How gut microbes and the immune protein C3a shape adult bone health
Official title: Role of Complement in Commensal Microbiota Actions Regulating Sketal Maturation
Funded at Ralph H Johnson VA Medical Center · NIH-11129716 · Data updated 2026-11-12
This work explores whether common gut bacteria and an immune protein called C3a change bone growth and strength in adults.
Quick facts
| Grant type | NIH-funded research |
|---|---|
| Study type | NIH-funded research |
| Funding institution | Ralph H Johnson VA Medical Center NIH-funded |
| Lab location | 1 site (Charleston, United States) |
| Project start | July 1, 2022 |
| Project end | June 30, 2027 |
| Funding year | 2025 |
| NIH project number | 5IK2BX005813-04 |
| Project ID | NIH-11129716 on NIH RePORTER |
Who could benefit from this research
✓Could help
Adults aged 21 and older, particularly those with low bone density, osteoporosis, or age-related bone loss, would be most relevant to this research.
✕Less likely to help
Children and teenagers, and people whose bone problems are purely genetic or mechanical rather than immune- or gut-related, may not directly benefit.
What this research studies
The team will look at how everyday gut microbes talk to the immune system and influence bone-building and bone-resorbing cells after puberty. They focus on the complement pathway, especially the molecule C3a and its receptor C3aR on bone cells. The work uses lab experiments (animals and cell models) and measurements of bone density and immune signals, and may include comparisons across ages. Results could point to blood or gut markers that signal weaker bones or new ways to protect bone health.
Why it matters
Potential benefit: If successful, this could point to new ways to protect or improve bone density by targeting gut bacteria or complement signaling.
How similar studies have gone: Prior work shows gut microbes can affect bone and that complement influences inflammation, but using C3a/C3aR as the link between microbiota and bone is a relatively new approach.
Where this research is happening
-
Ralph H Johnson VA Medical Center
Charleston, United States Active
Researchers
- Principal investigator: Hathaway-Schrader, Jessica Diann — Ralph H Johnson VA Medical Center
- Study coordinator: Hathaway-Schrader, Jessica Diann
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About this research
- This is an active NIH-funded research project — typically early-stage science, not a clinical trial accepting patient enrollment.
- Some NIH-funded labs run parallel clinical studies or seek volunteers for related work. To check, contact the principal investigator or institution listed above.
- For full project details, budget, and progress reports, visit the official NIH RePORTER page.