title: Lipoproteinase of group A streptococci and the antibodies in human sera.
abstract: The possibility of revealing lipoproteinase (serum opacity factor--OF) in hydrochloric and alkaline extracts from streptococcal cultures and the possibility of concentration and purification of this enzyme by means of gel-filtration and ion-exchange chromatography have been confirmed. When studying antibodies to OF in the blood of healthy and sick people, we were able both to reveal and to determine the titre of antibodies to OF of different serological M types (2, 4, 22/12, 22 and 49) in the sera under study (170 sera from the same number of persons). In groups of healthy people, anti-OF antibodies were shown to be present with a high frequency as well as in patients. But the titres of antibodies in the former were lower than in the latter. Most sera (32%) neutralized OF of one serological type and only 3% all types of enzymes used. The type-specificity of the anti-OF antibodies was shown. The data obtained are yet insufficient for epidemiological or clinical analysis but they point out the possibility of using the anti-OF test for these purposes.
mesh_terms: D000293:Adolescent; D000328:Adult; D000907:Antibodies, Bacterial / Q000032:analysis*; D000918:Antibody Specificity; D002648:Child; D006801:Humans; D008071:Lipoprotein Lipase / Q000276:immunology / Q000302:isolation & purification*; D009500:Neutralization Tests; D013290:Streptococcal Infections / Q000276:immunology; D013291:Streptococcus / Q000201:enzymology / Q000276:immunology*
chemical_list: D000907:Antibodies, Bacterial; D008071:Lipoprotein Lipase