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Intestinal barriers to bacteria and their toxins
1Infectious Diseases Department, Naval Medical Research Institute, Bethesda, Maryland 20814-5055.
Annual Review of Medicine
|January 1, 1990
Summary
The intestinal barrier uses immunologic and nonimmunologic defenses to prevent pathogen spread. Enhancing these mucosal barriers is now feasible with new technologies.
Area of Science:
- Gastroenterology and Immunology
- Microbiology
- Biotechnology
Background:
- The intestinal barrier, comprising mechanical, immunological, and microbial factors, protects against enteric pathogens.
- Pathogen translocation across the mucosal barrier is a risk, particularly in immunocompromised individuals.
- Existing defenses include epithelial integrity, mucus, antibodies, microbial metabolites, and peristalsis.
Purpose of the Study:
- To explore the mechanisms of intestinal barrier function.
- To identify strategies for enhancing mucosal barrier defenses.
- To assess the feasibility of improving intestinal barrier integrity.
Main Methods:
- Review of immunologic and nonimmunologic protective mechanisms.
- Analysis of factors limiting pathogen proliferation and dissemination.
- Evaluation of emerging biotechnological approaches for barrier enhancement.
Main Results:
- The intestinal barrier relies on a complex interplay of physical, chemical, and immunological components.
- Peyer's patches and lymphoid structures can facilitate pathogen translocation, especially in immunosuppression.
- Advances in genetic engineering, drug delivery, and immunomodulation offer new avenues for intervention.
Conclusions:
- Understanding intestinal barrier limitations is crucial for developing therapeutic strategies.
- Genetic engineering of bacteria, oral delivery systems, and immunomodulators show promise for enhancing mucosal immunity.
- Enhancement of intestinal mucosal barriers is a feasible goal for preventing and treating enteric infections.
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