DEVELOPMENT OF ANTIBODY-FORMATION IN GERMFREE AND CONVENTIONALLY REARED RABBITS - THE ROLE OF INTESTINAL LYMPHOID-TISSUE IN ANTIBODY-FORMATION TO ESCHERICHIA-COLI ANTIGENS

  • 1 January 1980
    • journal article
    • research article
    • Vol. 26  (2) , 81-93
Abstract
The occurrence of cells which produce natural bactericidal and hemolytic antibodies (the so-called background plaques) was studied by the plaque method in lymphatic tissues of germ-free and conventionally reared rabbits of various ages. In conventional rabbits the cells which produce natural bactericidal antibodies against E. coli 086 appear early after birth in organized intestinal lymphatic tissue. Their number increases during development, and they appear in mesenteric lymph nodes and spleen; their number decreases due to aging. Natural hemolytic antibodies are produced throughout life predominantly in the spleen of conventional rabbits. In germ-free rabbits the appearance of natural bactericidal or hemolytic antibodies was not demonstrated during the tested period of 16 wk of life. When comparing the immunological capacity after parenteral immunization or after stimulation of cells from various organs cultivated in diffusion chambers, the response to germ-free rabbits was very low or lacking. The differences between the reactivity of germ-free and conventional rabbits were especially marked when studying the specific and non-specific (polyclonal) response after administration of E. coli suspension. The nature and possible causes underlying the differences in immunological activity in various species of germ-free animals are discussed.