Related Experiment Video
Updated: Aug 6, 2026
07:34
Induction of Intestinal Inflammation by Adoptive Transfer of CBir1 TCR Transgenic CD4+ T Cells to Immunodeficient Mice
Published on: December 16, 2021
Lacticaseibacillus Strains Shape Intestinal Immune Homeostasis by Promoting Antimicrobial Activity and Modulating
María José Martínez Monteros1, Carolina Maldonado Galdeano1,2, Gabriela Perdigón1,2
1Laboratorio de Inmunología, Centro de Referencia para Lactobacilos (CERELA-CONICET). Tucumán, Chacabuco 145 - (T4000ILC), San Miguel de Tucumán, Argentina.
Probiotics and Antimicrobial Proteins
|July 25, 2026
Summary
Two probiotic strains, Lacticaseibacillus casei CRL 431 and Lacticaseibacillus paracasei CNCM I-1518, enhance intestinal defense by boosting antimicrobial peptides and modulating immune responses. This supports their use in functional foods for improved gut health.
Area of Science:
- Microbiology
- Immunology
- Gastroenterology
Background:
- Probiotics bolster intestinal defenses via immune modulation, barrier enhancement, and antimicrobial protein induction.
- Understanding strain-specific mechanisms is key for probiotic applications in medicine and functional foods.
Purpose of the Study:
- To investigate if Lacticaseibacillus casei CRL 431 and Lacticaseibacillus paracasei CNCM I-1518 promote endogenous antimicrobial peptide production and shape mucosal immune responses.
- To evaluate the impact of these probiotics on epithelial barrier integrity, immune cell function, and antimicrobial activity in a murine model.
Main Methods:
- Oral administration of specific probiotic strains to mice.
- Assessment of epithelial barrier function, Goblet and Paneth cell responses, and cytokine profiles.
- In vitro analysis of soluble intestinal factors' effects on immune cell chemotaxis, antigen-presenting cell maturation, and macrophage survival.
Main Results:
- Probiotic strains increased Goblet cell numbers and tight junction proteins, enhancing barrier integrity without affecting permeability.
- Intestinal fluids showed antimicrobial activity linked to Paneth cell activation and enteric α-defensin 5 production.
- Probiotic supplementation induced a balanced immune response with both pro-inflammatory and anti-inflammatory cytokines, promoting immune cell chemotaxis and macrophage survival.
Conclusions:
- These probiotic strains integrate antimicrobial peptide induction with immune modulation to strengthen intestinal defenses.
- The study provides mechanistic insights into how probiotic consumption enhances endogenous antimicrobial activity and immune modulation for pathogen resistance.
Related Concept Videos
01:21Microbiota Modulation by Antibiotics
Antibiotics have revolutionized modern medicine by saving countless lives from bacterial infections. However, their widespread use has inadvertently harmed the delicate balance of the human gut microbiota. The gut microbiota, a complex community of bacteria, archaea, viruses, and fungi, plays a vital role in regulating metabolism, immune responses, and maintaining intestinal health. Antibiotics, especially broad-spectrum types, disrupt this ecosystem by eradicating both harmful and beneficial...
01:18Functions of the Gut Microbiota
The gut microbiota includes trillions of microorganisms that colonize the human gastrointestinal tract, including bacteria, archaea, viruses, and fungi. This complex ecosystem plays a critical role in maintaining intestinal and systemic health. Most of these microbes inhabit the large intestine, establishing a relatively stable and diverse community that contributes to gut homeostasis through various metabolic, immunological, and protective mechanisms.Dominant bacterial phyla, such as...
01:18Dysbiosis of the Gut Microbiota
The human gut microbiome includes a diverse array of microbial species, including beneficial commensals and opportunistic pathogens, which interact to support host health. These microbes contribute to essential functions such as nutrient metabolism, immune system modulation, and maintenance of intestinal barrier integrity. However, disruptions to this equilibrium—referred to as dysbiosis—can have widespread physiological consequences.Dysbiosis is often characterized by reduced microbial...
01:27Microbiota of the Large Intestine
The large intestine hosts the most densely populated microbial ecosystem in the human body. This complex community primarily consists of anaerobic bacteria, with Bacillota (formerly Firmicutes) and Bacteroidota (formerly Bacteroidetes) as the predominant groups. The distribution of these microbes varies along different sections of the large intestine, influenced by local environmental factors such as oxygen availability and nutrient composition.The cecum, located at the beginning of the large...
01:27Microbiota of the Stomach and Small Intestine
The human gastrointestinal (GI) tract is characterized by distinct physicochemical conditions that shape its microbial communities. Among these, the stomach presents a particularly challenging environment for microbial colonization due to its highly acidic pH, ranging from 1 to 3. This extreme acidity effectively limits microbial density. However, certain acid-tolerant microorganisms are capable of surviving in this niche. Notably, Helicobacter pylori can colonize the gastric mucosa,...
01:22Probiotics
Probiotics are live, non-pathogenic microorganisms that confer health benefits by modulating the gut microbiota. The human gastrointestinal tract harbors a complex microbial ecosystem, and the balance of this microbiota is crucial for digestive and systemic health. Among the most extensively studied and utilized probiotics are species formerly classified within the genera Lactobacillus and Bifidobacterium. These organisms not only naturally colonize the human gut but are also consumed through...