Clinical significance of detection of T-cell subgroups in patients with aplastic anemia / 中国实验血液学杂志

The study was aimed to investigate the changes of T-cell subgroups in the peripheral blood (PB) of patients with aplastic anemia (AA) and the relationships between these changes and the pathogenesis of AA and the immunosuppressive therapeutic effects in AA, in order to provide a basis for selecting rational therapy of AA patients. T-cell subtype and the ratio of CD4+/CD8+ cell in the PB of 88 AA patients which had been diagnosed clearly and given conventional therapy or conventional therapy combined with immunotherapy were analyzed by tri-colour fluorescence-labeled monoclonal antibody and using multiparameter flow cytometry. The patients with AA were divided into normal type of ratio, inverted type of ratio, hypernormal type of ratio according to the ratio of CD4+/CD8+ cell in normal group, and then the relations of these subtype with patients' conditions and therapeutic effects were investigated. The results showed that the percentage of normal type of ratio in all patients was 39.8%, the percentage of inverted type of ratio in all patients was 44.3%, The percentage of hypernormal type of ratio in all patients was 15.9%. In the conventional therapy alone, there was no significant difference on therapeutic effects among these three immunological subtypes. In combined immunotherapy, total therapeutic efficacy of AA patients with inverted type of ratio and AA patients with immunologic abnormality (inverted type + hypernormal type) was 84.2% and 82.6% respectively, which were more than that in conventional therapy (45.5% and 42.8%) (p < 0.05). Total therapeutic efficacy in these patients was better than that in AA patients with normal type. It is concluded that significant abnormal ratios of CD4+/CD8+ exist in the majority of AA patients, abnormal ratios of CD4+/CD8+ both may be showed as increase or decrease, immunologic abnormality may play a role in pathogenesis of the patients with AA. The detection of PB T-cell subtype in patients with aplastic anemia contributes to evaluation of patients' condition and choice of rational treatment prescription, and enhancement of diagnostic level and therapeutic efficacy significantly, which is an important indicator for therapeutic strategy also.

Identification of a novel mutation of F (13) A gene in a pedigree with factor XIII deficiency / 中华血液学杂志

<p><b>OBJECTIVE</b>To explore F (13) A gene mutation in a pedigree with hereditary coagulation factor XIII (FXIII) deficiency.</p><p><b>METHODS</b>The FXIII deficiency was diagnosed by clot solubility test and other standard laboratory clotting tests. All exons, exon-intron boundary sequences of F(13) A gene were amplified by PCR and the products were sequenced directly. Any mutation identified by direct sequencing was confirmed by reverse sequencing. The mutation identified in the proband was screened in the family members.</p><p><b>RESULTS</b>The assays of PT, Qiulan, fibrinogen leveling, platelet counts, bleeding time were normal and the clot solubility test was positive in the proband. The homozygous deletion of 33 nucleotides (127067de133) in exon 10 of F(13) A gene which resulted in deletion of 11 amino acids in FXIIII A protein with 720aa residues was identified in the proband. Family studies showed that the mutation was inherited from the parents both of whom carried the heterozygous deletion mutation.</p><p><b>CONCLUSION</b>The homozygous 127067de133 mutation of F(13) A gene is responsible for the disorder of the pedigree.</p>

A novel mutation in antithrombin gene results in hereditary antithrombin deficiency / 中华血液学杂志

<p><b>OBJECTIVE</b>To investigate the antithrombin (AT) activity (AT: A) and AT antigen (AT: Ag) level in a Chinese family with type I antithrombin (AT) deficiency, and to explore the molecular mechanism of AT deficiency.</p><p><b>METHODS</b>Immuno-nephelometry and chromogenic assay were used to detect the plasma level of AT: A and AT: Ag, respectively. Genomic DNA was isolated from the peripheral blood, and all the seven exons and exon-intron boundaries of AT gene were amplified by PCR and direct sequencing.</p><p><b>RESULTS</b>The plasma levels of AT: A and AT: Ag of the proband were 45% and 97 mg/L, respectively, which led to a type I AT deficiency. A heterozygous T to A mutation was found at nucleotide 9833 in exon 5 resulting in a Tyr363Stop nonsense mutation. The sequencing results from the pedigree indicated that four other members also had this mutation.</p><p><b>CONCLUSION</b>This heterozygous nonsense mutation of T9833A in exon 5 resulting in venous thrombosis is a novel genetic defect of hereditary AT deficiency, which has not been described before.</p>

Severe hereditary coagulation factor V deficiency caused by two novel heterozygous mutations / 中华血液学杂志

<p><b>OBJECTIVE</b>To identify gene mutations of a pedigree with inherited factor V (FV) deficiency.</p><p><b>METHODS</b>The activated partial thromboplastin time (APTT), prothrombin time (PT), FV activity (FV:C) and FV antigen (FV:Ag) tests were performed for phenotypic diagnosis. The genomic DNA was extracted from the peripheral blood of the proband and all the 25 exons and their flanks of FV gene were amplified by polymerase chain reaction (PCR). The PCR products were screened by direct sequencing and the mutations were further confirmed by restriction enzyme digestion.</p><p><b>RESULTS</b>APTT, PT, TT, FV:C, FV:Ag of the proband were 249.2 s, 46.6 s, 17.9 s, 0.1% and 1.5%, respectively. FII, FVII, FVIII, FIX, FX activities, vWF and Fg were within normal ranges. Taking the GenBank Z99572 sequence as the reference, four mutations were identified in FV gene of the proband. They were a heterozygous two bases deletion in exon 13 (2238 approximately 2239delAG) introducing a frameshift and a premature stop at codon 689, and a heterozygous missense mutation in exon 23 (G6410T) resulting in the substitution of Gly for Val at codon 2079, respectively. The proband's father and mother were heterozygous for G6410T and for 2238 approximately 2239delAG, respectively.</p><p><b>CONCLUSION</b>The severe FV deficiency of the proband is caused by a frameshift mutation of 2238 approximately 2239delAG and a missense mutation of G6410T, which haven't been identified before.</p>

Fibrinogen beta chain gene mutation contributes to one congenital afibrinogenemia / 中华血液学杂志

<p><b>OBJECTIVE</b>To identify the fibrinogen (Fg) gene mutations in a Chinese pedigree of congenital afibrinogenemia.</p><p><b>METHODS</b>The plasma Fg activity and protein of the proband and his family members were detected. Genomic DNA was isolated from the peripheral blood mononuclear cells. All the exons and exon-intron boundaries of fibrinogen gene were amplified by PCR and sequenced thereafter.</p><p><b>RESULTS</b>Two mutations, 7972 del G in FGB and T2543A in FGG, were found in the proband.</p><p><b>CONCLUSIONS</b>FGG2543 is a polymorphism site, which lead to the polymorphism of gamma144 I/K. The G deletion at base 7972 of FGB contributes to the frameshift mutation after amino acid 419, resulting in the truncated beta chain without the terminal 27 amino acids. The latter may contributes to the pathogenetic mechanisms in Chinese congenital afibrinogenemia patients. The G deletion at base 7972 of FGB is identified for the first time.</p>