Despite having similar lifestyle and genetics ancestries, the environment of Amish farmers mold their innate immunity resilient enough to battle asthma and allergic sensitization as compared to Hutterite’s environment. The Amish practice traditional farming which translate into minimum exposure to synthetic chemicals.
A research funded by the US National Institute of Health (NIH) has recently found the levels of asthma and allergic sensitization are four to six times lower in Amish children than in the Hutterite, even though both populations have similar lifestyles, making environment and exposure to chemicals a major contributor to asthma development.
Based on the sharing of genetic ancestry and lifestyle, the two major farming populations in the US – the Amish and Hutterite — were considered in the research because of their different farming practices, traditional farming and industrial farming respectively. In this research, where 60 children were the part of study design, the environmental exposures, genetic ancestry and immune profiles of both the Amish and the Hutterite children were assessed. Significant difference between the asthma rate of both the populations was found but due to little knowledge on their immune systems, not much could be concluded.
The researchers carried out various steps like measuring the levels of allergens and endotoxins from the indoor dust samples, microbial composition assessment and measuring the blood serum IgE levels, cytokine responses, gene expression and peripheral blood leukocytes.
On scrutinizing the blood samples against allergic asthma markers, phenotypes and functions of innate immune cells showed distinction of varied degree. The microbial compositions of the dust samples and the levels of endotoxins in Amish family homes were 6.8 times higher than the Hutterite.
For further digging, researchers applied the respective dust samples found in both homes of the Amish and the Hutterite, to a mouse model with an intent to observe experimental allergic asthma response. When the mice inhaled the dust extracts from the Amish homes their airways got inhibited by hyper-reactivity and eosinophilia, while the effects were not as strong when dust from the homes of Hutterite was used. Another set of mice which were deprived of having innate immune signaling system — ‘MyD88 and Trif’ molecules — in their body, did not show symptoms of allergy upon inhaling the dust particles.
The above found dust samples and results from mice model helped them believe that basically the Amish children had greater number of neutrophils in their blood, which protects against asthma causing allergens. They also had lower levels of eosinophils and similar levels of monocytes which lead to inflammation of the airways, even though the dust extracted from the homes of the Amish children was more asthma prone as seen in the mice. Despite having the same monocytes levels, monocytes from Amish children showed a suppressive phenotype. This goes to show the exposure to microbial allergen in early life and lowered exposure to chemical toxins may be the key to preventing increased risk of asthma development.
Is A Toxic Free Environment The Answer To Asthma Immunity?
According to CDC, a high number of American population, 8% of them, is afflicted with asthma and 57% out of them are children. Asthma is a serious, chronic disease which causes shortness of breath, wheezing, coughing and tightness in the chest area. The asthmatic develop irritation and swelling in the airways which disturb the process of respiration. Asthma ranges from simple difficulty in breathing to severe respiratory allergic reactions.
Urban environments have usually severely developed asthmatics, because of their exposure to toxic environments in their childhoods, due to imbalanced T-helper cells and passive exposure to smoke. According to the Journal of Allergy and Clinical Immunology, asthma is basically an inflammatory response caused by the T-helper type (Th)-2 lymphocytes when airborne allergens enter the blood stream. The exposure to microbes in early life has been called as an effective way of increasing the immunological response to allergens. The innate immunity plays a vital role since it is the first line of defense the environmental irritants encounter when they enter the body and these interactions play a role in establishing the phenotype of the disease.