| Popis: |
Exosomes and other extracellular vesicles traffic a variety of protein and nucleic acid cargo throughout the body. Immune cells especially utilize these vesicles for communication, and they are being studied in clinical settings for their potential to act as disease markers, but also to serve as drug delivery systems. In animal science, a large part of the research around exosomes has centered around their presence in milk, as well as their bioavailability and potential impact for the neonate and for humans; milk-derived exosomes are enriched with immune-related proteins and microRNA that may relate to maternal health, mammary function, or neonate development. We sequenced miRNA isolated from colostrum of dairy cows predicted to feature either moderate or high degree of immune suppression, but found minimal differences (2 differentially expressed miRNA of 343 miRNA analyzed) between the two groups. Immune suppression exhibited during early lactation may also be related to altered exosome-mediated communication between immune cells. We studied the ability of bovine exosomes to alter immune responses of primary bovine monocyte-derived macrophages and found that exosomes alone or in combination with LPS were able to stimulate cytokine production to a greater extent than LPS alone. The ability of exosomes to transport cytokine, bioactive lipid, and regulatory RNA cargo suggests potential involvement in transition cow health. Altered exosome content and function have been associated with uterine infection, mastitis, and metabolic dysfunction; future studies with exosome signaling may help clarify the complexities of transition cow immune function and point to strategies to support immunity. |
