TLR9 and allergic asthma: Previously, our group used allergen-free immunotherapy and showed that CpG plus proteins secreted by Mycobacterium tuberculosis [31] or CpG plus mycobacterial protein [33] were capable to negatively regulate allergic asthma, reduce eosinophilic and Th2 inflammation by a mechanism dependent on the deviation of immune response to Th1 cells and by a mechanism dependent on TLR9 and increase the influx of inflammatory monocytes.