D1.191 - Respiratory bacterial lysate (OM-85)-loaded dissolving microneedle array patch modulates HDM-induced allergic airway inflammation and airway hyperresponsiveness in a murine asthma model

Respiratory bacterial lysate (OM-85, lyophilized lysate from 8 respiratory pathogenic bacteria) is an oral immunomodulator used to support infection-prone or immune-vulnerable populations. This study evaluates whether transdermal delivery via a dissolving microneedle array patch (dMAP) can modulate HDM-induced allergic airway inflammation in asthma.

Intranasal HDM extract-sensitized female BALB/c mice were used to establish allergic asthma (BV: OM-85-based respiratory bacterial lysate). Mice were assigned to four groups (n=5/group): Sham, HDM control, BVL (2 µg BV-loaded dMAP), and BVH (10 µg BV-loaded dMAP).

Transdermal delivery of BV-dMAP attenuated airway hyperresponsiveness compared with the HDM control. ELISA of lung lysates demonstrated statistically significant downregulation of IL-4, IL-13, IL-33, and TNF-α in both BVL and BVH groups relative to HDM. Significant increase in IL-10, and IFN-γ observed specifically in the BVH group, indicating dose-dependent immune modulation. BALF analysis supported reduced inflammatory cell influx, including decreased eosinophil-dominant inflammation. Serum HDM-specific IgE levels were lower in both BV-dMAP groups, consistent with lung cytokine outcomes. Histological examination indicated reduced airway inflammation and goblet cell hyperplasia, with comparatively more pronounced effects in BVH than BVL.

Transdermal delivery of BV-dMAP modulates allergic airway inflammation and attenuates airway hyperresponsiveness in a murine asthma model dose dependently. No adverse reactions related to BV-dMAP were observed. The results indicate potential immune-modulatory roles of BV-dMAP as a transdermal therapeutic strategy for allergic asthma.