The 1 st step essential for allergen-specific IgE antibody production upon the 2 nd step: Induction of non-specific IgE + small B cells containing secondly-sensitized allergen-specific ones in mice firstly-sensitized with an allergen

• Published in: Microbiology and immunology 2017-11
• Main Authors: Hannya, Natsuki, Ogita-Nakanishi, Hiromi, Kato, Ryuji, Ijiri, Yoshio, Hayashi, Tetsuya, Tanaka, Kazuhiko, Kawata, Ryo, Takenaka, Hiroshi, Kubota, Takahiro, Yoshida, Ryotaro
• Format: Article
• Language: English
• ISSN: 1348-0421
• DOI: 10.1111/1348-0421.12558

There was a significant amount of non-specific, but not of allergen (e.g., papain, mite feces, and 4 kinds of pollen)-specific, IgE antibodies (Abs) in the serum of normal mice. An intranasal (i.n.) injection of each allergen without adjuvant into mice caused an increase in total IgE Ab titers with a similar time course in the serum; but the stage in the initiation of allergy varied from allergen to allergen. Submandibular lymph node cells from normal mice contained papain-, but not mite feces- or pollen-specific IgE cells; and an i.n. injection of papain induced papain-specific IgE Abs in the serum. In contrast, 1 (i.n.) or 2 [i.n. and subcutaneous (s.c.)] injections of mite feces induced neither mite feces-specific IgE cells in the lymph nodes nor mite feces-specific IgE Abs in the serum. An i.n. sensitization with cedar pollen induced cedar pollen-specific IgE small B cells in the lymph nodes on day 10, when non-specific IgE Ab titers reached a peak in the serum, implying the induction of related allergen-specific IgE small cells as well. In fact, a 2 (s.c.) injection of ragweed (or cedar) pollen into mice sensitized i.n. once with cedar (or ragweed) pollen, but not with mite feces, induced a large amount of ragweed (or cedar) pollen-specific IgE Abs in the serum. These results revealed that when non-specific IgE small B cells in the lymph nodes from mice firstly-sensitized with an allergen contained secondly-sensitized allergen-specific ones, the mice produced IgE Abs specific for the secondly-injected allergen.