Acute rheumatism in children in its relation to heart disease.

Date:
1927
Catalogue details

Licence: Public Domain Mark

Credit: Acute rheumatism in children in its relation to heart disease. Source: Wellcome Collection.

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    the parallel specific agglutination. Absorption experiments showed that the two antibodies in antibacterial sera were immunologically distinct.”’ Immunisation experiments were also made with P and with S. With the latter substance, the attempt to produce antibodies in a rabbit failed. ‘“‘ At no time during immunisation could §S antibodies be demonstrated in the serum of this animal, although the material injected contained in solution all the 8 obtainable by this method from the bacterial sediment of 7 litres of original broth culture. This is at least indirect evidence that S from non- haemolytic streptoccoci does not, after dissociation from the cell, lead to antibody production.’ Immunisation with P gave rise to antibodies which reacted only with nucleoproteins. ‘‘ The six rabbits immunised with nucleoprotein received. between twenty- five and thirty intravenous injections over periods of 6 to 8 weeks. No S antibodies appeared in their sera.” The P antibodies pro- duced in this way were “ little, if at all, concerned in causing agglutination.”” They were relatively non-specific and showed group reactions with nucleoproteins of related species. Lancefield’s results bear a fairly close resemblance to what has been found on a larger scale with pneumococci and show that the antigenic analysis of viridans is a serious undertaking. The two most conspicuous difficulties are the diversity of the S elements and the possible confusion between “ group”’ and ‘“ specific ’’ reactions when using sera which contain both P and S antibodies. As her detailed analysis was confined to four strains, the question arises whether application of her methods to a much larger number would reveal some tendency to a distribution into types, just as an investigator might find his first four strains of pneumococci from pneumonia all different antigenically but, if he went on to examine forty, he would certainly be able to class many of them into groups or types. At the present time, enough work has not been done to justify a decisive answer to this question. The indications are that the reply will probably be more or less definitely in the negative. Hitchcock!’ (1924) extracted a soluble precipitating substance from non-haemolytic streptococci and used this material as antigen in precipitation and complement fixation tests. His antisera were prepared by immunising rabbits with whole cultures injected intravenously. He found that his strains were an “entirely heterogeneous group’ and also remarked that ‘“‘such cross-reactions as do occur within this group are not useful in the systematic classification of these organisms.’ His strains were 12 in number, 3 from blood cultures in rheumatic fever, 1 from a heart valve in rheumatic endocarditis, 4 from blood cultures in bacterial endocarditis, 2 from normal throats, 1 from sputum in bronchial asthma, and 1 from sputum in bronchopneumonia. It must not be forgotten that information on this subject may also be gained from many of the bacteriologists who have attempted a serological classification of viridans by use of the te