Antibody to streptococcal opacity factor in human sera

Maxted, W. R.; Widdowson, Jean P.; Fraser, Cherry A. M.

doi:10.1017/s0022172400046180

Cited by 24 publications

(19 citation statements)

References 9 publications

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“…None of the sera tested contained antibodies to OF from M-types 60 or 62. Within the population studied, antibodies to OF from M-type 25 were commonest (25), followed by types 4 (19), 22 (18), 2 (1 1), 9 and 48 (10 each), 49 (8) and 28,61,75 (three each) (table V). …”

Section: Resultsmentioning

confidence: 96%

Antibodies to streptococcal opacity factor in a selected Indian population

Prakash

Dutta²

1991

Journal of Medical Microbiology

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Summary. Antibody to at least one type of streptococcal opacity factor (OF) was present in 39.0% of 235 selected subjects and, in 4743% of these, to more than one type. Only 21.6% of children less than 4 years old had antibody to OF; these were to one type in 62.5% or to more than one in 37.5%. In the study group as a whole, the commonest antibodies were those to OF from M-serotype 25 followed, in descending order, by serotypes 4,22,2,9,48,49,28,61 and 75. Patients with rheumatic fever or rheumatic heart disease most often had antibodies to OF from M-types 25, 22, 4 and 9, whereas in patients with acute glomerulonephritis, antibodies to OF from M-types 48,49 and 61 were commonest. The limitations of the OFinhibition test as an epidemiological marker for prevalent M-types of group A streptococci are discussed.

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Section: Resultsmentioning

confidence: 96%

Antibodies to streptococcal opacity factor in a selected Indian population

Prakash

Dutta²

1991

Journal of Medical Microbiology

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“…The OF-neutralization test was performed in one of two ways: (1) by incorporating a hot-acid extract orbroth supernatant ofan OF-positive streptococcus, together with horse serum, in agar gel, pouring this as a thin layer on a large glass slide, and placing loopfuls of antiserum on the surface (Maxted et al 1973b); a circular area of clearing of opacity was a positive reaction; or (2) by incorporating an anti-OF antiserum and horse serum in the agar, and placing loopfuls of culture extract or supernatant on the surface (Maxted et al 1973a) (Maxted et al 1973a) was used to detect 'bactericidal' M antibody in the sera of human subjects. RESULTS …”

Section: Typing Of 8treptococcimentioning

confidence: 99%

“…Anti-OF sera were either (1) stock M antisera that had been found to have opacity neutralizing activity against streptococci of corresponding M type, (2) rabbit antisera prepared specifically for the opacity-neutralization test (Maxted et al 1973b), (3) pooled antisera prepared by intraperitoneal inoculation of streptococci into guinea-pigs (Maxted, unpublished), or human sera found to have typespecific opacity-neutralizing activity (Maxted et al 1973a).…”

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confidence: 99%

Serological characterization of group-A streptococci associated with skin sepsis in meat handlers

Fraser

Ball

Morris

et al. 1977

J. Hyg.

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SUMMARYA series of outbreaks of skin sepsis among meat handlers in England during 1974 and 1975 afforded an opportunity to study the group-A streptococci commonly isolated from the lesions. Few of these streptococci could be M typed with existing antisera. Intensive study of strains from two outbreaks of sepsis in one abattoir in Shropshire led to the recognition of three new provisional M types. The streptococci were first sorted according to T-typing pattern and ability to produce opacity factor. Opacity-factor producing strains with the same T pattern were then screened for inhibition of opacity production by the sera of convalescents from the same outbreak. Finally, M antisera were made in rabbits against representative cultures.Sera against the three new provisional types were used to re-examine streptococci from 20 other outbreaks or incidents of sporadic infection among meat handlers. This increased the proportion of typable strains from 3 % to 55 %. Two of the new provisional types (nos. 2015 and 1658; both T25/Imp 19, opacityfactor positive) were confined to the Shropshire outbreak, but the third (no. 2681; T14, opacity-factor negative) was found among strains from meat workers in eight other geographically distinct areas. In all, 31 % of 131 distinct strains from meat workers, but less than 1 % of 2816 strains from other British sources, belonged to provisional type 2681. Thus, in Britain, one M-type of group-A streptococcus appears at present to be almost exclusively associated with sepsis in meat workers.

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“…OF antibody was not detected in more than half of all the M-antisera prepared for OF-positive serotypes. However, investigation of the time-course of antibody formation indicated that when anti-OF was formed it was often detected before antibodies to the M protein (Maxted, Widdowson and Fraser, 1974). Some sera contained M antibody but no OF antibody at the same stage of immunisation and others contained antibody to M and to OF antigens simultaneously.…”

Section: Discussionmentioning

confidence: 99%

Preparation of Specific Antisera to the Opacity Factors of Group-A Streptococci

Fraser

1982

Journal of Medical Microbiology

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SUMMARY. Type-specific antibody to the opacity factor (OF) of group-A streptococci can be demonstrated in human sera but the multiplicity of antibodies to different serotypes limits their usefulness in anti-OF typing. The antibody response in rabbits is inconsistent; only 61 of 138 (44%) of rabbit anti-M sera tested contained OF antibody. Of these only about half had titres of > 16, and usable sera to only I 1 of 23 OF-positive serotypes were obtained. On the other hand good anti-OF sera (titres > 16) to 27 of 28 serotypes resulted from the interperitoneal and subcutaneous inoculation of heat-killed whole-cell vaccines in guinea-pigs and the frequency of response in groups of animals given injection of the same vaccine was 100% for all but three serotypes. Antibody response was not obtained with M-type 13. A comparison of routes of inoculation for M-type 25 showed that the subcutaneous route alone could probably be used in the routine production of anti-OF typing sera. Use of the set of 27 sera in OF-inhibition tests confirmed the remarkable specificity of OF antigens and their parallelism with M-antigen specificity, with the exception of a reciprocal cross reaction between M-type 61 and provisional type PT3875.

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Antibody to streptococcal opacity factor in human sera

Cited by 24 publications

References 9 publications

Antibodies to streptococcal opacity factor in a selected Indian population

Antibodies to streptococcal opacity factor in a selected Indian population

Serological characterization of group-A streptococci associated with skin sepsis in meat handlers

Preparation of Specific Antisera to the Opacity Factors of Group-A Streptococci

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