Related Experiment Videos
Intestinal bacteria and rheumatic disease
1Department of Medical Microbial Ecology, Karolinska Institutet, Stockholm, Sweden.
Abstract:
The striking clinical and pathological similarities between certain naturally occurring infectious diseases in animal species and those of some human rheumatic diseases, such as rheumatoid arthritis (RA), have stimulated the search for a microbial etiology of the latter syndrome. A long series of microbial species, including aerobic and anaerobic intestinal bacteria, mycoplasma and several viruses have been put into focus. Most often, however, an initially positive report has been followed by several reports denying an etiological role of the microbial species in focus. However, the concept of a microbial trigger in the etiology and symptomatology of RA is still a subject of intense debate. Recent results have indicated a reversed effect of gram-positive vs. gram-negative intestinal bacteria on adjuvant-induced arthritis in germfree rats and microbial peptidoglycans have been shown to play a major role in this experimental model. It has been shown that the intestinal flora may include bacteria containing antigenic determinant(s) cross-reacting with some markers within the HLA-system. The intestinal flora may also influence upon several digestive and absorptive functions and thereby acting upon parameters of importance in the development of rheumatic disease.
Insights
The gut microbiome
Area of Science:
- Microbiology
- Immunology
- Rheumatology
Background:
- Similarities exist between animal infectious diseases and human rheumatoid arthritis (RA).
- The microbial etiology of RA remains debated, with various bacteria and viruses investigated.
- Previous studies often yielded conflicting results regarding microbial involvement.
Purpose of the Study:
- To explore the potential role of the gut microbiome in the etiology and symptomatology of rheumatoid arthritis (RA).
- To investigate the influence of intestinal bacteria and their components on experimental arthritis models.
Main Methods:
- Examined the effects of gram-positive versus gram-negative intestinal bacteria on adjuvant-induced arthritis in germfree rats.
- Investigated the role of microbial peptidoglycans in experimental arthritis.
- Assessed cross-reactivity between intestinal bacteria antigens and HLA-system markers.
- Studied the impact of intestinal flora on digestive and absorptive functions.
Main Results:
- Gram-positive and gram-negative intestinal bacteria exhibited opposing effects on adjuvant-induced arthritis.
- Microbial peptidoglycans were identified as significant factors in this arthritis model.
- Certain intestinal bacteria possess antigens that cross-react with HLA-system markers.
- The intestinal flora influences digestive functions relevant to rheumatic disease development.
Conclusions:
- The gut microbiome, including specific bacteria and peptidoglycans, plays a significant role in the development of rheumatic diseases like RA.
- Intestinal bacteria may trigger or modulate RA through immune cross-reactivity and effects on gut function.
- Further research into the gut microbiome's role in RA is warranted.