Kosaka Nobuyoshi, Izumi Hirohisa, Sekine Kazunori, Ochiya Takahiro
Section for Studies on Metastasis, National Cancer Center Research Institute, 1-1, Tsukiji 5-chome, Chuo-ku, Tokyo 104-0045, Japan.
Silence. 2010 Mar 1;1(1):7. doi: 10.1186/1758-907X-1-7.
Breast milk is a complex liquid that provides nutrition to the infant and facilitates the maturation of the infant's immune system. Recent studies indicated that microRNA (miRNA) exists in human body fluid. Because miRNAs are known to regulate various immune systems, we hypothesized that human breast milk contains miRNAs that may be important for the development of the infant's immune system.
We profiled miRNA expression in human breast milk and detected high expression levels of immune-related miRNAs in the first 6 months of lactation. Furthermore, these miRNA molecules are stable even in very acidic conditions, indicating that breast milk allows dietary intake of miRNAs by infants.
Our findings provide new insight into how breast milk can modulate the development of the infant's immune system. This study suggests the transfer of genetic material as miRNA from human to human occurs by means other than through sexual reproduction.
母乳是一种复杂的液体，为婴儿提供营养并促进婴儿免疫系统的成熟。最近的研究表明，微小RNA（miRNA）存在于人体体液中。由于已知miRNA可调节各种免疫系统，我们推测人母乳中含有可能对婴儿免疫系统发育很重要的miRNA。
我们分析了人母乳中miRNA的表达，并在哺乳期的前6个月检测到免疫相关miRNA的高表达水平。此外，这些miRNA分子即使在非常酸性的条件下也很稳定，这表明母乳允许婴儿通过饮食摄入miRNA。
我们的研究结果为母乳如何调节婴儿免疫系统的发育提供了新的见解。这项研究表明，作为miRNA的遗传物质在人与人之间的转移是通过性繁殖以外的方式发生的。
