Therapeutic Potential of Selected Probiotic Strains in a Murine Model of Ovalbumin-Induced Atopic Dermatitis and Asthma.

Atopic dermatitis (AD) and asthma are key manifestations of the atopic march, characterized by a progressive development of allergic diseases from early skin inflammation to later respiratory involvement. Emerging evidence highlights the role of gut microbiota in modulating immune responses. However, the therapeutic potential of specific probiotic strains in preventing or mitigating the atopic march remains underexplored. This study aimed to evaluate the immunomodulatory and therapeutic effects of selected probiotic strains in a murine model of ovalbumin (OVA)-induced AD and asthma. Mice received oral administration of B. plebeiu, B. ovatus, F. duncaniae, F. taiwanense, and F. prausnitzii for four weeks before being exposed to OVA to induce AD and, later, asthma. Skin reactions were assessed after OVA application, and asthma was induced via aerosolized OVA. Afterward, blood and lung fluid samples were collected to evaluate immune markers such as total IgE, OVA-specific IgE, and IL-4. The results showed that B. plebeius improved skin histology in AD, while B. ovatus initially induced AD symptoms but later reduced them significantly between days 40 and 54. B. plebeius and B. ovatus reduced serum total IgE in asthma. B. plebeiu, B. ovatus, F. duncaniae, F. taiwanense, and F. prausnitzii significantly lowered OVA-IgE levels in serum and IL-4 levels in lung fluid (p < 0.05). These selected probiotic strains helped reduce allergic skin responses and, later, asthma by decreasing inflammation, particularly IL-4. These findings support the potential of these probiotics to prevent or mitigate the progression from AD to asthma and offer promising insight into targeted probiotic interventions for allergic diseases.