Immunological Studies in Tuberculosis

[摘要] The prevalence of avian tuberculosis has been pointed out in the preceding pages. What rôle this type of disease and avian tubercle bacilli play in the epidemiology of human infection and disease is not yet clear.Human tuberculosis, as we see it today, is unquestionably due in most cases to human tubercle bacilli. The occasional isolation of types of bacilli from sputum or lesions of tuberculous patients which do not fit into the standard pattern of human, bovine and avian strains, suggest the possibility of a mutation. At present we have no definite proof that the avian organism may change into the human or bovine type. The only evidence we have is that it has apparently been isolated from human beings by Lowenstein, Urbach, Joannovich, Deutsch and others and that of L'Esperance finding it in Hodgkin's disease. Although the avian tubercle bacillus is found very rarely in human beings, we must take into consideration that this organism is a possible epidemiological factor when we map out our campaign against tuberculosis in man. The infection may enter the body either through eggs (raw or partially cooked) which contain the bacilli or through partially cooked chickens.The eradication of avian tuberculosis must be advised not only for epidemiological reasons, but also as an actual practical economic factor.In the past ten years attempts have been made to eliminate fowls reacting to tuberculin. This method has been moderately successful. We must hope also to direct our efforts to building up resistance to avian tuberculosis by some method of vaccination.In this paper we have presented experimental studies using heat-killed and living avirulent organisms to produce sensitization. Chickens sensitized with various types of dissociated avian tubercle bacilli may be thus made tuberculin hypersensitive. Those sensitized with heat-killed “R” developed a greater sensitiveness; those sensitized with heat-killed “S” reacted to a lesser degree. The heat-killed undissociated culture and the living “R” inoculated into fowls were allergic only for a short period and showed a lower intensity (see tables 1, 2, 3 and 4). So far as this experiment can be taken as an indication, a greater degree of protection was demonstrated in chickens vaccinated with heat-killed “S” organisms. In this group 28 out of 48 fowls were free from tuberculosis. Unfortunately, 8 out of 42 controls were free from tuberculosis. We cannot explain at present these negative results in the controls. Possibly the first attempt to give them an enteric infection gave them a resistance against the intravenous infection. It will be noted histological examination revealed greater calcification and healing in the vaccinated fowls and especially those vaccinated with heat-killed “S” organisms.

[学科分类] 生物科学（综合）