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Updated: Sep 25, 2026
Isolation of Peritoneum-derived Mast Cells and Their Functional Characterization with Ca2+-imaging and Degranulation Assays
Published on: July 4, 2018
Intestinal mucosa-associated bacteria modulate rat mast cell reactivity
E Brzezińska-Blaszczyk1, A K Olejnik
1Division of Experimental Immunology, Medical University of Łódź, Poland. ewab@psk2.am.lodz.pl
Abstract:
It is well known that in some conditions bacteria of physiological flora of gastrointestinal tract may become pathogenic. Each complaint which causes injury of gastrointestinal wall integrity permits bacteria to penetrate the tissues and affect the tissue cells. Since mast cells represent one of very important and numerous cellular elements of the gastrointestinal tract walls, bacteria can exert the effects on them. Therefore, the aim of our study was to examine the influence of four strains of intestinal mucosa-associated bacteria--Bacteroides thetaiotaomicron, Bacteroides fragilis, Bifidobacterium adolescentis and Escherichia coli on the mast cell reactivity. Our experiments were performed in vitro on isolated rat peritoneal mast cells and the reactivity of these cells was estimated on the basis of histamine release. We used the suspensions of whole bacteria, killed by heating at 65 degrees C. We have noticed that the magnitude of bacteria-induced histamine release from mast cells was very low (up to 6.0%) when compared with histamine release induced with Con A, compound 48/80 and TNF-alpha. However, all studied bacteria changed the reactivity of mast cells in anaphylactic (with ConA) and anaphylactoid (with compound 48/80) reactions. After 40 min preincubation with B. thetaioataomicron, B. fragilis, B. adolescentis or E. coli ConA-induced histamine release was diminished up to 25%, 71%, 58% and and 68% of maximal histamine release, respectively. Preincubation of rat mast cells with B. thetaioataomicron, B. fragilis, B. adolescentis or E. coli also changed their reactivity in anaphylactoid reaction with compound 48/80 (histamine release was diminished up to 70%, 63%, 63% and 60%, respectively).
Insights
Intestinal bacteria, including Bacteroides and E. coli, can alter mast cell reactivity. This study found these bacteria significantly reduced histamine release in rat mast cells during allergic and anaphylactoid reactions.
Area of Science:
- Gastroenterology
- Immunology
- Microbiology
Background:
- Physiological gut flora can become pathogenic, especially when gastrointestinal wall integrity is compromised.
- Mast cells are crucial cellular components of the gastrointestinal tract walls and are targets for bacterial interactions.
- Understanding these interactions is vital for comprehending gut health and disease.
Purpose of the Study:
- To investigate the impact of four specific intestinal mucosa-associated bacteria on mast cell reactivity.
- To analyze the effects of Bacteroides thetaiotaomicron, Bacteroides fragilis, Bifidobacterium adolescentis, and Escherichia coli on mast cell degranulation.
Main Methods:
- In vitro study using isolated rat peritoneal mast cells.
- Bacterial strains were killed by heat (65°C) and used as suspensions.
- Mast cell reactivity was assessed by measuring histamine release, comparing bacterial effects to known histamine releasers (Con A, compound 48/80, TNF-alpha).
Main Results:
- Bacteria-induced histamine release was minimal (up to 6.0%) compared to standard agonists.
- All tested bacteria (B. thetaiotaomicron, B. fragilis, B. adolescentis, E. coli) significantly modulated mast cell reactivity.
- Preincubation with bacteria diminished ConA-induced (anaphylactic) histamine release by 25-71% and compound 48/80-induced (anaphylactoid) histamine release by 60-70%.
Conclusions:
- Intestinal bacteria, even at low direct histamine release levels, can significantly alter mast cell responsiveness.
- These findings highlight a potential mechanism by which gut microbiota influences inflammatory and allergic responses in the gastrointestinal tract.
- Further research is warranted to explore the clinical implications of these microbial-mast cell interactions in gut health.
