Penicillin, immunogen preparation

In summary, it seems firmly established that penicillin polymers, and especially polymers formed from aminopenicillins, exhibit a strong penicilloyl-specific antigenicity and it is likely that they may play a part in the elicitation of some clinical allergic reactions to penicillin preparations. The question of immunogenicity of penicillin polymers is still to be fully resolved. 

Bundgaard H (1977 d) 4-Hydroxyphenylbutazone a potentially immunogenic contaminant of phenylbutazone preparations. Arch Pharm Chem Sci 5 87-96 Bundgaard H (1977 e) Quantitative determination of amino-penicillins in the presence of their degradation and polymerization products. Arch Pharm Chem Sci 5 141-148... 

The chemical routes to the formation of the penicilloyl determinant can be multiple and have been the subject of some controversies. It has been claimed that the main source of immunogenic penicilloyl antigens leading to penicillin sensitization in therapy is the presence of penicilloylated protein impurities in most penicillin preparations. This topic is discussed extensively in Sect. 1.9. 

While 6-APA itself plays no chnical role, the amount of protein impurities surviving the manufacturing processes of semisynthetic penicillins, for which 6-APA is the base material, still represents a problem of major clinical significance. Every effort should be made to prepare semisynthetic penicillins substantially free of immunogenic protein contaminants. The determination of the amounts of protein impurities surviving the current manufacturing processes is fraught with difficulties, as pointed out by several authors (Ottens et al. 1971 Walsh et al. 1971). 

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