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- Christensen, P, et al.
(författare)
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Demonstration of the non-identity between the Fc receptor for human IgG from group A streptococci type 15 and M protein, peptidoglycan and the group specific carbohydrate
- 1979
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Ingår i: Acta Pathologica et Microbiologica Scandinavica. Section C, Immunology. - 0304-1328. ; 87C:3, s. 61-257
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Tidskriftsartikel (refereegranskat)abstract
- After electrophoresis of an alkaline extract of type 15 group A streptococci, three main precipitation lines were obtained in diffusion experiments against commercial human polyclonal IgG (lines 1, 2 and 3). Nineteen of 23 sera (83%) from apparently healthy human individuals gave line 3, while 6 of them (26%) gave line 1. The sera giving line 1 did also give line 3. Line 2 was obtained with 2 sera only, also giving lines 1 and 3. Line 3 was caused by a streptococcal Fc-receptor for human IgG, since the line could be displaced by addition of Fc-fragments, but not Fab-fragments of pooled human IgG. Line 1 was shown to be different from line 3, since (1) line 1 was suppressed in contrast to line 3 on absorption of a human serum or commercial polyclonal human IgG with S. aureus; and (2), line 1 was suppressed by Fab-fragments but not Fc-fragments of polyclonal human IgG. Line 2 could be inhibited by addition of peptidoglycan to commercial polyclonal human IgG or a human serum investigated. Another line, 4, obtained in diffusion experiments involving electrophoretically separated alkaline extract of type 15 group A streptococci was type-specific as shown by rabbit antisera to streptococci type M1, M8, M15, and T44, and disappeared on trypsinization of the extract. The component responsible for line 4 in the streptococcal extract, judged to be type-specific M protein, had a mobility different from the component responsible for line 3 in electrophoresis.
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| 2. |
- Christensen, P, et al.
(författare)
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Interaction of the Fc part of IgG with Lancefield extracts of hemolytic streptococci. Strain specificity and activity
- 1979
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Ingår i: Acta Pathologica et Microbiologica Scandinavica. Section C, Immunology. - 0304-1328. ; 87C:1, s. 7-73
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Tidskriftsartikel (refereegranskat)abstract
- Lancefield extracts of 19 types of group A streptococci as well as one group C and one group G strain were examined for agglutination of human red cells coated with various anti-Rh antibodies. Fourteen extracts agglutinated one or more of the coated cell samples, while five did not. The agglutination was inhibited by Fc but not by Fab fragments of human IgG. After mouse passages, three of the non-agglutinating strains acquired agglutinating capacity. At least three different reactivities were distinguished by the action of the extracts on IgG1 and IgG3 coated cells, respectively. Two of the streptococcal extracts, agglutinating the same anti-Rh coated cells, could be further differentiated in hemagglutination inhibition (HAI) experiments using purified IgG3 myeloma proteins. Five selected agglutinating systems were inhibited by purified myeloma proteins of the IgG1, IgG2, and IgG4 subclasses. IgG3 proteins inhibited only two of the five HAI systems.
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