Biology of Calprotectin
Calprotectin is a very abundant neutrophil protein with many characteristics-
It constitutes more than 60% of total proteins in the cytosol of neutrophil granulocytes, each neutrophil contains 25 picograms of calprotectin compared to about 30 picograms haemoglobin per erythrocyte.
Calprotectin is released from activated leukocytes leading to increased concentrations in plasma, serum, spinal fluid, synovial fluid, urine, saliva or stools is increased during bacterial infections or inflammation in relevant organs.
Calprotectin is antimicrobial and has induced apoptosis in all cell types (human, animal, normal, malignant) tested. These effects can be reversed by addition of zinc. By binding zinc calprotectin can inhibit many important metalloproteinases.
Lack of calprotectin is not compatible with life.
CLINICAL ASPECTS OF CALPROTECTIN:
The Calprotectin syndrome presents with a clinical picture suggestive of zinc deficiency: children/young adults show growth retardation, bone marrow depression, immune deficiency, hepatosplenomegaly, arthritis and vasculitis; the concentration of calprotectin in their plasma is 2000 to 12000 times the normal. These huge amounts of calprotectin bind so much zinc that a functional zinc deficiency is created.
Calprotectin as a disease marker:
1) Body fluids: Increased concentrations will be found in response to infections and inflammation. Plasma calprotectin levels reflect disease activity in rheumatoid arthritis and LED better than ESR and CRP.
2) Stool samples: The PhiCal test™ for determination of faecal calprotectin concentrations has become a routine objective and non-invasive assay for detection of gastrointestinal inflammation or neoplasia and for assessment of inflammatory bowel disease activity and response to treatment. It can also predict the risk of relapse in patients in clinical remission; a normal PhiCal testTM is evidence that mucosal healing has been achieved. Use of the PhiCal testTM assists in selecting patients for endoscopy, in particular among children needing general anaesthesia.
Read more: The Calprotectin Company