore the association between chimerism, minimal residual disease (MRD) and relapse after sex-mismatched allogeneic hematopoietic stem cell transplantation (allo-HSCT) for leukemia.

METHODSFifty-seven patients with leukemia received allogeneic hematopoietic stem cell grafts from HLA-matched or partially matched, but sex-mismatched donors. Chimeric status and MRD were detected by dual-color interphase fluorescence in situ hybridization (I-FISH) using X/Y sex chromosome centromere DNA probe and bcr/abl dual fusion DNA probe, respectively, at different time points after transplantation. SPSS software was used to analyse the correlation between chimeric status, MRD and relapse.

RESULTSIn comparison with karyotype analysis, I-FISH was of higher sensitivity in detecting sex chromosome and bcr/abl fusion gene. Chimeric status was negatively correlated with MRD (r=-0.9690, P<0.01). In the early times of transplantation (within 3 months), mixed chimerism had higher relapse rate than did complete chimerism. Chimeric status and MRD were correlated with leukemic relapse (r=-8240, P<0.01; r=-0.9040, P<0.01). The decrease in chimeric status occurred before leukemic relapse in hematology.

CONCLUSIONI-FISH is a more specific and sensitive test for monitoring MRD after transplantation. The clinical value of sex chromosome is identical to that of the special tumor gene for monitoring MRD after transplantation. Chimeric status is negatively correlated with MRD. Chimeric status and MRD are associated with leukemic relapse. The decrease in chimeric status is considered a mark of leukemic relapse after transplantation.

Adolescent ; Adult ; Child ; Chromosomes, Human, X ; genetics ; Chromosomes, Human, Y ; genetics ; DNA Probes ; genetics ; Female ; Fusion Proteins, bcr-abl ; genetics ; Hematopoietic Stem Cell Transplantation ; methods ; Humans ; In Situ Hybridization, Fluorescence ; methods ; Leukemia ; genetics ; surgery ; Male ; Middle Aged ; Transplantation Chimera ; genetics ; Transplantation, Homologous ; Young Adult

OBJECTIVETo detect copy number changes of α-globin gene, and analyze molecular mechanism of the impacts of fetal hemoglobin (HbF) levels for α-globin gene copy numbers loss or increase.

METHODSA total of 15 cases with combined increased levels of fetal hemoglobin with β-thalassemia were collected. Firstly, three common α-thalassemia deletions were validated by Gap-PCR. Secondly, the largest deletions of the β-globin gene cluster were detected by multiplex ligation-dependent probe amplification (MLPA).

RESULTSAmong the 15 cases, there was 1 case with duplication of the α-globin gene cluster, 3 cases of SEA heterozygote deletion of the α-globin gene, 1 cases of α 3.7 deletion heterozygote of the α-globin gene, 1 case of alpha 4.2 deletion homozygote of the α-globin gene, 1 case of deletion homozygote in the like α-globin gene. A compound heterozygous for SEA and α 3.7 of the α-globin gene was also detected. However, 7 cases showed no copy numbers loss and increase of the the α-globin gene cluster.

CONCLUSIONAdditional α-globin gene can produce excessive α-chain, which can aggravate imbalance for α and β-chain, and cause clinical symptoms in patients with β-thalassemia. Yet, copy number loss or mutation in α-globin gene will cause a milder clinical phenotype.

Adult ; Asian Continental Ancestry Group ; genetics ; China ; DNA Copy Number Variations ; Female ; Fetal Hemoglobin ; metabolism ; Humans ; Infant ; Male ; Mutation ; Pedigree ; alpha-Globins ; genetics ; beta-Thalassemia ; genetics ; metabolism