Al­lergy-Re­duc­ing Bac­te­ria

Note­wor­thy

Al­ler­gies can be mer­ci­less. Even though sci­ence has ad­vanced in un­der­stand­ing the causes and we now have op­tions for treat­ment, al­ler­gies still take a toll on so many. Thank­fully, re­search con­tin­ues. 

Over the past decades, sev­eral ob­ser­va­tional stud­ies in­di­cated that chil­dren ex­posed to a farm en­vi­ron­ment are less likely to de­velop al­ler­gies and asthma than their ur­ban-lifestyle coun­ter­parts. The most prob­a­ble ex­pla­na­tion for this "farm ef­fect" is ex­po­sure to en­vi­ron­men­tal mi­crobes, many of which are largely ab­sent in more pris­tine ur­ban lo­ca­tions. This idea res­onates with the hy­giene hy­poth­e­sis, which ar­gues that un­der­ex­po­sure to cer­tain mi­crobes at an early age leads to ex­ag­ger­ated in­flam­ma­tory re­sponses and a greater propen­sity to al­ler­gic re­ac­tions later in life. 

The "farm ef­fect," al­ler­gies are re­duced in chil­dren that are ex­posed to farm an­i­mals early. Source

While early ex­po­sure to farm an­i­mals and their mi­cro­bio­mes, as well as to sur­round­ing dust and soil, ap­pears ben­e­fi­cial, it is much harder to iden­tify the mi­crobes re­spon­si­ble. A new study pub­lished in The New Eng­land Jour­nal of Med­i­cine – Ev­i­dence by an in­ter­na­tional team of sci­en­tists led by Dr. Ege at Helmholtz Mu­nich pin­points spe­cific bac­te­ria that may trig­ger pro­tec­tion. 

The re­searchers an­a­lyzed data from more than 1,000 chil­dren from rural ar­eas in Eu­rope. Us­ing nasal swabs and mat­tress dust sam­ples, as well as some ad­di­tional cow­shed dust sam­ples, they an­a­lyzed se­quence data and meta­bolic path­ways. They iden­ti­fied nine Gram-pos­i­tive en­vi­ron­men­tal bac­te­ria that ex­plain the in­verse as­so­ci­a­tion be­tween farm ex­po­sure and asthma. They also iden­ti­fied metabo­lites pro­duced by these mi­crobes that can bind to known re­cep­tors on hu­man air­way cells. 

Ze­ro­ing in on spe­cific en­vi­ron­men­tal mi­crobes, their metabo­lites, and how these in­ter­act with the hu­man host pro­vides new ma­te­r­ial for study­ing how spe­cific in­ter­ac­tions be­tween mi­crobes and the hu­man host pre­vent in­flam­ma­tory re­sponses. Hope­fully, this knowl­edge will trans­late into novel ap­proaches for pre­vent­ing the on­set of al­ler­gies and asthma. A big re­lief for so many in­di­vid­u­als world­wide.