circulating miRNA的主要存在形式是Ago2-miRNA复合物还是囊泡相关?2011年PNAS的这篇文献“Argonaute2 complexes carry a population of
circulating microRNAs independent of vesicles in human plasma”认为是前者;2013发表在plos one的“The Major ity of MicroR NAs Detectable in Serum and saliva is concentrated in exosomes"认为是后者。现在有无较主流的说法?如果循环囊泡里的miRNA含量与non-vesicle circulating miRNA相比微乎其微,那其定量研究的意义何在?