Objective To study the gene expression profiles of megakaryocytes(MKs) from human cord blood CD34+ cells in vitro expanded and to understand megakaryopoiesis at the molecular level. Methods CD34+ cells were isolated using density gradient centrifugation and magnetic activated cell sorting. The cells were cultured and stimulated with recombinant human TPO ( 100 ng/ml). After 12 days, the MKs fraction was separated using an anti-CD41 monoclonal antibody by immunomagnetic sorting. The gene expression profiles of MKs, non-MKs as well as meg-01 cells were studied by gene chip assay. THBSI, HOX A9,β-actin, lL-8,Annexin A6, FGF-8 were selected to validate the gene chip results by RT-PCR. Results A total of 116 genes between MKs and non-MKs cells were significantly different, 52 genes were up-regulated and 64 genes were down-regulated. In addition, 158 genes between MKs and meg-01 cells were significantly different, 71 genes were up-regulated and 87 genes were down-regulated. THBSI showed higher expression in MKs than in non-MKs. HOXA9 showed lower expression in MKs than in non-MKs. The expression of β-actin did not show any significant difference in MKs and non-MKs. IL-8 showed higher expression in MKs than in meg-01 cells, while ANXA6 showed lower expression in MKs than in meg-01 cells. The expression of FGF-8 did not show any significant difference between MKs and meg-01 cells. Conclusions MKs, non-MKs and meg-01 cells show different gene expression profiles. The regulatory genes include stress response genes,immune related genes, DNA synthesis and repair genes, metabolism genes, pro-onco genes and tumor suppressor genes.

Objective To detect fetal RhCcEe genotype from fetal DNA in maternal plasma for noninvasive prenatal diagnosis.Methods DNA from maternal plasma sample was extracted by use of QIAamp DNA Kit. The existence of fetal DNA was confirmed by amplified fetal SRY gene. The fetal RhCcEe gene was amplified by polymerase chain reaction (PCR) from 30 pregnant maternal plasma. The results of fetal RhCcEe genotype were evaluated retrospectively by the serologic analysis of infant and pregnant woman RhCcEe phenotype.Results Among the 30 samples, 13 were the same phenotypes between mother and infant, 17 were different. When mother phenotypes were RhCC, cc, EE and ee homozygous, the deleted allele gene can be successfully amplified from mother plasma.Conclusion Noninvasive fetal RhCcEe genotyping is reliable. When the mother was homogyzous, genotyping the fetal CcEe alleles was very significant and useful for HDN (hemolysis disease of newborn) diagnosis and therapy.

0.05),but the numbers of CD41+ cells and platelets were increased significantly(P

OBJECTIVETo study the serological characteristics and molecular mechanism for a rare Pk phenotype of the P1Pk blood group system.

METHODSThe blood group of the proband was identified by serological techniques. The coding region and flanking intronic sequences of the β-1,3-N-acetylgalactosyltransferase gene (B3GALANT1) associated with the Pk phenotype were analyzed using polymerase chain reaction sequence-based typing.

RESULTSThe proband was identified as having a rare Pk phenotype including anti-P in her serum. The blood group of her daughter and husband showed a P2 phenotype. The nucleotide sequences of the B3GALANT1 gene of her husband and two randomly-chosen individuals were the same as the reference sequence (GenBank AB050855). Nucleotide position 433 C>T homozygous mutation in the B3GALANT1 was found in the proband, which has resulted in a stop codon at amino acid position 145, which may produce a premature protein capable of decreasing or inhibiting the activity of the β -1,3-N-acetylgalactosyltransferase. The nucleotide position 433 C/T heterozygous in the B3GALANT1 was found in her daughter.

CONCLUSIONThe Pk phenotype resulted from 433 C>T mutation in the B3GALANT1 gene has been identified.

ABO Blood-Group System ; genetics ; Adult ; Base Sequence ; Blood Grouping and Crossmatching ; Female ; Genotype ; Humans ; Male ; Molecular Sequence Data ; N-Acetylgalactosaminyltransferases ; genetics ; Pedigree ; Phenotype ; Point Mutation

OBJECTIVETo explore the molecular basis for an individual with rare p phenotype in the P1Pk blood group system.

METHODSErythrocyte blood group antigens and antibodies in serum were identified in the proband and five family members with a serological method. Coding regions and flanking untranslated regions of the α1,4-galactosyltransferase gene (A4GALT) encoding P1Pk antigens were amplified with polymerase chain reaction and directly sequenced. The haplotypes of A4GALT in the parents of the proband were also analyzed by cloning sequencing.

RESULTSThe proband was found with a rare p phenotype with anti-Tja antibody in his serum by serological method. The other family members all had a common P2 phenotype. The results of DNA sequencing showed that a cytosine was inserted at nucleotide position 1026 to 1029 (1026_1029insC) of both alleles of the A4GALT gene in the proband. The mutation has caused a reading frame shift and formed a mutant protein by extending 92 amino acid residues. The other family members were either heterozygous for the insertion or of the wild type at above position.

CONCLUSIONThe 1026_1029insC mutation of the A4GALT gene is probably responsible for the p phenotype identified for the first time in Chinese population. The individual with the p phenotype possesses anti-Tja antibody.

ABO Blood-Group System ; genetics ; Adult ; Alleles ; Asian Continental Ancestry Group ; genetics ; Base Sequence ; Female ; Frameshift Mutation ; Galactosyltransferases ; genetics ; Humans ; Male ; Molecular Sequence Data ; Mutagenesis, Insertional ; Pedigree ; Phenotype ; Young Adult

OBJECTIVETo delineate serological features and genetic basis for a rare p phenotype of P1Pk blood group system found in a Chinese individual.

METHODSSerological assaying was carried out for a proband with unexpected antibody found in his serum using specific antibodies and panel cells. Coding regions and flanking introns of α 1,4-galactosyltransferase gene (A4GALT) associated with the p phenotype were screened with polymerase chain reaction and DNA sequencing.

RESULTSA rare p phenotype of the P1Pk blood group system has been identified with red blood cells from the proband, whose serum contained anti-Tja antibody which can agglutinate and hemolyze with other common red blood cells. Other members of the proband's family were all normal with P1 or P2 phenotype. DNA sequencing has identified in the proband a homozygous 26 bp deletion at position 972 to 997 of the A4GALT gene. The deletion has caused a shift of the reading frame, resulting in a variant polypeptide chain with additional 83 amino acid residues compared with the wild-type protein. Other family members were either heterozygous for above deletion or non-deleted.

CONCLUSIONA 26 bp deletion at position 972 to 997 of the A4GALT gene has been identified in a Chinese individual with p phenotype.

ABO Blood-Group System ; genetics ; Alleles ; Base Sequence ; Galactosyltransferases ; genetics ; Genetic Association Studies ; Genotype ; Humans ; Male ; Molecular Sequence Data ; Pedigree ; Phenotype ; Sequence Deletion

OBJECTIVETo explore the function of a novel nonsense mutation c.1476G>A of ITGB3 gene using an in vitro expression system.

METHODSAn eukaryotic expression vector containing ITGB3 c.1476G>A cDNA was generated by site-directed mutagenesis and transformed into E.coli. Plasmid DNA was extracted and sequenced to confirm the target mutations. Wild-type and mutant recombination plasmids were transfected into Chinese hamster ovarian cancer (CHO) cells by nonliposome method, and the stable expression cells were harvested by G418 screening. The ITGB3 gene mRNA transcription and GPIIIa expression level in CHO cells were detected with real-time quantitative PCR, Western blotting and flow cytometry, respectively.

RESULTSThe eukaryotic expression vectors of wild ITGB3 cDNA and c.1476G>A mutant were successfully constructed. CHO cells with stable expression were obtained after transfection and screening. Compared with the wild-type transfected cells, the amount of CD61 antigen expression was 37% and mRNA transcription level was only 6% in the mutant-transfected cells. Full length GPIIIa protein was found only in the stably wild-type-transfected cells, but not in mutant-transfected cells by Western blotting analysis.

CONCLUSIONThe ITGB3 c.1476G>A mutation can decrease the transcription level and further affect GPIIIa synthesis and CD61 antigen expression.

Animals ; Base Sequence ; Blood Platelets ; cytology ; metabolism ; CHO Cells ; Cloning, Molecular ; Codon, Nonsense ; genetics ; Cricetinae ; Cricetulus ; Humans ; Integrin beta3 ; genetics ; metabolism ; Molecular Sequence Data ; Plasmids ; genetics ; metabolism ; Point Mutation

OBJECTIVETo analyze specific expression of blood group genes using nucleated erythroid cells cultured from un-mobilized peripheral stem cells in vitro.

METHODSHematopoietic stem cells(HSC) bearing the CD34 antigen were isolated from peripheral blood by centrifugation and magnetic beads sorting, followed by suspension culture in vitro. Cells were collected from medium on various stages and analyzed by immunofluorescence. The RNA transcription of RH and ABO blood group genes was analyzed using culture cells on day 12.

RESULTSA total of(3.19±0.13) ×10 (4) CD34+cells were isolated from about 50 mL peripheral blood with a recovery rate of 67.3%±2.7%. The cells amount in erythroid-lineage culture system on day 9 reached a plateau of a 237.1±15.5-fold amplification of the initial cell input. The stem cell-specific CD34 antigen was dropped off, while the erythroid-specific CD235a and CD240D antigens were increased in culture period. RHD/CE and ABO genes can be amplified using RNA extracted from culture cells on day 12, and genotypes of Rh and ABO systems by DNA sequencing were consistent with their serologic phenotypes.

CONCLUSIONA method was established to analyze the gene expression of erythroid blood group derived from un-mobilized peripheral stem cells cultured in vitro. It can be used to study the expression of various erythroid-specific genes.

Antigens, CD34 ; analysis ; genetics ; Base Sequence ; Blood Group Antigens ; analysis ; genetics ; Cells, Cultured ; Erythrocytes ; cytology ; Flow Cytometry ; Hematopoietic Stem Cells ; cytology ; Humans ; Molecular Sequence Data

OBJECTIVETo explore the molecular basis of an individual with Bel variant of the ABO blood group.

METHODSThe ABO antigen and serum antibody of the individual were detected by serological method. All coding regions and flanking introns of the ABO gene were amplified with PCR and sequenced bidirectionally. The haplotypes of the individual were analyzed by cloning and sequencing. A three dimensional model of the mutant protein was constructed and analyzed.

RESULTSThe individual has expressed a very weak B antigen on its red blood cells by absorption and elution testing, which was identified as a Bel variant phenotype. The heterozygous sites in exon 6 (261del/G) and exon 7 (297A/G, 484del/G, 526C/G, 657C/T, 703G/A, 796C/A, 803G/C, 930G/A) of the coding region of the ABO gene were identified by direct sequencing. Haplotype analysis showed that the individual has carried an O01 allele and a novel B allele. The sequence of the novel B allele was identical to B101 except for a del G at nucleotide position 484 (484delG), which was nominated as B120 by the Blood Group Antigen Gene Mutation Database (dbRBC NCBI). The 484delG mutation of the B allele has led to a reading frame shift and created a premature terminal codon for the glycosyltransferase (GT) enzyme. Prediction of the 3D structure suggested that the GT enzyme has become an incomplete protein only with its N-terminal region.

CONCLUSIONThe 484delG mutation of the glycosyltransferase B gene has probably abolished or reduced the enzymatic activity and resulted in the Bel variant phenotype.

ABO Blood-Group System ; genetics ; Alleles ; Base Sequence ; Exons ; Female ; Genotype ; Glycosyltransferases ; genetics ; Humans ; Molecular Sequence Data ; Mutation ; Sequence Deletion

OBJECTIVE: To analyze the molecular characteristics of a recombinant allele of the ABO blood group. METHODS: The ABO phenotype was determined with the tube method. The coding regions of the ABO and FUT1 genes were analyzed by PCR-sequence based typing. The ABO alleles of the proband were determined by allele-specific primer sequencing. The full sequences of the ABO gene of the proband and her mother were determined through next generation sequencing. RESULTS: The red blood cells of the proband did not agglutinate with anti-H, and the sequence of the FUT1 gene was homozygous for c.551_552delAG.The proband was thereby assigned as para-Bombay. Bi-directional sequencing also found that she was heterozygous for c.261G/del,467C>T,c.526C>G,c.657C>T,c.703G>A,c.796C>A,c.803G>C and c.930G>A of the coding regions of the ABO gene. Allele-specific primer sequencing also found her to carry a ABO*A1.02 allele and a recombinant allele from ABO*O.01.01 and ABO*B.01. The recombination site was located between nucleotide c.375-269 and c.526, and the allele was maternally derived. CONCLUSION An recombinant allele of the ABO gene has been identified, which has originated from recombination of ABO*O.01.01 with the ABO*B.01 allele.
ABO Blood-Group System/genetics* ; Alleles ; Blood Grouping and Crossmatching ; Female ; Fucosyltransferases/genetics* ; Genotype ; Humans ; Phenotype ; Recombination, Genetic