basophil

Function

• immediate hypersentitivity reactions
• some delayed hypersensitivity reactions
• basophils granules contain
  • histamine
  • eosinophil chemotactic factor-A (ECF-A)
  • heparin
  • peroxidase
• basophils also synthesize & release
  • slow-reacting substance of anaphylaxis (SRS-A)
  • platelet-activating factor (PAF)

Biochemistry

• mature basophils express CD32
• basophils bind IgE
• antigen binding basophil-bound IgE results in degranulation of basophils with release of histamine, ECF-A, heparin, peroxidase, SRS-A, PAF
• this results in accumulation of eosinophils which contain substances that tend to counteract the effects of basophils

Physiology

• basophils develop from a progenitor cell resembling a myeloblast separate from neutrophil, monocyte, eosinophil progenitors
• the earliest recognizable basophil precursor is the basophilic meylocyte
• maturation time in the bone marrow is ~ 7 days
• life span in peripheral blood is similar to eosinophils (~ 18 hours)
• basophils are not found in tissues
• basophils do not seem to give rise to mast cells

Laboratory

• component of complete blood count with differential
• normal basophil count is 0-100/uL, & 0.4% of circulating WBC
• labs with Loincs
  • basophils in specimen
    • basophils in nose
    • basophils in body fluid
      • basophils in amniotic fluid
      • basophils in blood
        • basophils in cord blood
      • basophils in bronchial fluid
      • basophils in CSF
      • basophils in dialysis fluid
      • basophils in pericardial fluid
      • basophils in peritoneal fluid
      • basophils in pleural fluid
      • basophils in sputum
      • basophils in synovial fluid
      • basophils in vitreous fluid

More general terms

• granulocyte

Additional terms

• basophilia
• basophils in blood