Toll-like Receptor Expression Patterns in the Female Reproductive Tract of Sheep

Area of Science:

• Reproductive immunology
• Innate immunity in mammals

Background:

• Toll-like receptors (TLRs) are key innate immune sensors.
• The role of TLRs in mammalian reproduction is not well understood.

Purpose of the Study:

• Investigate TLR1-9 expression and localization in the Hu sheep reproductive system.
• Examine the association between TLRs and sheep prolificacy.

Main Methods:

• Screening of TLR1-9 expression in oviduct, uterus, and ovary.
• Immunohistochemistry for TLR2, TLR6, and TLR7 localization.
• Comparative analysis between high-prolificacy (HP) and low-prolificacy (LP) sheep.

Main Results:

• TLRs are expressed throughout the oviduct, uterus, and ovary.
• TLR2, TLR6, and TLR7 localized in epithelial and muscle tissues, and ovarian follicles.
• HP sheep showed lower TLR2, higher TLR6, and lower TLR7 expression in ovaries compared to LP sheep.
• TLR7 associated with granulosa cell apoptosis, suggesting a role in follicular development.

Conclusions:

• TLRs play a dual role in sheep, acting as immune sentinels and reproductive regulators.
• TLR2, TLR6, and TLR7 are implicated in influencing ovine fertility and prolificacy.
• Innate immunity pathways are linked to reproductive success in sheep.