Macrophages regulate gastrointestinal motility through complement component 1q
- The University of Texas Southwestern Medical Center, United States
Abstract
Peristaltic movement of the intestine propels food down the length of the gastrointestinal tract to promote nutrient absorption. Interactions between intestinal macrophages and the enteric nervous system regulate gastrointestinal motility, yet we have an incomplete understanding of the molecular mediators of this crosstalk. Here we identify complement component 1q (C1q) as a macrophage product that regulates gut motility. Macrophages were the predominant source of C1q in the mouse intestine and most extraintestinal tissues. Although C1q mediates complement-mediated killing of bacteria in the bloodstream, we found that C1q was not essential for immune defense of the intestine. Instead, C1q-expressing macrophages were located in the intestinal submucosal and myenteric plexuses where they closely associated with enteric neurons and expressed surface markers characteristic of nerve-adjacent macrophages in other tissues. Mice with a macrophage-specific deletion of C1qa showed changes in enteric neuronal gene expression, increased neurogenic activity of peristalsis, and accelerated intestinal transit. Our findings identify C1q as a key regulator of gastrointestinal motility and provide enhanced insight into the crosstalk between macrophages and the enteric nervous system.
Data availability
16S rRNA gene sequencing data (Figure 3D) and RNA sequencing data (Figure 6A and B; Figure 1 - figure supplement 1; Figure 6 - figure supplement 3) are available from the Sequence Read Archive under BioProject ID PRJNA793870. All mouse strains used are available commercially.
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Macrophages control gastrointestinal motility through complement component 1qSequence Read Archive; PRJNA793870.
Article and author information
Author details
Alexander A Crofts
Funding
National Institutes of Health (R01 DK070855)
- Lora V Hooper
Welch Foundation Grant (I-1874)
- Lora V Hooper
Howard Hughes Medical Institute (N/A)
- Lora V Hooper
National Institutes of Health (T32 AI005284)
- Mihir Pendse
National Institutes of Health (T32 AI005284)
- Alexander A Crofts
National Institutes of Health (F32 DK132913)
- Alexander A Crofts
National Institutes of Health (F31 DK126391)
- Eugene Koo
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: This study was performed in strict accordance with the recommendations in the Guide for the Care and Use of Laboratory Animals of the National Institutes of Health. All of the animals were handled according to approved institutional animal care and use committee (IACUC) protocols (protocol #2015-101212) of the University of Texas Southwestern Medical Center.
Copyright
© 2023, Pendse et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Macrophages regulate gastrointestinal motility through complement component 1q
eLife 12:e78558.
https://doi.org/10.7554/eLife.78558
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Preeclampsia (PE), a major cause of maternal and perinatal mortality with highly heterogeneous causes and symptoms, is usually complicated by gestational diabetes mellitus (GDM). However, a comprehensive understanding of the immune microenvironment in the placenta of PE and the differences between PE and GDM is still lacking. In this study, cytometry by time of flight indicated that the frequencies of memory-like Th17 cells (CD45RA−CCR7+IL-17A+CD4+), memory-like CD8+ T cells (CD38+CXCR3−CCR7+Helios−CD127−CD8+) and pro-inflam Macs (CD206−CD163−CD38midCD107alowCD86midHLA-DRmidCD14+) were increased, while the frequencies of anti-inflam Macs (CD206+CD163−CD86midCD33+HLA-DR+CD14+) and granulocyte myeloid-derived suppressor cells (gMDSCs, CD11b+CD15hiHLA-DRlow) were decreased in the placenta of PE compared with that of normal pregnancy (NP), but not in that of GDM or GDM&PE. The pro-inflam Macs were positively correlated with memory-like Th17 cells and memory-like CD8+ T cells but negatively correlated with gMDSCs. Single-cell RNA sequencing revealed that transferring the F4/80+CD206− pro-inflam Macs with a Folr2+Ccl7+Ccl8+C1qa+C1qb+C1qc+ phenotype from the uterus of PE mice to normal pregnant mice induced the production of memory-like IL-17a+Rora+Il1r1+TNF+Cxcr6+S100a4+CD44+ Th17 cells via IGF1–IGF1R, which contributed to the development and recurrence of PE. Pro-inflam Macs also induced the production of memory-like CD8+ T cells but inhibited the production of Ly6g+S100a8+S100a9+Retnlg+Wfdc21+ gMDSCs at the maternal–fetal interface, leading to PE-like symptoms in mice. In conclusion, this study revealed the PE-specific immune cell network, which was regulated by pro-inflam Macs, providing new ideas about the pathogenesis of PE.
