Effect of the Bryostatin 1 in B cells under TGF-B-stimulated condition.

IgA protects the body from invaders in the mucosal sites, but its role in allergic diseases, such as hay fever, is poorly understood. We demonstrate an increased susceptibility to cedar pollen-induced hay fever associated with increasing pollen penetration into the body in IgA-deficient mice, indicating that IgA prevents pollen invasion on the mucosa. We identified Bryostatin 1, an anti-carcinogenic Protein kinase C (PKC) delta activator, as an IgA/IgE class-switching regulator in B cells. Bryostatin 1 enhanced IgA production through induction of germline transcript (GLT) alpha. We performed RNA-seq analysis to reveal the molecular mechanisms of Bryostatin 1-mediated IgA class-switching.