Infections and autoimmunity: a panorama.

Area of Science:

• Immunology
• Microbiology
• Infectious Diseases

Background:

• Historical disease causation theories evolved from supernatural beliefs to the germ theory.
• The rise of chronic and autoimmune diseases necessitates re-evaluating the role of microorganisms.
• Current models lack clear explanations for the link between infections and autoimmune conditions.

Purpose of the Study:

• To review the literature on associations between infections and 16 autoimmune diseases.
• To critically analyze clinical, serological, and molecular evidence.
• To explore experimental models of infection-induced autoimmunity and protection.

Main Methods:

• Literature review of clinical, serological, and molecular studies.
• Analysis of experimental models for autoimmune disease induction and prevention by infection.
• Examination of the role of microbiota and endogenous retroviruses.

Main Results:

• Chronic infections (e.g., Epstein-Barr virus, cytomegalovirus, H. pylori) are implicated in autoimmune disease development in susceptible individuals.
• A pattern suggests infections can influence autoimmune disease progression.
• The healthy carriage state of infections is common and warrants further investigation.

Conclusions:

• Understanding the mechanisms of healthy infection carriage is crucial for differentiating between health and chronic illness.
• Early colonization with 'old friends' microbes (e.g., lactobacilli, bifidobacteria) may be vital for immune health and protection.
• Further research should focus on the transition from healthy carriage to infectious or autoimmune syndromes.