B) Methods: Two protocols (i.e. preventive and therapeutic protocol) were designed to evaluate the effects of LTS61K in Der p sensitized and challenged mouse model of asthma.
C) Results: Both intranasal inoculations with LTS61K or LTS61K/Der p decreased allergen-induced airway inflammation and alleviated systemic TH2-type immune response. In addition, bronchoalveolar lavage (BAL) fluids and sera from LTS61K/Der p treated mice have higher concentrations of Der p-specific IgA than those of other groups. In the in vitro study, bone marrow-derived dendritic cells (BMDCs) and DC cell line, DC2.4 cells stimulated with LTS61K/Der p both secreted pro-inflammation cytokines IL-6 and TNF-a. In contrast, after LTS61K treatment, only BMDCs decreased production of IL-6 and TNF-a as well as decreased maturation. Furthermore, we found that pre-treatment BMDC with LTS61K inhibited Der p-induced NF-kB translocation which might explain the delayed maturation and decreased productions of IL-6 and TNF-a in LTS61K pre-treated BMDCs. Intratracheally adoptive transferred with LTS61K- or LTS61K/Der p-primed DC2.4 cells or BMDCS into Der p-sensitized mice decreased inflammatory cells infiltration and TH2-type chemokines in BAL fluids and alleviated airway inflammation.
D) Conclusions: our results show that LTS61K may influence DCs maturation and its cytokine production. On the other hands, LTS61K/Der p may induce more Der p-specific IgA production to decrease allergic TH2 cytokine responses and alleviate airway inflammation in murine model of asthma. These finding suggested that LTS61K may have clinical application as an immune-modulator effect on the diseases of allergy and asthma.