Gut immune protein C3 and protection from intestinal infections

Gut complement system: Induction and protection against enteric infection

['FUNDING_R01'] · HARVARD MEDICAL SCHOOL · NIH-11412408

This work looks at whether a protein made in the gut called C3 helps protect people—including young children—from infections that cause diarrhea such as C. difficile.

Quick facts

Phase['FUNDING_R01']
Study typeNih_funding
SexAll
SponsorHARVARD MEDICAL SCHOOL (nih funded)
Locations1 site (BOSTON, UNITED STATES)
Trial IDNIH-11412408 on ClinicalTrials.gov

What this research studies

From my perspective, the team will use specialized germ-free mouse models and change the gut bacteria to see how the gut makes C3. They will study individual gut cells using single-cell RNA sequencing and microscopic imaging to find which cells produce C3 and how levels change during infection. The researchers will compare those findings with samples from healthy people to confirm that the same gut complement system exists in humans. Overall, the approach combines animal models, microbiome analysis, cell-level profiling, and human sample validation to link gut C3 levels with resistance to enteric infections.

Who could benefit from this research

Good fit: Ideal candidates would include people who have recurrent or severe enteric infections (for example C. difficile) or parents of young children who experience frequent infectious diarrhea.

Not a fit: People with noninfectious gut conditions (such as functional bowel disorders or strictly metabolic problems) may not see direct benefit from this work.

Why it matters

Potential benefit: If successful, this could lead to new ways to prevent or treat infectious diarrhea by boosting or mimicking gut-produced C3.

How similar studies have performed: Previous animal and some human sample work supported local gut complement, but linking gut C3 levels to protection from infection using microbiome control and single-cell methods is relatively new.

Where this research is happening

BOSTON, UNITED STATES

Researchers

About this research

  1. This is an active NIH-funded research project — typically early-stage science, not a clinical trial accepting patient enrollment.
  2. Some NIH-funded labs run parallel clinical studies or seek volunteers for related work. To check, contact the principal investigator or institution listed above.
  3. For full project details, budget, and progress reports, visit the official NIH RePORTER page below.

View on NIH RePORTER →

Last reviewed 2026-05-15 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.