Intestinal microflora is to blame for autoimmune diseases

American immunologists have come to the conclusion that rheumatoid arthritis can be associated with the human intestinal microflora, namely the Prevotella copri bacterium. Such conclusions were made by the researchers after carrying out a series of experiments in mice and humans susceptible to this disease.

Rheumatoid arthritis is an inflammatory systemic autoimmune disease that affects the connective tissues of predominantly small joints and extremities. Usually the joints of the hands, knees, ankles, ankle are affected. What exactly causes a malfunction in the immune system, after which it begins to actively attack its own tissues, science has not found out to date.

Immunologist Dan Littman previously conducted studies in laboratory mice, which resulted in a relationship between the composition of the intestinal microflora and the increased activity of T-helpers (specific cells of the immune system) that protect the body from extracellular harmful microorganisms. With the activation of these cells in the body, harmful microorganisms are destroyed. Recently, a large number of evidences accumulated in the scientific community, that T-helpers are key cells in autoimmune diseases. In his studies, Dan Littman found that the production of T-helpers in the body depends on the composition of the intestinal microflora in mice. A little later, joint research in this field showed that they increase the activity of these cells and eventually trigger an autoimmune process in which rheumatoid arthritis develops in the mouse analogue, filamentous segmented bacteria that are part of the intestinal microflora.

All these data allowed scientists to suspect that the onset of rheumatoid arthritis in humans is also associated with the colonizing bacteria. A study was conducted of feces samples of 114 Americans, some of whom had been suffering from rheumatoid arthritis for a long time, and the rest had recently contracted this ailment. For the researchers, the most important group was the recently diagnosed group, since in this case people did not have time to receive treatment and the composition of their intestinal flora was unchanged.

As a result, scientists found that in a group with a newly diagnosed diagnosis, 75% of participants had a gram-negative pathogenic bacterium Prevotella copri (in a group where the duration of the disease was much longer, this bacterium was only 37%). The authors have several assumptions that can explain the relationship between a bacterium and rheumatoid arthritis, but they are confident that the onset of the disease involves several environmental factors, and how a combination of all factors triggers the disease process is yet to be clarified.

This fall, several scientific publications appeared that dealt with the relationship between autoimmune diseases and pathogenic foreign bacteria in the intestine. A team of researchers from New York reported that it established the cause of the development of multiple sclerosis, which is the soil bacterium Clostridium perfringens, and researchers from Finland assure that the enteroviruses they have detected trigger the development of type 1 diabetes.

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