Clinical and Diagnostic Laboratory Immunology, 03 1994, 150-154, Vol 1, No. 2
Copyright © 1994 by the American Society for Microbiology. All rights reserved.

Immune response in the lungs following oral immunization with bacterial lysates of respiratory pathogens

C Ruedl, M Fruhwirth, G Wick and H Wolf
Institute for General and Experimental Pathology, Medical School, University of Innsbruck, Austria.

We have investigated the local immune response of the BALB/c mouse respiratory tract after oral immunization with a bacterial lysate of seven common respiratory pathogens. After two immunization on five consecutive days, we examined the immunoglobulin (immunoglobulin G [IgG], IgM, and IgA) secretion rates of cells isolated from the lungs and compared them with those of spleen cells of orally immunized and nonimmunized animals by using a new test system based on time-resolved fluorescence. The procedure followed the principle of the classical ELISPOT test with nitrocellulose-bottomed microtiter plates, but europium (Eu3+)-linked streptavidin rather than enzyme-conjugated streptavidin was used, with the advantage of quantifying secreted immunoglobulins instead of detecting single antibody-secreting cells. Lymphocytes isolated from the lungs of treated animals revealed significant increases in total and antigen-specific IgA synthesis compared with the rates of the controls, whereas IgG and IgM production rates showed no remarkable differences. In addition, the sera of treated mice revealed higher antigen-specific IgA titers but not increased IgM and IgG levels. We conclude that priming the gut- associated lymphoid tissue with bacterial antigens of pneumotropic microorganisms can elicit an enhanced IgA response in a distant mucosal effector site, such as the respiratory tract, according to the concept of a common mucosa-associated immune system.

This article has been cited by other articles:

• Baker, D. G. (1998). Natural Pathogens of Laboratory Mice, Rats, and Rabbits and Their Effects on Research. Clin. Microbiol. Rev. 11: 231-266 [Abstract] [Full Text]