The effects of endometrial epithelium-derived exosomes on the
recruitment and activation of T Lymphocytes in the uteri of dairy cows
- Hong An,
- Bofan Fu,
- Xinxin Yao,
- Hemin Ni,
- Yong Guo,
- Longfei Xiao,
- xiangguo wang
Abstract
As a common group-occurring disease, endometritis is caused by
endometrial cell injury and chronic inflammation of uteri infected by
pathogenic microorganisms, and leads to reproductive failure in dairy
cows. Changes in the immune response function of the uteri affect the
occurrence and development of endometritis. It was recently discovered
that exosomes act as a functional regulator secreted by a variety of
cells. However, its regulatory mechanism in the local immune response of
the uteri is still unclear. In this study, flow cytometry was adopted to
identify that the number of T lymphocytes in the uteri with endometritis
increased while the compositional proportion also changed, namely that
of Tc cell increased very significantly and that of Th and Treg cells
decreased very significantly. Moreover, the functional marker factor
Foxp3 of Treg cells was extremely significantly decreased, and the
functional marker factor of Th17 cells was significantly increased. The
mRNA expression of immune tolerance regulators PD1, CTLA4 and Galectin-1
in the group of Treg cells which were co-incubated with LPS-stimulated
endometrial epithelium-derived exosomes was very significantly lower
than in the group of Treg cells which were co-incubated with normal
EEC-derived exosomes. Furthermore, the protein expression of PD1, CTLA4,
Galectin-1, Foxp3, and IL-17 was consistent with the results in the Treg
cells co-incubated with different source exosomes in mice. Therefore, it
was demonstrated that endometrial epithelium-derived exosomes act as a
vital regulator of changes in the composition and function of T
lymphocyte subsets in the uterus of dairy cows.