The screening test for chemotherapeutic agents for leprosy

In view of the fact that there is no generally-accepted, uniform method for screening therapeutic agents for leprosy using murine leprosy, the methods used differing with each investigator so that the results are inconsistent, the need for a standard method was felt. Consequently, detailed basic studies were designed for the selection of a standard strain of murine leprosy for the purpose, the most suitable site of inoculation and quantity of inoculum to be used, the simplification and constancy of evaluation of results, and the selection of the best mouse strain. On the basis of the results of these studies a screening method, using the subcutaneous inoculation method, which might serve as a standard was devised.

Studies on the immunology of murine leprosy effects of vaccinations and previous infection

1- Injection of a saline vaccine of heat-killed murine leprosy bacilli some time prior to inoculation of live bacilli, causes inhibition of onset (prophylaxis) in a relatively high degree, although not totally. When the vaccine is given simulataneously with inoculation of live bacilli, there is a distinct but lesser degree of inhibition of onset. 2- Injection of a vaccine prepared by adding liquid paraffin to killed murine leprosy bacilli did not completely prevent infection by a challenge inoculation of live bacilli, but onset was strongly inhibited. The effect of this vaccine was stronger than that of the saline vaccine. 3- Administration of a liquid-paraffin vaccine of nonpathogenic acid-fast bacilli in place of murine leprosy bacilli resulted in a slight degree of immunity. 4- When secondary infection was attempted in rats already infected with murine leprosy, resistance greater than that induced by injectionnof the liquid paraffin vaccine was observed. When the challenge inoculum was a 0.5 cc. dose of a 10-4 leproma suspension, complete prevention was observed. 5- An acute reaction of the skin over the site of the reinoculation dose, resembling the Koch phenomenon in tuberculosis, was not observed. The size of the primary lesion did not influence the progress of the primary lesion. It is indicated that a certain degree of immunity can be attained by injection of killed or live murine leprosy bacilli in rats, and that it is also possible to obtain such an effect nonspecifically but in lesser degrees by injection of vaccines of other acid-fast bacilli.

Intracutaneous injection of acidomycin (Satanis method) in the treatment of leprosy

1- Acidomycin, a new antibiotic prepared in the Takata Laboratory, has been employed in the treatment of leprosy. 2- In this experiment the antibiotic was injected superficially into the leprous skin lesions, because when injected subcutaneously or intravenously acidomycin has shown no therapeutic effect in either tuberculosis or leprosy, although it is very active against the tubercle bacillus in vitro. 3- With intracutaneous application, on the contrary, there has been demonstrated a very interesting action. Where it was effective there was fading or disappearance of the macules and improvement or recovery of sensitivity. In certain cases there was decrease or disappearance of bacilli in the faded macules. 4- In several cases, lesions at a distance from those that were injected also showed improvement. In one of them a nodular auricularis magnus nerve became much reduced.