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Operating and Biocontainment Procedures of a Facility for Laboratory Mice with a Natural Microbiome: Immunophenotyping Procedure

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The old friends hypothesis: evolution, immunoregulation and essential microbial inputs.

Graham A W Rook¹

¹Centre for Clinical Microbiology, Department of Infection, UCL (University College London), London, United Kingdom.

Frontiers in Allergy

|September 29, 2023

Summary

This summary is machine-generated.

Modern lifestyles reduce exposure to essential microorganisms, leading to immune system dysregulation and increased chronic inflammatory diseases. Restoring this exposure is key to improving immune health and preventing allergies and autoimmunity.

Keywords:

biodiversity epithelial barrier evolution immunoregulation inflammation microbiota natural environment socioeconomic status

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Area of Science:

Immunology
Microbiology
Public Health

Background:

Rising prevalence of chronic inflammatory disorders (allergies, autoimmunity, inflammatory bowel diseases) in urbanized societies.
Increased inflammatory biomarkers correlate with higher risks of metabolic, cardiovascular, and psychiatric conditions.
These trends suggest a failure in immune system regulation, preventing attacks on harmless substances and resolving inflammation.

Purpose of the Study:

To investigate the Old Friends Hypothesis regarding immune dysregulation.
To identify microorganisms crucial for immune system development and regulatory T cell (Treg) expansion.
To understand the evolutionary basis of human dependence on specific microorganisms for immunomodulation.

Main Methods:

Utilizing an evolutionary approach to identify co-evolved microorganisms essential for immune regulation.
Analyzing the role of symbiotic microbiota components in immune system development.
Identifying lifestyle changes impacting exposure to these 'Old Friends' microorganisms.

Main Results:

The 'Old Friends' hypothesis posits that inadequate exposure to specific microorganisms impairs immune regulation.
Essential immunomodulatory organisms are acquired from mothers, family, and the natural environment, forming part of a healthy microbiota.
Lifestyle changes, often linked to lower socioeconomic status in developed nations, disrupt this crucial exposure.

Conclusions:

Restoring exposure to 'Old Friends' microorganisms can correct immune regulatory deficits.
Interventions in education, diet, and urban planning can help re-establish beneficial microbial exposures.
Addressing epithelial damage and other contributing factors alongside microbial restoration is essential for comprehensive immune health.