What are the functions of granules present in eosinophil???
Two types of granules are present in eosinophils:
1.Azurophilic granules which are present in all granulocytes and contain acid hydrolases and other enzymes.
2.Specific granules contain four major proteins: Major basic protein (MBP) found in the crystalloid bodies, and then eosinophil cationic protein (ECP), eosinophil peroxidise (EPO) and eosinophil derived neurotoxin (EDN) which are all found in the granule matrix. Substances such as histaminases, cathepsins (proteases) and collagenases are also present.
Functions of these granules are given below-
Anti-parasitic:
Fc receptors on eosinophils allow them bind to parasites coated in antibodies and once bound they degranulate. The specific granules release EDN which interferes with the parasitic nervous system while MBP, ECP and EPO (EPO dissolves the carbohydrate coat of the parasite) all have anthelmintic and anti-protozoal actions. These proteins act as stimulants to mast cells causing them to release histamine and thus attracting more eosinophils. However, they also damage the animal’s tissue as well as the parasites.
Allergic:
Histaminases in the specific granules breaks down histamine produced by mast cells while arylsulfatase breaks down leukotrienes. The products of these breakdowns further attracts more eosinophils.
Okk…thats it for now…If you find it helpful,then dont forget to share it with others…and follow our page Pathology Discussion Forum to get our upcoming videos/ articles instantly!!!
