Nagaki K, Tsuboi M, Matsumoto M, Kitamura H
J Clin Lab Immunol. 1986 Nov;21(3):141-6.
C1 was removed from human serum by polyethylene glycol (PEG) precipitation and the supernatant (C1 deficient serum, C1D) was used for assay of C1 hemolytic activity (C1D method). Serum concentration of PEG 6,000 ranging from 3.5-4% was determined to be suitable for preparation of C1D, but C1D prepared by PEG 4,000 were proved unsatisfactory for use. Oxidation of C1D by iodine treatment increased C1 activity by two-fold. The C1D method was comparable in sensitivity to the conventional method, and the correlation between the 2 methods was good (r = 0.94). The C1D method was shown to be a useful tool for the study of C1 activation, since the method specifically measured C1, but not C1 activity. A half-life (T1/2) of C1 activity in fluid phase at 37 degrees C was 20 min under physiologic conditions.
通过聚乙二醇（PEG）沉淀从人血清中去除C1，然后将上清液（C1缺陷血清，C1D）用于C1溶血活性测定（C1D法）。已确定6000的PEG血清浓度范围为3.5 - 4%适合制备C1D，但事实证明，用4000的PEG制备的C1D不能令人满意地使用。通过碘处理氧化C1D可使C1活性提高两倍。C1D法在灵敏度方面与传统方法相当，两种方法之间的相关性良好（r = 0.94）。由于该方法专门测量C1而非C1活性，因此C1D法被证明是研究C1激活的有用工具。在生理条件下，37摄氏度时液相中C1活性的半衰期（T1/2）为20分钟。
