Epidemiological study on SARS-CoV Ab among volunteer blood donors during SARS epidemic phase and non-SARS epidemic phase in Guangzhou / 中国输血杂志

Objective To investigate the situation and distribution of Severe Acute Respiratory Syndrome coronavirus (SARS-CoV) infection in volunteer blood donors during SARS epidemic phase and non-SARS epidemic phase in Guangzhou and provide scientific basis for developing preventive strategies. Methods Blood samples from volunteer donors were tested for SARS-CoV Ab by ELISA,and samples from 31 plasma donors recovered from SARS were tested as control. Donors with positive SARS-CoV Ab were further tested for SARS-CoV RNA by fluorescent polymerase chain reaction. Standardized questionnaires were adopted to conduct investigation by telephone on 20 donors with positive SARS-CoV Ab. Results SARS-CoV Ab was positive in 56 of 6120 volunteer blood donors and in 30 of 31 plasma donors recovered from SARS. The positive rates of SARS-CoV Ab were 0.92% and 96.77% respectively. In volunteer blood donors of SARS epidemic phase and non-SARS epidemic phase, the positive rates of SARS-CoV Ab were 0.91% and 0.92% respectively, and there was no significant difference between them. The mean S/CO and the titer of SARS-CoV Ab were 2.34 and ≤1∶2 respectively in the 56 volunteer blood donors, significantly lower than those of the 30 plasma donors recovered from SARS (S/CO 14.8,titer ≤1∶32). All donors with positive SARS-CoV Ab were negative for SARS-CoV RNA. Telephone consultation of 20 random blood donors with positive SARS-CoV Ab found that they were in good health and had not have close contact with SARS patients. Conclusion There is a low positive rate of SARS-CoV Ab among random blood donors in Guangzhou. Further studies are needed to find out whether those donors have been infected by SARS. It is also possible that those reactions were false positive, which might be caused by cross reactions. It is suggested that the present measures of SARS prevention could ensure blood safety.

Comparing plasma-depleted platelet concentrates with Regular PCs Produced from CS-3000 / 中国输血杂志

Obejective To assess the influence of apheresis and wash on platelet function and morphology.Methods To determine the count,size,distribution,agglutination,aggregation,GMP 140 & GPⅡb/Ⅲa of the platelet from the peripheral blood prior to apheresis and aphersed or washed platelets produced by CS 3000 plus.Results Both apheresed and washed platelets showed decreased PDW,PCT & MPV,but there were no statistical difference between groups.There were no difference in platelet adhesion,aggregation,CD 62p +,CD 41a +,and CD 62p +expression.Both apheresed and washed platelets showed increased CD 41a + expression,but there was no difference between apheresed and washed platelets.Conclusion Flow cytometry measurement of GMP 140 & GPⅡb/Ⅲa may be used for in vitro platelet function assessment.Although apherisis can induce mild platelet activation,platelets apheresed or washed by CS 3000 plus have reliable quality and can be used in a variety of clinical conditions.

Cloning and expression of a human monoclonal anti-D Fab fragment in E. coli with the use of bacteriophage vector / 中国病理生理杂志

AIM: To clone and express a human monoclonal anti-D Fab fragment in E. coli and make benefits for the expression of the whole immunoglobulin molecules of anti-D. METHODS: The gene of anti-D Fab fragment was cloned into the phagemid vector pComb3. After analyzing by PCR and restriction site analysis, the recombinant was expressed in E. coli and the expressed protein was analyzed by SDS-PAGE and ELISA. RESULTS: The result of SDS-PAGE confirmed that E.coli expressed a 48 kD protein. The ELISA result demonstrated that the cell culture supernatant reacted with Rh+ group O human erythrocytes, but was not recognized by Rh-group O human erythrocytes. CONCLUSION: Expressed Fab fragment has the antigenic specificity for human erythrocytes.