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Humanized Mouse Model to Study Bacterial Infections Targeting the Microvasculature
Published on: April 1, 2014
Effect of Bacteroides fragilis on the human erythrocyte membrane: pathogenesis of Tk polyagglutination
Journal of Clinical Pathology
|December 1, 1975
Abstract:
Incubation of normal human erythrocytes with the supernatant of centrifuged culture of some strains of Bacteroides fragilis results in the exposure of Tk polyagglutination determinants on the erythrocyte membrane. These determinants are present on non papain-labile structures and are probably exposed by an enzyme mechanism. Other strains of B. fragilis were found to produce neuraminidase, haemolysins, and protease. It is suggested that early recognition of Tk determinants may be an aid to the diagnosis of B. fragilis infection.
Insights
Bacteroides fragilis infection can be diagnosed by detecting Tk determinants on red blood cells. These determinants are exposed by bacterial enzymes, offering a potential diagnostic marker.
Area of Science:
- Microbiology
- Immunology
- Hematology
Background:
- Bacteroides fragilis is an opportunistic pathogen.
- Erythrocyte surface antigens can be modified by bacterial products.
- Tk polyagglutination determinants are typically not expressed on normal erythrocytes.
Purpose of the Study:
- To investigate the effect of Bacteroides fragilis supernatant on human erythrocyte membranes.
- To identify the mechanism of Tk determinant exposure.
- To explore the diagnostic potential of Tk determinants in B. fragilis infections.
Main Methods:
- Incubation of normal human erythrocytes with centrifuged culture supernatant of B. fragilis strains.
- Analysis of erythrocyte membrane structures for Tk determinant exposure.
- Testing for enzymatic activities (neuraminidase, haemolysins, protease) in bacterial supernatant.
Main Results:
- Supernatant from certain B. fragilis strains induced Tk polyagglutination determinant exposure on erythrocytes.
- Tk determinants were found on non-papain-labile structures, suggesting enzymatic exposure.
- Other B. fragilis strains produced neuraminidase, haemolysins, and protease.
Conclusions:
- Bacteroides fragilis can expose Tk polyagglutination determinants on erythrocytes via enzymatic mechanisms.
- Early recognition of Tk determinants may serve as a diagnostic aid for B. fragilis infections.
- Further research is warranted to validate Tk determinants as a reliable diagnostic marker.
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