Red cell transfusion in medicine: Future challenges

Many side-effects of red blood cell transfusion have been described. They include iron-overload, as well as allo- and autoantibody formation against red cells. During storage, erythrocytes undergo complex structural and biochemical changes. It has been suggested that accelerated and/or aberrant forms of the physiological erythrocyte aging process underlie the red cell storage lesion. This storage lesion may contribute to side-effects of transfusion as endothelial damage by release of internal erythrocyte constituents, (pro)inflammatory consequences, hampered microcirculation and oxygen delivery. Understanding the process that determines the fate of red blood cells after transfusion may contribute to the prevention of side-effects after red blood cell transfusion. This should be the focus of research on red blood cell transfusion in clinical transfusion medicine.     

Lack of effect of ouabain on sodium transport across the rat placenta

The umbilical vascular bed of the rat placenta was perfused in situ. Ouabain (10^–4M) in the perfusion fluid had no effect on the unidirectional flux of Na⁺ from the maternal (electrically negative) to the foetal (electrically positive) side of the placenta, or on the transplacental potential difference. This was taken to indicate that there is no significant active transport of Na⁺ across the placenta of the rat.     

米非司酮终止中期妊娠时胎盘循环与超微结构的变化

观察３０例妊娠１６～２４周需终止妊娠者服用米非司酮前后子宫动脉和脐动脉血流速度波型的变化，并用电镜观察了５例胎盘微血管的改变。结果：服用米非司酮后，子宫动脉阻力指数（ＲＩ）和Ｓ／Ｄ比值及脐动脉的Ｓ／Ｄ比值较用药前明显增高，胎盘微血管壁有损伤性表现。提示：子宫胎盘循环动力学的变化及胎盘微血管的损伤可能是米非司酮终止妊娠的重要环节。     

大鼠肝移植排斥反应期一氧化氮合酶的动力学变化

目的 探讨供体特异性输血（DST）预处理后大鼠同种肝移植物一氧化氮合酶（NOS）的动力学变化。方法 观察同基因肝移植（Ⅰ组），同种肝移植（Ⅱ组），DST预处理的同种肝移植（Ⅲ组）术后NOS的表型及亚硝酸盐/硝酸盐，细胞因子的动态变化。结果 Ⅱ组血中亚硝酸盐/硝酸盐，INF-α，TNF-α浓度明显增高，免疫组化显示，Ⅱ组移植物中macNOS^ 及ED1^ ,ED2^ 细胞数明显增多，Northern blot分析，Ⅲ组移植物中IL-10和TGF-BmRNA呈高水平表达；Ⅱ组移植物的iNOS和IL-12mRNA水平明显高于其他组。结论 DST预处理的移植物处于免疫无应答状态，NOS被抑制与TH2及TH3类细胞因子高表达有关。     

Molecular and serological evaluation of surface antigen negative hepatitis B virus infection in blood donors from Venezuela

Surface antigen negative hepatitis B virus (HBV) infection was evaluated in Venezuela, by molecular characterization of blood samples positive for antibodies to core antigen (anti-HBc) and negative for surface antigen (HBsAg) in blood donors (residual infections). HBV DNA was found in 11/258 samples (4.3%), and was significantly associated with high levels of anti-HBc antibodies (>25 UI/ml, P < 0.05), while no correlation was found between the presence of HBV DNA and the levels of anti-HBs. Synonymous and non-synonymous mutations were found in the HBV surface region (but not vaccine escape mutants) and in the precore/core region (precore mutants in 2/7 samples and 33-45 bp deletions near the N-terminal core region in 4/19 samples). While HBV genotype F prevails among HBsAg positive samples from blood donors in Venezuela, residual infection isolates were mainly genotypes A and D. Phylogenetic analysis of viral surface and core region revealed discrepancies in genotype designation in 6/9 samples, suggesting the presence of mixed infection or recombination. In conclusion, HBV residual infection in Venezuela does not seem to be frequently observed in HBV genotype F. This type of infection is frequently associated with variants exhibiting mutations in the surface gene that might be affecting the correct recognition by commercial tests, with precore mutants and with core internal deletions. These variants do not seem to cause severe liver disease, and on the contrary, were found circulating at low viremia.     

Influence of FK506 and cyclosporin A on alloantibody production and lymphocyte activation following blood transfusion.

The effect of administration of cyclosporin A (CyA) or the novel macrolide FK506 was investigated in AO rats given DA blood transfusions. CyA (10 mg/kg, orally) or FK506 (1 mg/kg, intramuscularly) administered for 14 days from the time of transfusion effectively inhibited primary anti-MHC class I alloantibody production. This profound inhibitory effect persisted throughout the 2-month investigation period, with little increase in 'secondary' alloantibody production following a challenge injection 28 days after drug withdrawal. Flow cytometric analysis revealed no significant differences in the absolute numbers of W3/25+ (CD4+), OX-8+ (CD8+) or OX-12+ (B lymphocytes), in either the spleen or peripheral blood of transfused compared with normal, untreated animals. However, a small but significant increase in the numbers of splenocytes expressing the activation marker OX-40 (activated CD4+ cells) was observed in transfused animals. Either CyA or FK506 significantly reduced the number of cells expressing OX-39 (interleukin-2 receptors) and OX-40. Treatment of transfused animals with CyA, but not FK506 for 14 days resulted in minor, transient reduction in peripheral blood OX-19+ and W3/25+ cells, while 'sparing' the OX-8+ cells; these changes were not observed in spleens. In contrast, the absolute spleen cell numbers of OX-19+, W3/25+ and OX-8+ cells were significantly reduced in transfused animals given 14 days of FK506 treatment, while the corresponding blood cells were unaffected. Induction of splenic lymphoproliferative responses by the T cell mitogen concanavalin A remained normal in animals receiving transfusion alone or with CyA. In contrast, profound inhibition of mitogenic responses was observed in FK506-treated animals and this inhibitory effect declined gradually following drug withdrawal. No non-specific suppressor cell activity was detected in the spleens of rats given transfusion alone or in CyA or FK506-treated transfused animals.     

Intraplacental choriocarcinoma with fetomaternal transfusion

Intraplacental choriocarcinoma is very rare, and is usually found only after maternal and fetal metastatic disease is identified. The purpose of this case report is to review the incidence and findings of intraplacental choriocarcinoma. A term placenta was investigated because the newborn was born with severe anemia (Hb 3.0 g/dL). A 2 cm nodule was noted on the surface of the amniotic membrane and grossly resembled an infarction. The tumor was examined microscopically with immunohistochemical staining for the alpha- and beta-human chorionic gonadotropin (alpha-hCG, beta-hCG) subunits, human placental lactogen (hPL) and Ki-67. Microscopically, the tumor consisted of necrotic areas with proliferation of atypical trophoblastic cells and destruction of the villi and capillaries. The cells were positive for the alpha-hCG, beta-hCG subunits, hPL and Ki-67, consistent with intraplacental choriocarcinoma. The mother and newborn were investigated for the presence of metastatic disease. Computed tomography scans and magnetic resonance imaging of the mother and infant were negative for metastatic disease. Choriocarcinoma, limited only to the placenta with no evidence of metastatic disease is very rare. Primary intraplacental choriocarcinoma may frequently be overlooked or missed, and choriocarcinoma may possibly arise in the placenta more often than in retained or persistent trophoblast following pregnancy.     

早、中、晚孕期胎盘因子体外抗HIV-1的研究

目的 探讨早、中、晚孕期胎盘因子(PF)体外抗人免疫缺陷病毒-1(HIV-1)及在HIV-1垂直传播中的作用.方法 荧光染料Calcien-AM标记的H9/HIV-1ⅢB分别与早、中、晚孕期不同稀释浓度的PF作用后,与MT2细胞培养,荧光显微镜下观察合胞休的形成;用HIV-1ⅢB感染MT2细胞,并分别与早、中、晚孕期不同稀释浓度的PF作用后,用MTT法检测HIV-1感染细胞的存活率,用ELISA方法检测细胞培养上清中p24抗原水平.结果 各孕期PF并不能抑制MT2和H9/HIV-1ⅢB细胞的融合,但可以增加HIV-1感染细胞的存活率及减少HIV-1 p24抗原的表达,且效应以早孕期PF最大,中孕期PF其次晚孕期PF最小,并与剂量呈正相关.结论 PF在体外具有抗HIV-I的作用,并呈现孕期和剂量相关性,可能在阻断HIV-1垂直传播中具有一定作用.     

彩色多普勒超声诊断胎盘绒毛膜血管瘤

目的探讨彩色多普勒超声(CDFI)对胎盘绒毛膜血管瘤的诊断价值及其临床意义。方法回顾性分析了6例胎盘绒毛膜血管瘤的CDFI表现及妊娠结果。结果6例患者肿瘤均为单发,2例瘤体直径>5.0 cm,有羊水过多,新生儿窒息等不良并发症。4例直径<5.0 cm,随访至分娩,未发生明显并发症。结论CDFI是产前诊断胎盘血管瘤惟一有效的辅助手段,对于瘤体较大,CDFI的监测和随诊对临床具有重要的指导意义。     

Quality validation of platelets obtained from the Haemonetics and Trima Accel automated blood-collection systems

BackgroundPlatelet transfusion is required to treat haemo-oncology or trauma patients. Platelet apheresis (PA) performed with apheresis equipment has increased rapidly in recent years. Leucocyte-reduced platelet apheresis (LRPA) can reduce the risk of platelet refractoriness and febrile nonhemolytic transfusion reactions (FNHTRs) for transfusion. Accordingly, this study aimed to investigate and compare the platelet metabolic and functional responses between PA performed with Haemonetics and LRPA performed with Trima Accel cell separator.MethodsThe qualities of platelets collected through PA and LRPA were evaluated in terms of visual appearance, morphology, platelet-aggregation changes, metabolic activities, and bacterium-screening test during 5-day storage. Statistical analyses included two-sample t-test and generalised estimating equation(GEE) method.ResultsDuring 5-day storage in LRPA, residual leucocytes were all <1.0×10⁶, and the parameters of platelet function were as follows: platelet aggregated to agonists such as adenosine 5′-diphosphate (ADP) and collagen, and the extent of shape change and pO₂ showed no statistically significant difference between PA and LRPA. The hypotonic shock reaction (HSR) on days 0, 1, and 3 were significantly higher in LRPA than in PA (71.78±6.92 vs. 64.10±7.42; P=0.002; 71.53±8.98 vs. 62.96±9.84; P=0.007; 68.05±7.28 vs. 57.76±6.80; P<0.0001, respectively). Values of mean platelet volume (MPV) were statistically larger in PA than in LRPA on days 0, 1, and 3. On day 5, the swirling score was higher in LRPA than in PA. The mean lactate levels had no statistically significant difference between PA and LRPA. Moreover, no growth was observed through bacterium-screening test conducted on 40 samples.ConclusionComparison of LRPA and PA products collected from the Trima Accel and Haemonetics automated blood-collection systems, respectively, revealed that both products possessed good platelet qualities even though additional processes are needed to reduce leucocytes. Furthermore, investigating the outcomes of other apheresis instruments with focus on the safety of donors, products, and recipients is necessary.