Related Experiment Video
Updated: Jun 19, 2026
05:19
Imaging Flow Cytometry to Study Microbial Autoaggregation
Published on: September 29, 2023
FURTHER OBSERVATIONS ON THE AGGLUTINATION OF BACTERIA IN VIVO
1Laboratories of The Rockefeller Institute for Medical Research.
The Journal of Experimental Medicine
|October 30, 2009
Summary
Bacterial agglutination and opsonization in vivo vary based on host immunity and bacterial virulence. Highly virulent bacteria show less agglutination/opsonization, indicating inverse correlation with infectiousness.
Area of Science:
- Immunology
- Microbiology
- Bacteriology
Background:
- Bacterial agglutination and opsonization are key immune responses.
- Understanding these processes in vivo is crucial for infectious disease research.
- Host-pathogen interactions influence immune mechanisms.
Purpose of the Study:
- To investigate bacterial agglutination and opsonization in the circulation of normal and actively immunized rabbits.
- To evaluate the effects of Bacillus avisepticus on rabbits and dogs, including serum bactericidal and opsonic activity.
- To determine the relationship between bacterial infectiousness and in vivo immune responses.
Main Methods:
- Injection of various bacterial species into the circulation of immunized and normal rabbits.
- Administration of Bacillus avisepticus cultures to rabbits and dogs.
- Assessment of bacterial agglutination, opsonization, and bactericidal activity in animal sera and circulation.
- Evaluation of septicemia development and host response.
Main Results:
- Actively immunized rabbits showed immediate agglutination of specific bacteria (Pneumococci, Shiga's dysentery bacilli, B. mucosus capsulatus).
- Normal rabbits exhibited agglutination of Staphylococcus aureus/albus, colon bacilli, meningococci, gonococci, and non-virulent pneumococci.
- Bacillus avisepticus was toxic to rabbits and dogs; dog serum showed opsonic and agglutinating activity in vivo, unlike rabbit serum. Rabbits developed fatal septicemia, while dogs tolerated subtoxic doses.
- A clear inverse correlation was observed between the degree of in vivo bacterial agglutination/opsonization and the infectiousness of the bacteria for the host.
Conclusions:
- Host immune status significantly impacts bacterial agglutination and opsonization.
- Bacillus avisepticus exhibits differential pathogenicity and host immune interaction between rabbits and dogs.
- In vivo bacterial agglutination and opsonization serve as indicators of bacterial infectiousness and host defense effectiveness.
Related Concept Videos
01:26Antibody Actions
Antibodies, or immunoglobulins, are critical players in the immune system's arsenal against invading pathogens. Produced by B cells and plasma cells, their primary role is to detect and bind to specific antigens, molecules found on the surface of pathogens like bacteria or viruses. Beyond antigen recognition, antibodies perform several vital functions that contribute to immune defense.
Neutralization
Antibodies can bind to pathogens, preventing them from infecting host cells. This process...
Neutralization
Antibodies can bind to pathogens, preventing them from infecting host cells. This process...
02:45Blood Transfusion and Agglutination
Blood transfusion is a therapeutic measure to restore the blood volume after extensive blood loss due to an accident or a medical procedure. Blood transfusion involves drawing a certain amount of blood from a suitable donor and infusing it into the recipient.
History
The history of blood transfusion dates back to the 17th century, when early attempts were made in animals. In 1818 James Blundell, a British doctor, performed the first successful human blood transfusion. Later in 1900, Karl...
History
The history of blood transfusion dates back to the 17th century, when early attempts were made in animals. In 1818 James Blundell, a British doctor, performed the first successful human blood transfusion. Later in 1900, Karl...