Treg Cells As Potential Asthma Therapy?

Researchers are investigating the possibility the upregulation of regulatory T (Treg) cells as a new therapy to persistently alleviate asthma. A mouse study yields promising results.

Researchers are investigating the possibility the upregulation of regulatory T (Treg) cells as a new therapy to persistently alleviate asthma. A study recently published in the journal Nature, conducted by Kefei Wu of the Department of Hematology in Huadong Hospital at the Shanghai Medical College at Fudan University in China, and colleagues, describes how they combined IL-2 and glucocorticoid to expand antigen-nonspecific Treg cells and reduce airway inflammation.

Although previous research showed that an infusion of Treg cells stops airway inflammation in mice, there are many reasons the therapy hasn’t been pursued. A complex process, expensive equipment, side effects, and a weakening of the general immune system are among the limitations to the therapy, and the researchers add, “the optimal dose in systemic treatment of asthma is too high to be suitable for use in humans.”

However, the researchers say, “In this study we show that local application of glucocorticoid and IL-2 via the airway can effectively upregulate Treg cells and alleviate the pathological process of asthma in a mice model.” Further, they determined the optimal dose and form of dosage of glucocorticoid and IL-2.

Glucocorticoids of different types are currently used commonly to treat asthma, but the researchers say, “this treatment only relieves symptoms and does not reverse the progression or cure the disease.” They go on to say, “the therapeutic effect of glucocorticoids depends on sustained use, and even inhaled use can cause significant systemic activity and leads to multiple side effects.”

IL-2 makes asthma worse, but in this study, the researchers report, “the combined use of IL-2 and glucocorticoid intraperitoneally in a short term has proven to be useful in suppressing” asthma. They say, “In this study, we creatively used a PEG-modified IL-2 instead of a traditional recombinant human IL-2 to enhance the curative effect at a lower dose.”

Additionally, the authors report that “intratracheal rather than systemic administration not only helped further lower the therapeutic dose but also made it practical for clinical application.” They conclude, “We believe that such an effective therapy could greatly benefit patients with allergic airway disease in the future.”