Probiotic Cell Wall Component Boosts Chicken Defensin Without Triggering Inflammation

Peptidoglycan from probiotic L. rhamnosus enhanced avian defensin 9 expression and Salmonella killing in chicken cells without inflammatory cytokine production.

Huang, Juan et al.·Innate immunity·2020·Moderate EvidenceIn vitro / ex vivo
RPEP-04866In vitro / ex vivoModerate Evidence2020RETHINKTHC RESEARCH DATABASErethinkthc.com/research

Quick Facts

Study Type
In vitro / ex vivo
Evidence
Moderate Evidence
Sample
Chicken PBMCs, splenocytes, thymocytes, hepatocytes; embryo intestinal explants
Participants
Chicken PBMCs, splenocytes, thymocytes, hepatocytes; embryo intestinal explants

What This Study Found

Peptidoglycan from probiotic L. rhamnosus MLGA produced a dose-dependent increase in avian beta-defensin 9 (AvBD9) mRNA in multiple immune cell types (PBMCs, splenocytes, thymocytes, hepatocytes) and in chicken embryo intestinal explants (jejunum, ileum, cecum).

Functional validation: lysates from peptidoglycan-treated PBMCs and splenocytes showed increased ability to inhibit Salmonella Enteritidis growth, confirming the induced defensin was biologically active.

Critically, this defensin induction occurred without activating pro-inflammatory cytokines IL-1beta, IL-8, and IL-12p40. When peptidoglycan was digested with lysozyme, the hydrolysate actually suppressed these inflammatory cytokines.

In contrast, peptidoglycan from pathogenic S. aureus reduced AvBD9 expression in PBMCs and splenocytes, showing pathogen-derived vs probiotic-derived cell wall material has opposite effects on defensin production.

Key Numbers

AvBD9 up in all cell types; Salmonella killing enhanced; no IL-1β/IL-8/IL-12p40; S. aureus PG had opposite effect

How They Did This

In vitro and ex vivo study using chicken immune cells and embryonic intestinal explants. Peptidoglycan was purified from L. rhamnosus MLGA and S. aureus. AvBD9 expression measured by qPCR. Antimicrobial function tested by Salmonella growth inhibition assays. Cytokine expression (IL-1beta, IL-8, IL-12p40) monitored to assess inflammatory response.

Why This Research Matters

Antibiotics in poultry farming drive resistance. Probiotics can enhance natural defense, but the mechanism was unclear. This study shows a specific probiotic component (peptidoglycan) boosts antimicrobial peptide production without causing harmful inflammation. This precision is ideal: kill pathogens without damaging the gut.

The Bigger Picture

Antibiotics in poultry farming drive resistance. This study shows a specific probiotic component (peptidoglycan) boosts natural antimicrobial defenses without causing inflammation. This selective immune enhancement could replace prophylactic antibiotics in poultry production.

What This Study Doesn't Tell Us

Tested in chicken cells and embryonic explants, not in live chickens challenged with pathogens. The specific structural features of probiotic vs pathogenic peptidoglycan that explain their opposite effects were not identified. Only one probiotic species and one pathogen were compared. The dose-response relationship in live birds may differ from cell culture.

Questions This Raises

  • ?What structural differences between probiotic and pathogenic peptidoglycan explain their opposite effects?
  • ?Would this translate to disease protection in live chicken challenge studies?
  • ?Could purified peptidoglycan be added to feed as an alternative to whole probiotics?

Trust & Context

Key Stat:
Zero inflammation probiotic peptidoglycan enhanced antimicrobial peptide defense without any inflammatory cytokine production
Evidence Grade:
Moderate evidence from in vitro and ex vivo studies using multiple cell types and intestinal explants. Functional Salmonella killing confirmed.
Study Age:
Published in 2020. Probiotic-based antimicrobial peptide enhancement is an active research area in poultry science.
Original Title:
Peptidoglycan derived from Lactobacillus rhamnosus MLGA up-regulates the expression of chicken β-defensin 9 without triggering an inflammatory response.
Published In:
Innate immunity, 26(8), 733-745 (2020)
Database ID:
RPEP-04866

Evidence Hierarchy

Meta-Analysis / Systematic Review
Randomized Controlled Trial
Cohort / Case-Control
Cross-Sectional / ObservationalSnapshot without intervening
This study
Case Report / Animal Study
What do these levels mean? →

Frequently Asked Questions

Why does probiotic peptidoglycan behave differently from pathogenic peptidoglycan?

Probiotic and pathogenic bacteria have different cell wall structures. The probiotic version activates antimicrobial peptide production through NOD receptors without triggering the inflammatory alarm that pathogenic versions set off.

Could this reduce antibiotic use in chicken farming?

Potentially. If probiotic components boost chickens' natural antimicrobial defenses, they may resist infections without prophylactic antibiotics. This needs to be confirmed in actual farms.

Read More on RethinkPeptides

Cite This Study

RPEP-04866·https://rethinkpeptides.com/research/RPEP-04866

APA

Huang, Juan; Li, Junhui; Li, Qiufen; Li, Lin; Zhu, Nianhua; Xiong, Xiaowen; Li, Guanhong. (2020). Peptidoglycan derived from Lactobacillus rhamnosus MLGA up-regulates the expression of chicken β-defensin 9 without triggering an inflammatory response.. Innate immunity, 26(8), 733-745. https://doi.org/10.1177/1753425920949917

MLA

Huang, Juan, et al. "Peptidoglycan derived from Lactobacillus rhamnosus MLGA up-regulates the expression of chicken β-defensin 9 without triggering an inflammatory response.." Innate immunity, 2020. https://doi.org/10.1177/1753425920949917

RethinkPeptides

RethinkPeptides Research Database. "Peptidoglycan derived from Lactobacillus rhamnosus MLGA up-r..." RPEP-04866. Retrieved from https://rethinkpeptides.com/research/huang-2020-peptidoglycan-derived-from-lactobacillus

Access the Original Study

Study data sourced from PubMed, a service of the U.S. National Library of Medicine, National Institutes of Health.

This study breakdown was produced by the RethinkPeptides research team. We analyze and report published research findings without making health recommendations. All interpretations are based solely on the published abstract and study data.