Almost five million people in Spain suffer from an autoimmune disease. If you wonder why you are one of them, the answer could lie in your genetics. But there is more, you need a trigger that could be in the consumption of tobacco or anti-inflammatory drugs.
The definition of autoimmune disease is simple: your body's defence system misinterprets the body's "signals" and attacks its own tissues. as if they were external agents. Sometimes autoimmunity targets antigens in a specific tissue and sometimes it affects multiple tissues because it targets a more ubiquitous set of antigens in the body; these are systemic autoimmune diseases.
However, the complexity of these pathologies is enormous, not only because of the range of autoimmune diseases we encounter, but also because of the very process that triggers the disease. Autoimmunity is not triggered by a single cause but by a series of cellular and molecular factors and events. In any case, even if an autoimmune process originates from a single trigger, other factors will always come into play and add to the complexity of the process.
Autoimmune processes are triggered by a a combination of genetic, environmental and physiological factors. A person's genetic characteristics are the main factor that determines an autoimmune disease. But other significant advances have been made in understanding the activation of this genetic factor; the trigger is linked to specific pathogens, chemical agents, toxins and hormones.
One of the biggest barriers to understanding autoimmune disease is the difficulty in defining the so-called "early events" in these pathologies.The first thing that happens in our organism and that is necessary to trigger the disease, before it appears, is that we recognise pathologies only when the symptoms appear. If we take into account that we only recognise pathologies when the symptoms appear, it is the professionals who must understand these symptoms and look for each of the factors that comprise this multi-causality.. In fact, autoimmune diseases are also described in four phases: the susceptibility to autoimmune disease, the onset of the disease, the spread of the disease and the regulatory phase.
The environmental factors such as smoking, ultraviolet rays or various infectious agents are responsible for activating the genetic factors to trigger the disease. More specifically, specific causal factors have been linked to pathologies such as silicon exposure as a key trigger for systemic lupus erythematosus. In other cases, the autoimmune response emerges following infection by a pathogen whose proteins have similar structures to proteins from the patient.
Susceptibility to autoimmune disease can be inherited, acquired, or both.
The direct influence of environmental factors
The mechanism linking an environmental factor to disease onset has not yet been generally defined, but its influence is clear.
For example, some chemical and pharmaceutical agents have been associated with specific symptoms of systemic autoimmune diseases. In particular, it is known that heavy metals such as mercuric chloride or polyvinyl chloride are triggers of autoimmune nephritis, or systemic sclerosis.
Smoking, the use of dryers - due to the chemical components of the materials from which they are made -, the inhalation of glue or exposure to silica dust and other toxins, can lead to episodes of rheumatoid arthritis, systemic lupus erythematosus, or scleroderma. Tobacco also aggravates and hinders the therapeutic action of the treatments prescribed to treat autoimmune pathology.
People working in industries related to carpentry, painting, perfumes or cosmetics are also more at risk of developing an autoimmune disease. As early as 1914, it was shown that stone masons who worked with stone developed scleroderma more than other people. More specifically, there are studies that relate the silica exposure with a broad spectrum of autoimmunity manifestations such as scleroderma, Sjorgen's syndrome or systemic lupus erythematosus.
Occasionally, some autoimmune diseases emerge as following pharmacological treatment. For example, medicines containing thiol and sulphonamide derivatives, as well as certain antibiotics or anti-inflammatory drugs, may cause pemphigus, a disease whose main symptom is the appearance of sores on the skin and mucous membranes.
On the other hand, viral or bacterial infections can trigger systemic autoimmune diseases in genetically predisposed individuals. The EpsteinBarr virus, HIV, human papillomavirus or influenza have been associated with systemic lupus erythematosus.. Similarly, Guillain Barre syndrome may be triggered by herpes or cytomegalovirus infection and idiopathic thrombocytopenic purpura disease may be preceded by chickenpox. As for bacterial infections, group A streptococcus may be behind rheumatic fever.
Bacteria and coeliac disease
Bacterial exposure is a major potential environmental risk factor for the development of coeliac disease, an autoimmune pathology of hereditary condition that affects 450,000 people in Spain.
Research conducted at Monash University in Australia has found that the ".isolated immune T-cell receptors of patients with coeliac disease can recognise protein fragments of certain bacteria that mimic the gluten fragments". This means that there may be a misrecognition of gluten, which is detected as bacterial proteins by T-cells.
While the response to proteins found in some bacteria is normal, a reaction to gluten proteins can develop because the immune system identifies both proteins. This finding could improve the diagnosis and treatment of coeliac disease.
