IL-10-treated dendritic cells decrease airway hyperresponsiveness and airway inflammation in mice.

Area of Science:

• Immunology
• Allergy Research
• Cellular Immunology

Background:

• Interleukin-10 (IL-10) is known to influence dendritic cell (DC) function.
• However, its specific impact on airway hyperresponsiveness (AHR) and inflammation remains unclear.

Purpose of the Study:

• To investigate the role of IL-10 in regulating DC function.
• To determine the importance of IL-10 in controlling allergen-induced AHR and airway inflammation.

Main Methods:

• Dendritic cells were generated in vitro with or without IL-10.
• In vivo, IL-10-treated DCs from IL-10(+/+) and IL-10(-/-) mice, pulsed with ovalbumin (OVA), were transferred to recipient mice.
• Airway hyperresponsiveness, cytokine levels, bronchoalveolar lavage (BAL) fluid composition, and lung histology were assessed.

Main Results:

• In vitro, IL-10 treatment reduced DC expression of CD11c, CD80, CD86, and IL-12, suppressing T helper 2 (Th2) cytokine production.
• In vivo transfer of IL-10-treated DCs prevented AHR, airway eosinophilia, and Th2 cytokine increases in naive mice upon challenge.
• IL-10-treated DCs also suppressed these responses in sensitized and challenged mice, with increased IL-10 and CD4(+)IL-10(+) T cells observed in BAL fluid.

Conclusions:

• IL-10-treated DCs are effective suppressors of AHR, inflammation, and Th2 cytokine production.
• These regulatory effects are partly mediated by the induction of endogenous IL-10 production.
• Modulating DC function with IL-10 can attenuate lung allergic responses, including AHR development.