Klein F, Valkenburg H A, van Zwet T L, Lafeber G J
Immunology. 1966 Jan;10(1):87-98.
Using a sensitive modification of the latex fixation test it is possible to detect a small agglutinating effect in about 60 per cent of normal human sera, after these have been heated for 30 minutes at 56°. This was shown to be caused by an IgM globulin with the properties of a rheumatoid factor. The factor is able to react with human IgG globulin and may represent an antibody to the IgG part of circulating antigen—antibody complexes. The heat treatment probably inactivates an inhibitor of the latex fixation reaction. In addition all normal human sera give an agglutination reaction with IgG coated latex at incubation temperatures of 37° or lower. It was shown that these reactions are caused by a thermolabile, non-reducible component with a sedimentation constant of about 10. This component is probably identical with the complement component C'. The agglutinating activity was found in the α—β region after electrophoresis of untreated serum, but in the slow γ region after treatment of the serum with EDTA. This kind of agglutination may cause false positive reactions in latex tests which are carried out at 37° or less.
采用乳胶凝集试验的一种灵敏改良方法，可在约60% 的正常人血清中检测到微弱的凝集作用，这些血清在56℃加热30分钟后即可出现此现象。已证实这是由具有类风湿因子特性的IgM球蛋白引起的。该因子能够与人IgG球蛋白发生反应，可能代表针对循环抗原 - 抗体复合物中IgG部分的一种抗体。热处理可能使乳胶凝集反应的一种抑制剂失活。此外，所有正常人血清在37℃或更低的孵育温度下与IgG包被的乳胶都会发生凝集反应。结果表明，这些反应是由一种沉降常数约为10的热不稳定、不可还原的成分引起的。该成分可能与补体成分C' 相同。未经处理的血清电泳后，凝集活性出现在α - β区，但血清经EDTA处理后，凝集活性出现在慢γ区。这种凝集可能会在37℃或更低温度下进行的乳胶试验中引起假阳性反应。
