Send to

Choose Destination
Am J Respir Crit Care Med. 2009 Feb 1;179(3):186-93. doi: 10.1164/rccm.200806-951OC. Epub 2008 Nov 21.

Lactobacillus reuteri-induced regulatory T cells protect against an allergic airway response in mice.

Author information

The Brain-Body Institute, St. Joseph's Healthcare, 50 Charlton Avenue East, T3312, Hamilton, ON L8N 4A6, Canada.



We have previously demonstrated that oral treatment with live Lactobacillus reuteri can attenuate major characteristics of the asthmatic response in a mouse model of allergic airway inflammation. However, the mechanisms underlying these effects remain to be determined.


We tested the hypothesis that regulatory T cells play a major role in mediating L. reuteri-induced attenuation of the allergic airway response.


BALB/c mice were treated daily with L. reuteri by gavage. Flourescent-activated cell sorter analysis was used to determine CD4(+)CD25(+)Foxp3(+)T cell populations in spleens following treatment with L. reuteri or vehicle control. Cell proliferation assays were performed on immunomagnetic bead separated CD4(+)CD25(+) and CD4(+)CD25(-) T cells. CD4(+)CD25(+) T cells isolated from, ovalbumin naive, L. reuteri treated mice were transferred into ovalbumin-sensitized mice. Following antigen challenge the airway responsiveness, inflammatory cell influx and cytokine levels in bronchoalveolar lavage fluid of recipient mice were assessed.


Following 9 days of oral L. reuteri treatment, the percentage and total number of CD4(+)CD25(+)Foxp3(+)T cells in spleens significantly increased. CD4(+)CD25(+) cells isolated from L. reuteri-fed animals also had greater capacity to suppress T-effector cell proliferation. Adoptive transfer of CD4(+)CD25(+) T cells from L. reuteri-treated mice to ovalbumin-sensitized animals attenuated airway hyper-responsiveness and inflammation in response to subsequent antigen challenge.


These results strongly support a role for nonantigen-specific CD4(+)CD25(+)Foxp3(+) regulatory T cells in attenuating the allergic airway response following oral treatment with L. reuteri. This potent immuno-regulatory action may have therapeutic potential in controlling the Th2 bias observed in atopic individuals.

[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for Atypon
Loading ...
Support Center