Neutrophils 3 Flashcards
What types of cells can be affected by LADs (Leukocyte Adhesion Defects)?
Neutrophils
Eosinophils
Basophils
Monocytes
What is wrong in Leukocyte Adhesion Deficiency Type I (LAD1)?
The integrin on the blood vessel endothelium is defective (Integrins are transmembrane receptors that facilitate cell-cell and cell-extracellular matrix adhesion)
- They are composed of CD18 and CD11
- CD 18 is defective
What is wrong in Leukocyte Adhesion Deficiency Type 2 (LAD2)?
It’s a problem with “cell rolling” which slows the cell down. Leukocytes contain an oligosaccharide on their surface called L-selectin (AKA CD62-L) which is defective. It has trouble binding on to the selectin on the surface of the endothelial cell
What is the structural problem in Chediak-Higashi syndrome?
The microtubule system connecting the phagosome and lysosome is defective. This leads to a problem with phagocytosis
What is the basic pathophysiology of chronic granulomatous disease?
Phagocytes have defective NADPH oxidase and can’t produce ROS
What types of infections are patients with chronic granulomatous disease susceptible to and what forms as a result?
Bacterial and fungal infections
Granulomas form in the GI and GU tracts but can form in lungs and many other areas
How can some patients with chronic granulomatous disease (impaired NADPH oxidase) still produce ROS in their neutrophils?
How do some bacteria get around this?
- Most living organisms (including bacteria) produce H2O2 which the neutrophil will use to produce bleach (which kills the bacteria that it got the H2O2 from)
- They produce their catalase which breaks down the H2O2
Neutrophil and macrophage. Which produces pus and which produces granulomas?
Neutrophil = pus
Macrophage = granuloma
Why is neutrophil function impaired in diabetics?
- There is less glucose in the neutrophil which impairs its function
- The acidotic environment associated with diabetes impairs its function
