PARTITIONING OF HEPETITIS C VIRUS DURING COHN-ONCLEY FRACTION OF PLASMA

由于对免疫球蛋白安全性的担忧， 丙型肝炎的传播，我们检查了丙型肝炎的分区 制备的血浆池酒精分离过程中的病毒(丙型肝炎病毒) 完全来自抗丙型肝炎病毒反应性捐赠。丙型肝炎病毒核糖核酸定量 通过套式聚合酶链式反应(PCR)在限制 稀释。一个聚合酶链式反应单位被任意定义为 可检测到扩增产物的丙型肝炎病毒核糖核酸。敏感度 用限制性稀释法测定丙型肝炎病毒核糖核酸的 一份已知含有106.6的传染性血浆(H株)样本的分析 黑猩猩感染剂量/毫升。在我们的检测中，该样本含有1.4倍 106个聚合酶链式反应单位/毫升的丙型肝炎病毒核糖核酸。因此，该聚合酶链式反应方法具有较高的灵敏度 可以与黑猩猩模型相媲美。当3073名捐献血浆的人 对其他可接受的献血者进行了抗-丙型肝炎病毒检测，186人重复检测 反应性和2,887例为阴性。由抗丙型肝炎病毒抗体制备的池 反应性捐赠含有1.4×105个聚合酶链式反应单位的丙型肝炎病毒RNA/毫升，而 由阴性供体制备的池含有1.6×103个聚合酶链式反应单位/毫升。 可以计算出，由所有3,073个单元组成的池将包含 1.0×104个聚合酶链式反应单位/毫升。因此，在这种情况下，抗-丙型肝炎病毒筛查 将血浆池的病毒载量降低6倍。100毫升 抗-丙型肝炎病毒反应池样本通过以下方法分离为免疫球蛋白 Cohn-Oncley程序，以及不同馏分的样品 进行了丙型肝炎病毒核糖核酸分析。大部分丙型肝炎病毒RNA存在于冷沉淀物和 在科恩组分I和III中，但在组分II中也检测到它，使用 用于免疫球蛋白G制剂。一种3.4%的免疫球蛋白溶液 该组分II含有30个PCRU/ml。分级过程 导致免疫球蛋白导致丙型肝炎病毒RNA的总体减少 4.7x104的系数。尽管在决赛中出现了丙型肝炎病毒RNA 产品并不一定意味着存在病毒，这项工作 提示免疫球蛋白相对于丙型肝炎病毒的安全性 传播并不完全是由于丙型肝炎病毒与 免疫球蛋白部分。

Because of concern about the safety of immunoglobulins with respect to transmission of hepatitis C, we examined the partitioning of hepatitis C virus (HCV) during alcohol fractionation of a plasma pool prepared exclusively from anti-HCV reactive donations. Quantitation of HCV RNA was accomplished by nested polymerase chain reaction (PCR) at limiting dilution. One PCR unit was arbitrarily defined as the minimum amount of HCV RNA from which an amplified product could be detected. The sensitivity of the PCR assay for HCV RNA was determined by performing limiting dilution analysis on a sample of infectious plasma (H strain) known to contain 106.6 chimpanzee infectious doses/ml. In our assay, this sample contained 1.4 x 106 PCR units of HCV RNA/ml. Thus, the PCR assay has a sensitivity comparable to the chimpanzee model. When 3,073 plasma donations from otherwise acceptable donors were tested for anti-HCV, 186 were repeatedly reactive and 2,887 were negative. A pool prepared from the anti-HCV reactive donations contained 1.4 x 105 PCR units of HCV RNA/ml, whereas a pool prepared from the negative donations contained 1.6 x 103 PCR units/ml. It can be calculated that a pool comprised of all 3,073 units would contain 1.0 x 104 PCR units/ ml. Thus, in this instance, anti-HCV screening decreased the viral load of the plasma pool by a factor of 6. A 100-ml sample of the anti-HCV reactive pool was fractionated to immune globulin by the Cohn-Oncley procedure, and samples of the various fractions were analyzed for HCV RNA. Most of the HCV RNA was found in cryoprecipitate and in Cohn fractions I and III, but it was also detected in fraction II, used for immunoglobulin G preparations. A 3.4% solution of IgG prepared from this fraction II contained 30 PCR units/ml. The fractionation process leading to immune globulin resulted in an overall reduction in HCV RNA by a factor of 4.7 x 104. Although the presence of HCV RNA in the final product does not necessarily imply the presence of virus, this work suggests that the safety of immune globulins with respect to HCV transmission is not due solely to partitioning of HCV away from the immunoglobulin fraction.