PATHOLOGY OF THE IMMUNE RESPONSE 



any drug or other causative factor, it seems likely that auto- 

 immune processes are involved but it has proved very 

 difficult to produce a reproducible method of demonstrating 

 platelet agglutinins or lysins. In Ackroyd's view only a very 

 small minority of the cases have been clearly shown to 

 possess a circulating agglutinin or lysin although it seems 

 likely that a relatively large proportion would be found to be 

 of auto-immune nature were appropriately sensitive and 

 reproducible tests available. 



On the clonal selection theory these cases would be classed 

 with the haemolytic anaemias as manifestations of casual 

 mutation in individuals where the homeostatic mechanism 

 was functioning inefficiently. The fact that they are not in- 

 frequently observed with the haemolytic anaemias adds 

 weight to this contention. 



An interesting condition, which presents some analogies 

 with sedormid purpura, has recently been described as an 

 unexpected result of incorporating zirconium salts into a 

 proprietary deodorant. A proportion of users developed 

 granulomatous lesions, a centimetre or two in diameter, in 

 the axilla. Shelley and Hurley (1957) have reproduced the 

 condition in one of ten volunteers who received small 

 multiple subcutaneous and intradermal injections of sodium 

 zirconium lactate. This subject showed a sudden appearance 

 of granulomatous lesions at each of the sites of inoculation 

 six months after the sensitizing injection. Similar granulo- 

 mata were produced by test inoculations of very small 

 amounts of zirconium salts in distant areas of skin. Biopsy 

 of the lesions showed histologically nests of epithelioid cells 

 with minimal round-cell infiltration, that is, an appearance 

 probably indistinguishable from a sarcoid nodule. 



One must assume that a zirconium-protein complex pro- 

 vides a new antigenic determinant and that when mesen- 

 chymal cells of a reactive clone reach an area containing 

 the determinant, their reaction is to proliferate locally 

 into an epithelioid nodule rather than give rise to the more 



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