Increase of eosinophilic cell population in bone marrow of rats by immunization with Ascaris suum antigen

Immunization of rats with the antigen, Ascaris suum extract, increased the number of peripheral eosinophils. Analysis by Western blot and reverse transcription-polymerase chain reaction revealed that the levels of major basic protein and its mRNA in the bone marrow were also increased, suggesting that eosinophilic cell population in the bone marrow is increased by the immunization. These findings indicate that immunization with this antigen stimulates differentiation of progenitor cells to eosinophils in the bone marrow, and induces blood eosinophilia.