Related Experiment Video
Updated: Jun 12, 2026
07:26
Isolation of Functional Cardiac Immune Cells
Published on: December 5, 2011
Human cardiac mast cells in anaphylaxis
Chemical Immunology and Allergy
|June 4, 2010
Summary
Human heart mast cells (HHMC) are key players in anaphylaxis, releasing mediators that affect heart function. These cells can be activated by allergens and medical agents, potentially causing anaphylactoid reactions.
Area of Science:
- Immunology
- Cardiology
- Cell Biology
Background:
- Human heart mast cells (HHMC) are implicated as primary effector cells in anaphylaxis.
- These cells are located perivascularly, near myocytes, and in the arterial intima of human heart tissue.
- HHMC express high-affinity IgE (FcepsilonRI) and C5a receptors.
Purpose of the Study:
- To investigate the role and activation mechanisms of human heart mast cells in anaphylaxis.
- To determine the mediators released by HHMC upon activation.
- To assess the potential of HHMC to mediate anaphylactoid reactions.
Main Methods:
- Isolation and in vitro activation of human heart mast cells (HHMC).
- Stimulation of HHMC using anti-IgE, anti-FcepsilonRI, and C5a.
- Measurement of preformed and newly synthesized mediators (histamine, tryptase, LTC4, PGD2).
- Evaluation of HHMC activation by therapeutic and diagnostic agents.
Main Results:
- HHMC activation released preformed mediators (histamine, tryptase, chymase, renin) and synthesized LTC4 and PGD2.
- C5a induced rapid release of histamine and tryptase from HHMC.
- HHMC were activated in vitro by general anesthetics, protamine, and radiocontrast media.
- Histamine and cysteinyl leukotrienes caused significant hemodynamic effects in subjects.
Conclusions:
- Human heart mast cells play a significant role in anaphylactic and anaphylactoid reactions.
- HHMC activation by various agents can lead to mediator release with hemodynamic consequences.
- These findings highlight the importance of HHMC in cardiovascular responses during anaphylaxis.
Related Concept Videos
01:30Allergic Reactions: Anaphylaxis
Anaphylaxis is a severe, life-threatening hypersensitivity reaction mediated by Immunoglobulin E (IgE) antibodies. When IgE binds to allergens, it triggers the release of mediators– histamine, leukotrienes, and prostaglandins from mast cells and basophils. These mediators cause vasodilation, edema, and inflammation, leading to various symptoms.The primary allergens causing anaphylaxis include food items (e.g., peanuts, shellfish), drugs (e.g., penicillin, asparaginase, corticotropin, heparin),...
02:06Allergic Reactions
Overview
01:30Hypersensitivities
Hypersensitivity, also known as a hypersensitivity reaction or allergic reaction, is a condition where the body's immune system reacts abnormally to a foreign substance. Such substances, that cause hypersensitivity are referred to as an allergen, could be something typically harmless to most people, like pollen or certain foods.
Types of Hypersensitivities
Hypersensitivity reactions are categorized into four types: Type 1, Type 2, Type 3, and Type 4. Each type has a distinct mechanism...
Types of Hypersensitivities
Hypersensitivity reactions are categorized into four types: Type 1, Type 2, Type 3, and Type 4. Each type has a distinct mechanism...
01:38Inflammation
Overview
01:25Antiasthma Drugs: Mast Cell Stabilizers and Anti-IgE Drugs
Asthma is a chronic respiratory condition for which new therapeutic avenues, including anti-inflammatory drugs like mast cell stabilizers and anti-IgE treatments, continue to be developed.
Mast cell stabilizers, such as cromolyn (also known as sodium cromoglycate) and nedocromil (Tilade), are effective drugs in asthma management. These stabilizers hinder histamine release by skillfully obstructing the activation of mast cells and other cellular entities. Notably, they navigate this task without...
Mast cell stabilizers, such as cromolyn (also known as sodium cromoglycate) and nedocromil (Tilade), are effective drugs in asthma management. These stabilizers hinder histamine release by skillfully obstructing the activation of mast cells and other cellular entities. Notably, they navigate this task without...
01:30Drug Toxicity: Allergic Reactions
Drug-related allergies are immune-mediated responses triggered by the administration of pharmacological agents. These hypersensitivity reactions are classified based on the immune mechanisms involved. The four primary types—Type I, II, III, and IV—are mediated by different immunological pathways and exhibit distinct clinical manifestations.Type I Hypersensitivity/ IgE-Mediated Reactions: Immunoglobulin E (IgE) immediately mediates Type I hypersensitivity reactions. Upon initial exposure to a...