PM2.5 exposure reprograms cell cycle dynamics in uterine immune cells at single-cell resolution

Area of Science:

• Reproductive immunology
• Environmental toxicology
• Cellular and molecular biology

Background:

• Fine particulate matter (PM2.5) exposure is linked to reproductive issues, but cellular mechanisms are unclear.
• Understanding immune cell responses in the uterus is crucial for reproductive health.

Purpose of the Study:

• To investigate the impact of PM2.5 on immune cell cycle dynamics in the mouse uterus.
• To identify specific immune cell populations affected and their cell cycle alterations.
• To explore gene expression changes related to cell cycle control in response to PM2.5.

Main Methods:

• Single-cell RNA sequencing was employed to analyze immune cells from mouse uteri.
• 9,000 cells were analyzed to identify distinct populations and cell cycle distributions.
• Differential gene expression analysis was performed to identify key regulatory genes.

Main Results:

• PM2.5 exposure significantly altered immune cell composition, reducing macrophages, NK cells, and granulocytes.
• Macrophages showed increased G1 phase and decreased G2M phase cells.
• NK cells exhibited modest cell cycle alterations, with identified regulatory genes like Cd81, Nrp1, and Vps37b.

Conclusions:

• PM2.5 exposure causes cell type-specific changes in uterine immune cell cycle progression.
• These findings provide mechanistic insights into how environmental pollution may cause reproductive dysfunction.