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Objective To evaluate the storage performance of storage bags for apheresis platelets produced by Shandong Weigao Group Medical Polymer Co .,Ltd ( experimental bags ) with Trima set platelet storage bags produced by the U .S. Gambro BCT as the control .Method One unit of apheresis platelets was divided into two equal parts , added to control blood bags and experimental blood bags respectively .All samples were stored at ( 22 ±2 )℃ with consecutive oscillation . The platelets′count, mean volume, aggregate activity (ADP, THR), pH, glucose, lactate concentration, lactate dehydro-genase concentration , hypotonic shock reaction , expression of CD62P and phosphatidyl serine on surface of cell membrane were detected at 0,3,5 and 7 d respectively.Results There was no significant difference in platelet quality after five days of storage between the experimental group and the control group (t-test, P>0.05).Conclusion Two types of platelet stor-age blood bags have similar storage performance for apheresis platelets .
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Objective To improve the processing protocol of the frozen erythrocyte ( RBC) washing machine of the dialysis type to enhance its efficiency of treating the 2 U frozen RBCs .Methods The frozen RBC washing machine for dialysis was used to deglycerolize the 2 U frozen RBCs after thawing .Measures including adjustment of the Pump speed , washing buffer adding and solution osmolarity were taken to decrease the processing time .Hemoglobin(Hb) content, Hb recovery, residual glycerol, free Hb content, deforming ability, and apoptosis of the deglycerolized RBCs were assessed to evaluate the efficiency of the improved protocol .Results As for the cells processed respectively by the previous and improved protocols, contents of Hb were (35.03 ±4.20) g and (53.82 ±2.08) g, respectively; Hb recoveries were (61.10 ±8.46)% and (80.22 ±3.73)%,respectively.Osmolarities representing residual glycerol were (307.00 ± 14.50)mOsm and (322.00 ±29.00)mOsm.Free Hb values were (0.74 ±0.04) and (0.80 ±0.08)g/L.The processing time was (1.64 ±0.31) and (1.04 ±0.16) h,respectively.There were significant differences in Hb content , Hb recovery, and deforming ability between the cells processed by the two protocols respectively .However , there were no significant changes in glycerol contents , free Hb, and apoptosis extent between the cells processed by the two protocols .Conclusion The innovated protocol can improve the quality of washed frozen RBCs , decrease the processing time and enhance the efficiency of the machine.
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Objective To improve the protocols of red blood cells ( RBCs) processing devices ( automatic medical RBC centrifuge, type:BBS926).Methods RBCs separated from 400 ml of whole blood collected from healthy donors were frozen at -80℃.After thawing , the cells were processed by the washing device .Based on the original protocol ( protocol 1), a modified protocol (protocol 2) was established and used to evaluate the quality of the frozen RBCs .In the test group (protocol 2), the amount of washing buffers and the washing steps were revised to form the optimized protocol .RBCs processed with the two protocols were evaluated by different assays .Results The indexes from the standards for frozen-thawed RBCs: the amount of hemoglobin ( Hb) of RBCs from protocol 1 and protocol 2 was 37.55 ±3.58 and 42.18 ±3.35 g(P0.05);the residual amount of white blood cells (WBCs) was (1.90 ±0.99) ×107 and (1.92 ±1.04) ×107(P>0.05);The osmolarities were 334 ±8.03 mOsm and 327 ±9.06 mOsm(P>0.05);both the bacteria and fungi tests were negative for the RBCs processed with the two protocols .Among other indexes ,the hemolysis rate for RBCs from protocol 1 and protocol 2 was (12.44 ±8.24)%and (12.02 ±5.78)%(P>0.05), the deformation index was 21.40 ±1.41 and 21.42 ±1.45 (P>0.05), the RBC recovery was(72.02 ±3.70)%and (77.18 ±5.58)%(P0.05),and the processing time was (79.00 ±0.71)min and (79.60 ±0.55)min (P>0.05).Conclusion The RBCs processed by the two protocols meet the national standards for frozen-thaw RBCs.Hb amounts and cell recoveries of the RBCs are enhanced by treatment with protocol 2.Protocol 2 proves to be better than protocol 1.
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Objective Recent findings indicate that the serological and biochemical characteristics of porcine erythrocytes share many similarities with human red blood cell (hRBC). Scientists believed that humanized porcine red blood cells (pRBC) could be used as one alternative source for human blood transfusion. Methods In order to eliminate ?Gal antigen and non-?Gal on the surface of pRBC, recombinant soybean ?-Galactosidase (rS?-GalE) constructed by our lab was used to remove terminal ?Gal residues from ?Gal antigen, and mPEG-BTC was used to camouflage non-?Gal xenoantigen on the surface of pRBC. Results The carbohydrate structures of ?Gal xenoantigen of pRBC treated with rS?-GalE were completely modified. The antigenic determinants of ?Gal and non-?Gal xenoantigen on the surface of pRBC were successfully camouflaged through mPEG-BTC modification. But this modification needed higher concentration of mPEG-BTC which could cause slight structure damage. Considering this, with combination of ?Gal xenoantigen conversion by rS?-GalE and chemical camouflage of non-?Gal xenoantigen with lower concentration of mPEG-BTC, the antigenic determinants of pRBC were attenuated and hemagglutination were diminished.Conclusion The morphology, structures, functions and deformability of pRBC modified with rS?-GalE, mPEG-BTC and rS?-GalE+ mPEG-BTC were normal.
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Objective To observe the chemical camouflage effects of methoxy polyethylene glycol(mPEG) on like human B antigens on Rhesus monkey red blood cell(rRBC) and to study the safety of transfusion with mPEG modified monkey RBC(mPEG rRBC).Methods rRBC were modified with 3mg/ml mPEG. The rRBC blood group and the effects of mPEG modification on blood conversion were assayed by absorption and elution methods.The structural and functional changes of mPEG rRBC were also tested.The survival fraction of mPEG modified like B rRBC in like A recipient monkey were examined by flow cytometry.The transfusion effects of mPEG modified rRBC on recipient's blood and urine were also observed.Results mPEG have been covalently bound to the surface of Rhesus monkey RBC (like human B blood group),mPEG could cover rRBC like B antigen.Transfusion of mPEG modified like B rRBC to like A Rhesus monkey had no harmful effects on the recipient.Conclusion The present study suggests that transfusion of mPEG modified RBC could be safety in experimental animals