Mast cells

  • Mast cells were first described by Paul Ehrlich in his 1878 doctoral thesis on the basis of their unique staining characteristics and large granules
  • A mast cell is also known as Mastocyte and Labrocyte
  • The cells contains many granules rich in Histamine and Heparin
  • Mast cells play a key role in the inflammatory process
  • These cell precursors are formed in the bone marrow by hematopoiesis.  mast cell
  • Mast cells known for their role in Allergy and Anaphylaxix.
  • The major function of Mast cells are involved in Wound Healing  and Defense against Pathogens.
  • The mast cell is very similar in both appearance and function to the basophil, a type of white blood cell
  • These are found in a wide variety of tissues, including The skin.Connective tissues of various organs, Mucosal epithelial tissue of respiratory, Genitourinary & digestive tracts.
  • These cells have large number of cytoplasmic granules that contain "Histamine" and other pharmacologically active Substances. 
  • It plays an important role in the development of allergies

 

Role in disease

Allergic disease

Many forms of cutaneous and mucosal allergy are mediated for a large part by mast cells; they play a central role in asthma, eczema, itch (from various causes) and allergic rhinitis and allergic conjunctivitis. Antihistamine drugs act by blocking the action of histamine on nerve endings. Cromoglicate-based drugs (sodium cromoglicate, nedocromil) block a calcium channel essential for mast cell degranulation, stabilizing the cell and preventing release of histamine and related mediators. Leukotriene antagonists (such as montelukast and zafirlukast) block the action of leukotriene mediators, and are being used increasingly in allergic diseases.

Anaphylaxis

In anaphylaxis (a severe systemic reaction to allergens, such as nuts, bee stings or drugs), body-wide degranulation of mast cells leads to vasodilation and, if severe, symptoms of life-threatening shock.

Autoimmunity

Mast cells are implicated in the pathology associated with the autoimmune disorders rheumatoid arthritis, bullous pemphigoid, and multiple sclerosis. They have been shown to be involved in the recruitment of inflammatory cells to the joints (e.g. rheumatoid arthritis) and skin (e.g. bullous pemphigoid) and this activity is dependent on antibodies and complement components.

Reproductive disorders

Mast cells are present within the endometrium, with increased activation and release of mediators in endometriosis. In males, mast cells are present in the testes and are increased in oligo- and azoospermia, with mast cell mediators directly suppressing sperm motility in a potentially reversible manner.

Mast cell disorders

Mastocytosis is a rare condition featuring proliferation of mast cells. It exists in a cutaneous and systemic form, with the former being limited to the skin and the latter involving multiple organs. Mast cell tumors are often seen in dogs and cats.

Watch this Video on MAST CELLS:

 

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