Bacterial crude extracts or ribosomes are recognized similarly by peripheral and mucosal B cells.

Bacterial ribosomes have been shown to induce effective humoral and cellular immunological responses to whole microorganisms. In this study, the numbers of specific antibody producing cells directed towards Klebsiella pneumoniae, Streptococcus pneumoniae, Streptococcus pyogenes and Haemophilus influenzae ribosomes or whole bacteria sonicates were compared in the peripheral blood and tonsils of 7 children, and in the tonsils, mesenteric and cervical lymph nodes of 10 sheep. No significant difference was noted between the two types of antigens, confirming that ribosomal preparations are able to mimic the immunogenicity of whole bacteria in the mucosae-associated lymphoid tissue.