Acute phase reactants

Question 1

What are acute phase reactants?

Answer 1

Proteins whose serum concentrations increase or decrease by at least 25 percent during inflammatory states

Question 2

What can acute phase reactants be divided into?

Answer 2

Such proteins are termed either positive or negative acute phase reactants (APR),respectively

Question 3

What does ESR reflect?

Answer 3

• Reflects plasma viscosity and the presence of acute phase proteins, especially fibrinogen, as well as other influences,some of which are as yet unidentified
• It can be influenced by other constituents of the blood, such as immunoglobulins, as well. The ESR can also be affected by changes that may be unrelated to inflammation, including changes in erythrocyte size, shape, and number; and by other technical factors

Question 4

Role of CRP

Answer 4

• It is a pattern recognition molecule, Influence multiple stages of inflammation, andCRP has both proinflammatory and antiinflammatory actions, although the primary effect maybe anti-inflammatory
• CRP can promote the recognition and elimination of pathogensand enhance the clearance of necrotic and apoptotic cells
• A major function of CRP is its ability to bind phosphocholine, thereby permitting recognition both of foreign pathogens that display this moiety and phospholipid constituents of damaged cells
• RP can also activate the complement system and bind to phagocytic cells via Fcreceptors, suggesting that it can initiate elimination of pathogens and targeted cells byinteraction with both humoral and cellular effector systems of inflammation
• Proinflammatory effects of CRP include activation of the complement system and the inductionin monocytes of inflammatory cytokines and tissue factor and shedding of the IL-6receptor. As a result, the CRP response to tissue injury may worsen tissue damage in somesettings

Question 5

Fibrinogen and haptoglobin roles in inflammation

Answer 5

Fibrinogen and haptoglobin influence wound healing. Fibrinogen causes endothelial cell adhesion, spreading, and proliferation, which are critical to tissue repair; and haptoglobin aids in wound repair by stimulating angiogenesis

Question 6

What is ESR?

Answer 6

The rate (expressed in mm/hour) at which erythrocytes suspended in plasma fall when placed in a vertical tube, is an indirect measure of the acute phase response and of levels of APR, particularly fibrinogen

Question 7

What are markedly elevated levels of CRP associated to?

Answer 7

Infection, most often bacterial