Analysis of the Physiological Activities and Functions in Vitro of Apheresis Platelets during Storage / 中国实验血液学杂志

<p><b>OBJECTIVE</b>To investigate the changes of physiological activities and functions in vitro of apheresis platelets during storage.</p><p><b>METHOD</b>17 units of apheresis platelets were randomly chosen and stored at 20 °C to 24 °C with agitation. Platelet counting (Plt), mean platelet volume (MPV), blood gases, pH value, glucose (Glu) concentration, lactate (LA) concentration, LDH concentration, thromboelastogram (TEG), hypotonic shock response (HSR), CD62p expression rate and anew expression rate were measured on days 0, 1, 3, 5 after platelet storage. Changes of physiological activities and functions in vitro were systematically evaluated by above-mentioned indexes.</p><p><b>RESULTS</b>During storage, Plt, MPV and HSR were not significantly changed; but pH value, blood gases, Glu, LA, LDH, HSR, expression rate of CD62p and anew expression rate were significant differenty. Among thromboelastogram indexes, R value increased obviously with prolongation of storage time; K value and αAngle were not significantly changed; MA was not significantly changed on day 1 and 3, but was slightly increase on day 5.</p><p><b>CONCLUSION</b>The physiological activities and functions in vitro of apheresis platelets are kept well during storage. For clinical transfusion of apheresis platelet during storage, clinical effect of transfusione is not influenced.</p>

Analysis of Patients' Irregular Antibody Screening and Identification Results before Blood Transfusion / 中国实验血液学杂志

<p><b>OBJECTIVE</b>To analyze the results of irregular antibody screening and identification among patients before blood transfusion, and to investigate the specific distribution of irregular antibodies and the distribution regularity in different diseases.</p><p><b>METHODS</b>Choosing the patients intended to be transfused in our hospital from January 1, 2009 to December 31, 2013 years, micro-column gel technique was used to screen the irregular antibodies of those receptors and to identify the antibody specificity of the positive specimens.</p><p><b>RESULTS</b>Among 44194 patients, 137 patients were with irregular antibody positive and their positive rate was 0.31%, among them 33 cases were male and accounted for 0.18% in the studied males; the 104 cases were females and accounted for 0.40% in all the studied females. The difference of sex distribution was statistically significant (X2=15.38, P<0.05). In the irregular antibody screening positive patients, patients with transfusion or pregnancy history were 129 cases, and the patients without transfusion or pregnancy history were 8 cases. In the irregular antibody screening positive patients, the main antibody of 54 cases belongs to Rh blood type system, accounting for 39.42%; The main antibody of 37 cases belongs to MNS blood type system, accounting for 27.01%; while the 30 cases belong to Lewis blood type system, accounting for 21.90%. According to the classification of diseases, the irregular antibody screening-positive patients with tumors were ranked in the highest rate at 5.96‰, the secondary hemorrhage of digestive tract and chronic renal failure were ranked at the rate of 3.28‰ and 3.19‰. The difference of positive rates between diseases was statistically significant (χ2=19.33, P<0.05).</p><p><b>CONCLUSION</b>Irregular antibody screening before blood transfusion is necessary, which can discover the irregular antibodies of clinical significance, especially for patients with tumors and the other patients with the history of frequent blood transfusions or multiple pregnancies. Antibody screening is a useful warning signal, as it ensures the safety of blood transfusions.</p>

Role of antioxidant in protecting the biological function of hematopoietic stem cells / 中国实验血液学杂志

In peripheral blood hematopoietic stem cell transplantation (PBHSCT) , the mobilization and circulating of bone marrow hematopoietic stem cells in blood with higher oxygen concentration all increase reactive oxygen species(ROS) production, which has negative effect on the biological function of BMHSC. In order to investigate the protective effect of antioxidant on hematopoietic stem cells (HSC), the ascorbic acid 2-phosphate (AA2P), an ascorbic acid derivative of vitamin C, was added in HSC culturing by imitating oxygen conditions which BMHSC experienced in peripheral blood stem cell transplantation. The protective effect of above-mentioned culture methods on the biologic functions of BMHSC was evaluated by vitro amplification assay, committed division assay, reactive oxygen species (ROS) measurement, CD34(+) HSC engraftment. The results showed that the ROS level in HSC from in vitro cultures was much higher than that freshly separated BMHSC, and the amplified AC133(+)CD34(+) HSC, BFU-E, CFU-GM, CFU-GEMM colonies, migration rate and severe combined immunodeficiency (SCID)-repopulating cells (SRC) were all much more than HSC cultured without AA2P. It is concluded that antioxidant intervention may be an effective methods for protecting the biological function of PBHSC and improving the therapeutic effect of PBHSCT.

Influence of reactive oxygen species on mouse bone marrow hematopoietic stem cell apoptosis / 中国实验血液学杂志

Objective of this study was to investigate the mechanism of the biological function damage resulting from increased ROS in peripheral blood stem cells during peripheral blood stem cell transplantation. Bone marrow hematopoietic stem cells (BMHSC) were cultured at the oxygen concentration imitated according to the bone marrow oxygen concentration (5% O2) including mean venous oxygen concentration (12% O2), mean arterial oxygen concentration (20% O2). The ROS level in BMHSC was detected by using fluorescent probe, the percentage of BM-HSC in cell cycle was determined by flow cytometry, the apoptosis rate was assayed by Annexin V/PI double staining, the expression levels of ATM gene and P21 protein were measured by PCR and Western respectively. The results showed that as compared with control group (5% O2), the ROS levels were lower, the percentage of cells in G1, S,G2/M phase increased (P < 0.01), the apoptosis rate of cells obviously increased (P < 0.01), the expression level of ATM gene obviously decreased (P < 0.01), while the expression level of P21 protein significantly was enhanced (P < 0.01) in 12% O2, 20% O2 and 5%-12%-20% O2 groups. It is concluded that ROS results in the apoptosis of BMHSC through inhibiting the expression of ATM gene and activating P21 protein.

Correlation between reactive oxygen species of cryopreserved peripheral blood mononuclear cells and expression of homing adhesion molecules on peripheral blood hematopoietic stem/progenitor cells / 中国实验血液学杂志

This study was purposed to detect the level of reactive oxygen species (ROS) in cryopreserved peripheral blood mononuclear cells (PBMNC) and the expression of homing molecules on peripheral blood hematopoietic stem/progenitor cells, and to analyze the correlation between ROS level and the expression of homing molecules. The survival percentage of PBMNC was determined by trypan blue exclusion rate. The expression of antigens on peripheral blood hematopoietic stem/progenitor cells, such as CD34, CD133 and some related homing molecules (VLA4, CXCR4 and CD44) were detected by flow cytometry. The correlation of the ROS levels with the expression of homing molecules was evaluated by the correlation coefficient. The results showed that the survival rate of PBMNC was gradually reduced along with prolongation of cryopreserved time, and there was a significant difference in the survival percentage of cryopreserved PBMNC between experimental group frozen for 3, 6, 9, 12 months and control group (P < 0.05). The expression of marked antigen CD34 and CD133, and homing adhesive molecules of CD44, VLA4 and CXCR4 declined with the extension of frozen time, and there was significant statistical difference (P < 0.05) between experimental group cryopreserved for a year and control group. The level of ROS in PBMNC gradually increased along with the prolongation of cryopreserved time, and there was significant statistical difference (P < 0.05) between experimental group freezing-stored for 6, 9 and 12 months and control group. The correlation coefficients of ROS level and expression percentage CD34(+) VLA4(+), CD34(+) CXCR4(+), CD34(+) CD44(+) PBMNC were -0.50, -0.457, -0.465, respectively. It is concluded that ROS level in PBMNC increases significantly with the prolonged cryopreservation time, especially for more than 6 months. There is a significant negative correlation between the ROS level of PBMNC and the expression rate of homing molecules. Higher level of ROS may be one of the reasons for the reduction of homing capability in peripheral blood stem/progenitor cells after cryopreservation.