Studies on bacterial hypersensitivity in man. Interrelationship between skin reactions to bacterial peptidoglycan and serum peptidoglycan antibody titers.

The nature and extent of bacterially induced allergies are difficult to define. Since peptidoglycan, the main component of the cell wall of almost all bacteria, has been available in a highly purified, chemically and immunologically well-defined form, investigation of the allergological significance of this cell component is feasible. Intracutaneous tests were carried out on 181 test, subjects with five different peptidoglycan (PG) preparations from Staphylococcus aureus, Staphylococcus epidermis and Staphylococcus pyogenes. The results of the investigation were compared with the result of determination of serum PG antibodies and serum IgE concentrations. It was shown that test subjects with dual and late reactions to three three different staphylococcal PGs displayed significantly higher PG antibody titers than test subjects with negative reactions. Such a relationship could not he found with the cutaneous reactions to streptococcal PG. The total serum IgE values were very much higher in test subjects with immediate reactions to staphylococcal PG than in test subjects with a negative reaction. Typical Arthus reaction or late granulomatous reactions were not observed. Humoral antibodies are involved at least in part in the elicitation of dual and late reactions. Thus, there are interesting parallels to allergy to fungal spores and organic dusts.