Detection of the anti-SARS-coronavirus specific antibody levels in 156 SARS patients / 中国实验血液学杂志

The objective of this study was to explore the development of IgG and IgM against SARS CoV and characteristics of changes of antibody titers in patients with severe acute respiratory syndrome (SARS) and to search the opportunity for collecting specific anti-serum from convalescent patients with SARS. The anti-SARS-coronavirus specific antibody levels in 156 SARS patients were measured with ELISA. The results showed that the total positive rates of IgG and IgM were 75.6% and 41.7% respectively, and the negative rate of both IgG and IgM was 23.7%. The average titers of IgG and IgM antibody in positive samples were 18.23 +/- 24.72 and 2.18 +/- 1.13, respectively. There was no significant correlation between the titers of IgG/IgM and sex, age, course of diseases and duration of body temperature recovery. It was concluded that not all SARS patients could produce the anti-SARS-coronavirus specific antibody. The titers of the anti-body are diversified even if the antibodies have been emerged in them. In order to obtain effective anti-serum, the titers of antibody must be tested just before collection of convalescent serum, and it ensures the therapeutic effect and provides a measurable index for clinical transfusion.

Effects of leukocyte elimination before storage on quality of red blood cell concentration / 中国实验血液学杂志

The objective of this study was to explore the possible effects of leukocyte elimination by filteration before storage on the quality of red blood cell concentrations (RCC) that prepared through two procedures. Eight units of red blood cell concentrations derived from whole blood after plasma separated (RCC1) and eight units of red blood cell concentrations derived from whole blood after platelet-rich plasma separated (RCC2) were divided randomly into filtered group and control group respectively. The RCC of filtered group were filtered by leukocyte deplete filter before storage. The control group didn't have any other treatments. These two groups were stored for five weeks at 4 degrees C according to AABB standard. Mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), mean corpuscular hemoglobin concentration (MCHC) and plasma concentration of K(+) and lactate dehydrogenase (LDH), free hemoglobin (FHb), adenosine triphosphate (ATP) of red blood cell of all RCC were evaluated weekly, and bacteria contamination of all RCC was also detected after five weeks of storage. The results showed that there was no difference of MCV, MCH and MCHC and ATP level of red blood cell in all RCC of two groups, the ATP of red blood cell was lower than the control group on week 4 and 5. The average concentration of K(+) of the filtered group was less than the control group. The differences are significant except that of RCC1 stored till the third week. The plasma LDH concentration of filtered group was less than the control group, and the differences were exacerbate during the storing time prolonged. FHb release in the filtered group of RCC2 was significant less than that of control, but no significant difference was found between the two groups of RCC1. It was concluded that leukocyte elimination by filter before storage could be benefit to RCC preservation.

Thermometry of intracellular ice crystal formation in cryopreserved platelets / 中国实验血液学杂志

The temperature of platelet intracellular ice crystal formation (IIF) is one of the most important physical parameters to instruct platelet cryopreservation. In this study, the range of temperatures for platelet IIF was measured by means of biological and physical methods. All platelet samples were graded cooling, and two samples of per 5 degrees C decrease were thawed by 2 different ways: 37 degrees C directly (T 37 degrees C) and 37 degrees C after keeping in liquid nitrogen (LN) for 2 hours. The phosphatidylserine (PS) positive rate, plasma lactate dehydrogenase (LDH) concentration and platelet aggregate rate were measured in all samples. The heat release graphs of platelets cryopreserved with or without 5% DMSO were also measured by differential scanning calorimeter (DSC). The results showed that the PS positive rates and aggregate rates in platelets and plasma LDH concentrations gradually increased in T 37 degrees C group and decreased in LN group until the arrival of -35 degrees C, and then there were no further changes of the 3 parameters. A small second heat release peak was detected at about -35 degrees C in the platelet samples cryopreserved without DMSO. It is concluded that the temperature of intracellular ice crystal formation in platelet is from -30 to -40 degrees C (-35 degrees ).

Comparison of leucocyte-reduced platelet concentrates produced with spectra version 5.1 and version 7.0 blood cell separators / 中国实验血液学杂志

In the present study, the performance of a new blood cell separator (COBE Spectra LRS Turbo Version 7.0) and that of the previous version LRS version 5.1 in the collection efficiency (CE), collection rate and residual white blood cells during platelet collection from donors were compared. 232 units of platelet concentrates (n = 232) were evaluated and 163 units were collected with the Spectra LRS version 5.1 (Group A) and 69 units with the LRS turbo version 7.0 (Group B). Donor's blood cell counts and parameters, platelet yield, collection efficiency and residual leukocytes in platelet concentrates were analysed. Results showed that the platelet yield was higher in group B than that in group A: (2.90 +/- 1.1) x 10(11) versus (2.58 +/- 1.2) x 10(11), P < 0.001; residual WBCs were less than 5 x 10(6) in 99.4% of group A platelet concentrates and in 97.1% of group B platelet concentrates. Collection efficiency was higher in group B than in group A: 51.4 +/- 8.7 versus 43.6 +/- 6.3. A correlation between platelet count before collecting blood and platelet yield was observed in both groups. In conclusion, the Spectra LRS Turbo version 7.0 showed a higher platelet yield than that with LRS version 5.1. Higher platelet counts before collection allow a higher platelet yield.