Experimental pulmonary cavity formation by mycobacterial components and synthetic adjuvants.
An investigation was undertaken to determine the components of mycobacteria responsible for pulmonary cavity formation in tuberculosis. Rabbits received an intrapulmonary injection through the chest wall, of mycobacterial protein, II-p, mixed with either mycobacterial lipids, synthetic adjuvants or Nocardia cell wall skeleton as adjuvant. Six weeks later, they were killed and the lung lesions were examined. Cavities and necrosis were produced by the injection of II-p mixed with cord factor, Nocardia cell wall skeleton or N-acetylmuramyl dipeptide conjugated with long-chain branched fatty acids. Cavities were not produced by either the injection of II-p together with phospholipid, N-acetylmuramyl dipeptide (MDP), MDP-derivatives having no long-chain branched fatty acid, or by the injection of individual components of the mixtures. The results suggest that in tuberculosis a mycobacterial component with a long-chain branched fatty acid such as mycolic acid plays an important role in pulmonary cavity formation by enhancing the antigenicity of mycobacterial protein and helping it induce cell-mediated immunity at the site of the lesion. Passive transfer with sera from rabbits highly sensitized with tubercle bacilli failed to enhance cavity formation in the recipient animals.
D000276:Adjuvants, Immunologic / Q000494:pharmacology*; D000818:Animals; D001426:Bacterial Proteins / Q000494:pharmacology*; D002473:Cell Wall; D007106:Immune Sera; D008168:Lung / Q000187:drug effects / Q000473:pathology*; D008297:Male; D009161:Mycobacterium / Q000032:analysis*; D009168:Mycobacterium phlei / Q000032:analysis* / Q000276:immunology; D009615:Nocardia; D011817:Rabbits; D014397:Tuberculosis, Pulmonary / Q000473:pathology*
D000276:Adjuvants, Immunologic; D001426:Bacterial Proteins; D007106:Immune Sera