Toxoplasma gondii infection blocks the development of allergic airway inflammation in BALB/c mice

FENOY IGNACIO; GIOVANNONI MARCOS; BATALLA ESTELA; MARTIN VALENTINA; FRANK FERNANDA; PIAZZON ISABEL; GOLDMAN ALEJANDRA

CLINICAL AND EXPERIMENTAL IMMUNOLOGY

WILEY-BLACKWELL PUBLISHING, INC

Año: 2009 vol. 155 p. 275 - 284

0009-9104

There is a link between increased a llerg y and a reduct i on of some infect i onsin wester n count r ies. Epidemiolog ical data also show that respir ator y a llerg y is less frequent in people exp osed to orofaecal and fo o dbor ne microbes such as Toxoplasma gondii. Infect ion w ith T. gondii induces a st rong cell-mediated immunit y w ith a hig hly p olar ized T helper t y p e 1 ( Th1) resp onse in ear ly stages of infect ion. Using a well-know n mur ine mo del of allerg ic lung inflammat ion, we soug ht to invest igate w hether T. gondii infect ion could mo dulate the suscept i bilit y to de velop respir ator y a llerg ies. B oth acute and chronic infect ion w ith T. gondii before allerg ic sensit izat ion resulted in a diminished a llerg i c inflammat ion, as show n by a decrease in bronch oalveolar lavage ( BAL) eosinophilia, mononuclear and eosinophil ce ll infilt r a t i on around air ways and vessels and goblet ce ll hy per plasia. Low allergen-specific immunog lobulin (Ig)E and IgG1 and hig h le vels of allergen-specific IgG2a ser u m ant ibo dies were detecte d. A decreased inter leukin (IL)-4 and IL-5 pro duct ion by ly mph no de cells was obser ved, w hile no ant igen-specific inter feron- g increase was dete cted. Hig her le vels of the re gulator y cy tokine IL-10 were found in BA L f rom infecte d mice. These re sults show that both acute and ch ronic par asite infect i on substant ially blocke d de velopment of air way inflammat ion i n a dult BALB/c mice. Our re sults supp or t the hy p othesis that T. gondii infect ion cont r ibutes to protect ion against allerg y in humans.