Basophils

Definition

Basophils are a type of white blood cell that play a crucial role in the body's immune response. They are the least common type of granulocyte, but their unique characteristics and functions make them an important component of the innate immune system.

5 Must Know Facts For Your Next Test

1. Basophils are responsible for initiating and amplifying the inflammatory response, particularly in allergic reactions.
2. Basophils express high-affinity receptors for the Fc region of IgE antibodies, allowing them to be activated by allergens.
3. Upon activation, basophils release a variety of potent inflammatory mediators, including histamine, leukotrienes, and cytokines.
4. Basophils play a role in the body's defense against parasitic infections, contributing to the expulsion of parasites from the body.
5. Increased numbers of basophils in the blood (basophilia) can be a sign of certain medical conditions, such as allergies, asthma, and myeloproliferative disorders.

Review Questions

• Describe the key functions of basophils in the immune system.
  • Basophils are essential for the body's inflammatory and allergic responses. They express high-affinity receptors for IgE antibodies, allowing them to be activated by allergens. Upon activation, basophils release a variety of potent inflammatory mediators, such as histamine, leukotrienes, and cytokines, which contribute to the symptoms of allergic reactions and help expel parasitic infections from the body. Basophils play a crucial role in initiating and amplifying the inflammatory response, making them an important component of the innate immune system.
• Explain the relationship between basophils and mast cells, and how they differ in their functions.
  • Basophils and mast cells are both granulocytes that contain granules filled with inflammatory mediators, such as histamine. While both cell types contribute to the body's inflammatory and allergic responses, they have some key differences. Basophils are circulating white blood cells that are involved in the systemic immune response, while mast cells are tissue-resident cells that primarily function in the local immune response. Mast cells are more numerous and are found in various tissues, particularly those exposed to the external environment, such as the skin and mucous membranes. Basophils, on the other hand, are less common and are primarily found in the blood and lymph. Despite these differences, both basophils and mast cells play complementary roles in the body's defense against allergens and parasitic infections.
• Discuss the clinical significance of basophilia, and how it can be used as a diagnostic marker for certain medical conditions.
  • Basophilia, or an increased number of basophils in the blood, can be a useful diagnostic marker for various medical conditions. Elevated basophil counts are often associated with allergic disorders, such as asthma, eczema, and certain types of urticaria (hives). Basophilia can also be a sign of myeloproliferative disorders, which are a group of conditions characterized by the overproduction of certain blood cells, including basophils. In these cases, basophilia may be an early indicator of the disease and can help guide further diagnostic testing and treatment. Additionally, basophilia can be observed in parasitic infections, as the body's immune system mobilizes basophils to help expel the parasites. By monitoring a patient's basophil levels, healthcare providers can gain valuable insights into the underlying cause of the patient's symptoms and tailor their treatment approach accordingly.

Related terms

Granulocytes: A type of white blood cell that contains granules in their cytoplasm, including basophils, eosinophils, and neutrophils.

Histamine: A chemical released by basophils and mast cells that causes blood vessels to dilate and smooth muscles to contract, leading to inflammation and allergic responses.

Mast Cells: Tissue-resident cells that, like basophils, contain granules filled with histamine and other inflammatory mediators.