[Pulmonary allergic responses were drived by atomization with ovalbumin in BALB/c mice with intestinal microflora...

The mice in which the intestinal microflora disruption resulted from antibiotic therapy are challenged by atomization with ovalbumin (OVA) to investigate the relation of allergic airway response and intestinal microflora disruption.

One hundred and twelve female BALB/c mice were divided at random into 6 groups. They were microbiota disruption I group, control I group, microbiota disruption II group, microbiota disruption and challenge group, challenge group and control II group. Cecal contents were collected for quantitative analysis of the intestinal microflora in mice in the former two groups and in mice in the latter four groups on day 6 and day 14, respectively. On day 14, the bronchoalveolar lavage fluid (BALF) was collected for cells counting. OVA-specific IgE in BALF and sera was detected by ELISA. Parts of lungs were collected for histopathology and detection of Th1 and Th2 cell levels by flow of cytometry.

The mice which were given antibiotics suffered from intestinal microbiota disruption. In microbiota disruption and challenge group, eosinophil and lymphocyte infiltration was significant and mucus secretion was increased in lung. The number of total cells, eosinophils, lymphocytes, neutrophils and OVA-specific IgE level were increased in BALF in microbiota disruption and challenge group. Th2 cell levels were increased and Th1 cell levels were not significantly different in microbiota disruption and challenge group compared with those in the control II group.

The allergic (Th2) immune response can be induced by atomization with ovalbumin in the mice in which the intestinal microflora disruption is resulted from antibiotic therapy. The result suggests that the intestinal microflora disruption is a risk factor for allergy and asthma.