Aspergillus Fumigatus Infection Induces B1 Lymphocytes To Produce Antibodies In The Absence Of µ-Chain Expression

S. Ghosh , S. Hoselton , J. Schuh

Author address: 

North Dakota State University, Fargo, ND

Abstract: 

Surface, membrane-bound immunoglobulin M (IgM) expression early in B cell development is considered essential for the differentiation of B lymphocytes to antibody- producing cells, as only in IgM+ B cells is the heavy chain locus rearranged to express antibodies of other classes. MuMT mice on the C57BL/6 background contain a deletion of the first µ exon, which codes for the transmembrane domain of the immunoglobulin µ chain gene. These mice have been described as deficient of both mature B cells and plasma cells. In assessing the pulmonary pathology associated with A. fumigatus infection in the MuMT mice, we have observed that these animals produce antibodies in the absence of peripheral B2 lymphocytes (CD19+/CD23+). We hypothesized that these antibodies were produced in response to the stimulation of B1 cells in the pulmonary tissue. We report that MuMT mice have CD19+/CD9+/IgD+ cells in the lungs which may be responsible for the robust IgE and IgG2a production that is noted upon exposure to A. fumigatus. Our findings reveal a complete lack of B2 (CD19+/CD23+) cells in MuMT mice. These finding reveal the existence of an IgD B1 lymphocyte pathway for the production of antibodies in MuMT animals in the absence of conventional B2 lymphocytes.
2011

abstract No: 

A35

Full conference title: 

American Thoracic Society
    • ATS 2011