[Analysis on Polymorphism of Platelet Antigen Gene in Shandong Han Population].

OBJECTIVE: To study the Polymorphism of the human platelet antigen(HPA) gene 1-17 and human leukocyte antigen(HLA) gene-A and B locus in Shandong Han population. METHODS: A total of 962 samples from routine voluntary platelet donors were genotyped for HPA1-17 system and HLA-A site, B by PCR-SSP and PCR-SSOP respectively．Gene frequencies were calculated by counting. HPA1-17 and HLA genotype combinations were analyzed by Arelequin 3.5. RESULTS: The gene frequencies of HPA-la, -1b, HPA-2a, -2b, HPA-3a, -3b, HPA-4a, -4b, HPA-5a, -5b, HPA-6a, -6b, HPA-15a, -15b were 0.9918, 0.0082, 0.9419, 0.0592, 0.5841, 0.4174, 0.9969, 0.0031, 0.9892, 0.0108, 0.9835, 0.0175,0.5488 and 0.4512, respectively． The most common HPA genotype combination was HPA-(1, 2, 4, 5, 6, 7-14, 16, 17) aa-3ab-15ab (0.2048). Moreover, HLA-A*2(0.3094) and HLA-B*13(0.1513) showed the highest frequency in their respective locus. The most common HLA genotype combination was HLA-A*2-B*13(0.1397) . CONCLUSION: Distributions of HPA and HLA show high polymorphism in Shandong Han population. The ethnic and territorial difference of HPA distribution is also confirmed. It is imperative to establish local genetic database of volunteer platelet donors.

[Effects of Apheresis Platelets Treated with Vitamin B2 Photochemical Technology on the Release of White Blood Cells- and Platelet-Derived Cytokines during Storage].

OBJECTIVE: To investigate whether vitamin B2 photochemical pathogen reduction technology(PRT) treatment may lead to increase white cell- and platelet- derived cytokines release from platelets during storage. METHODS: Sixty milliliters of leukodepleted apheresis platelets were collected from 20 healthy donors, then were divided into 2 parts: one part (30 ml) remained untreated to serve as control, while the other part was treated with vitamin B2-UVB photo-chemical technology as experimental group. During 7 d of storage under standard blood bank conditions, platelet coun-ting (PC), platelet distribution width (PDW), mean platelet volume (MPV), white cell-derived cytokines (IL-1ß, IL-2, IL-6, IL-8, TNF-α and IFN-γ) and platelet-derived cytokines (CCL3, CCL5, TGF-ß-1 and PF4), P-selectin and phosphatidyl serine (PS) were analyzed on day 1, 3, 5 and 7 of storage, respectively. RESULTS: No signi-ficant differences were observed on PC, PDW and MPV between the experimental and control groups, respectively. The higher levels of platelet-derived cytokines were detected and reached a plateau after 5-7 days of storage, and the cyto-kines showed significant increase in experimental group compared with the control group. PS expression increased signi-ficantly in experimental group as compared with control group on day 3, 5 and 7 of storage, respectively. The accumula-tion of P-selectin was significant higher in experimental group than that in control group on day 5 and 7 of storage (P<0.05). The white cell-derived cytokines were not elevated by PRT treatment during 7 days of storage. CONCLUSION: The PRT-treated platelets are the main source of released cytokines during storage of PRT treatment. The levels of platelet-derived cytokines reach a plateau after 5-7 days of storage, most likely due to accelerated platelet activation and apoptosis.

[Identification of a novel HLA allele, HLA-DRB1*03:80, by sequencing-based typing].

This study was aimed to identify a novel HLA-DRB1 allele from a Chinese potential hemopoietic stem cell donor of Northeast China. A rare HLA-DRB1 allele was initially detected by Luminex PCR-SSO typing, then the sample was sequenced by sequence-based typing (SBT) and the alignments of sample's alleles was identified by single allele-specific sequencing strategy. The results revealed the existence of a new allele which differs from the closest matching allele DRB1*03:06 by a single nucleotide substitution at position 239, where C→G in exon 2, resulting in an amino acid exchange from Thr to Arg at codon 51. It is concluded that a novel allele has been confirmed and its name DRB1*03:80 is officially assigned by the WHO Nomenclature Committee in February 2012.

[Effects of N-Arachidonoylethanolamine on the quality of platelets stored in M-sol platelet preservative solution in vitro].

This study was purposed to investigate the effects of N-Arachidonoylethanolamine (ANA) on the quality of platelets (Plt) stored in Plt M-sol preservative solution at 22 ± 2°C. Samples taken from collecting apheresis Plt by the Amicus instrument and splited into two equal parts were stored in Plt M-sol preservative solution on a shaker at 22 ± 2°C. Different working concentrations of ANA (from 0.1 to 50 µmol/L) were then added into one part of stored Plt as the experimental group, the other without ANA was used as the control group. The viability of Plts stored at 22 ± 2°C for 7 days was evaluated by MTT colorimetric assay. The most effective concentration of ANA was selected and added to the subsequent experimental group. Plt count (BPC), mean Plt volume (MPV), Plt distribution width (PDW), phosphatidyl serine (PS) and soluble P-selectin were detected on the 1(st), 5(th), 7(th), 9(th) and 11(th) day of storage. The results showed that the most effective working concentration of ANA was 0.5 µmol/L, which showed significant increasing Plt viability (91.23 ± 5.44%) compared to the control group (62.54 ± 4.79%). Thus, ANA concentration at 0.5 µmol/L was choose to perform subsequent experiments. During 11 days of storage, the BPC, MPV and PDW were not changed significantly between the experimental group and control group, although there was decreasing trend in the BPC and increasing trends in MPV and PDW in the two groups. The rate of Plt PS positive was enhanced during the storage period: the rate of PS positive in experimental group increased from 7.69 ± 1.82% to 10.74 ± 1.78% while it in control group increased from 11.21 ± 2.03% to 15.37 ± 1.95%, with significant differences between the two groups (P < 0.05) on the 9(th) and 11(th) day of storage, respectively. Soluble P-selectin contents in experimental group on the 9(th) and 11(th) day of storage were 30.19 ± 2.03 ng/ml and 34.52 ± 2.64 ng/mL, respectively, while those in control group were 39.18 ± 2.66 ng/ml and 43.23 ± 2.58 ng/ml, respectively, with significant differences between the two groups (P < 0.05). It is concluded that the extended storage of Plt in M-sol treated with low concentration ANA can potentially alleviate Plt storage lesions.

[Identification of a novel HLA-A allele A*11:01:37 by sequence-based typing].

OBJECTIVE: To identify a novel HLA-A allele in a Chinese Han individual. METHODS: One mismatch was observed in HLA-A locus in HLA typing for CMDP donors using bi-allelic SBT kit. A confirmatory test for novel HLA allele was performed with mono-allelic SBT kit. RESULTS: The DNA sequence was confirmed to be a novel HLA-A allele. There was 1 nucleotide differed from the closest matching HLA-A*11:01:01 at position 393(G→A), which resulting a change from GGG to GGA at codon 107, led to a silent mutation, conserving the amino acid Gly. CONCLUSION: A novel HLA-A allele was confirmed and officially named HLA-A*11:01:37 (Genbank accession number, JN209962) by the WHO Nomenclature Committee for Factors of the HLA System in January 2012.

Transcriptional regulation of the one-carbon metabolism regulon in Saccharomyces cerevisiae by Bas1p.

The mechanisms mediating responses to glycine withdrawal in budding yeast were studied using a genome-wide profiling approach. A striking pattern of repressed expression of genes with an enrichment for those involved in one-carbon metabolism and AMP biosynthesis was revealed. Sequence analysis of the promoters for the most severely repressed genes identified a conserved sequence, TGACTC, a known binding site for the transcription factors Gcn4p and Bas1p. Loss of BAS1 abolished or significantly reduced the repression of these genes in response to glycine removal but this phenotype was much less apparent in the absence of BAS2 or GCN4. Addition of a Bas1p-LexA fusion protein to a strain with a LexAop-LacZ fusion showed a strong glycine effect both in a BAS2 and a bas2 background. A Bas1p-VP16 fusion protein activated expression in a bas1bas2 strain but no glycine effect was observed while a Bas1p-Bas2p fusion protein activated expression to a lesser extent with a slight stimulation by glycine. These results suggest that glycine affects Bas1p activation of transcription rather than DNA binding and that Bas2p is not required for this affect. Glycine withdrawal repressed many of the same genes as addition of adenine, a process known to be dependent on Bas1p. However, the glycine response is independent of adenine repression, because glycine regulation occurs normally in ade strains. We did not see any difference in the degree of stimulation by glycine in the presence or absence of adenine even in Ade+ strains. Glycine regulation was also found to be dependent on an intact SHM2 gene, which encodes cytoplasmic serine hydroxymethyltransferase. A reporter plasmid containing a DNA sequence from the GCV2 promoter which confers glycine regulation on heterologous genes was introduced into the yeast deletion set to screen for genes required for glycine regulation. A number of genes, including BAS1 were required for activation by glycine but only the SHM2 gene was required for repression in the absence of glycine. We also showed that regulation of the SHM2 promoter by glycine requires Bas1p but not Bas2p or Gcn4p using a beta-galactosidase reporter. The response of the promoter to glycine required an intact SHM2 gene but was restored in a shm2 strain by addition of formate to the medium.