The acute-phase reactant proteins include all of the following EXCEPT

The acute-phase reactant proteins include all of the following EXCEPT

• A. Transferrin
• B. α1-antitrypsin
• C. Haptoglobin
• D. Fibrinogen

Answer: (A)

During inflammation, the liver ramps up production of acute-phase proteins in response to cytokines like IL-6. Some proteins rise quickly and are termed positive acute-phase reactants, while others fall and are negative acute-phase reactants. The proteins that increase include α1-antitrypsin, haptoglobin, and fibrinogen. Transferrin, on the other hand, does not rise; it decreases during inflammation to limit iron availability to pathogens, making it a negative acute-phase protein. Because the question asks for proteins that are acute-phase reactants, transferrin is the exception.

During inflammation, the liver ramps up production of acute-phase proteins in response to cytokines like IL-6. Some proteins rise quickly and are termed positive acute-phase reactants, while others fall and are negative acute-phase reactants. The proteins that increase include α1-antitrypsin, haptoglobin, and fibrinogen. Transferrin, on the other hand, does not rise; it decreases during inflammation to limit iron availability to pathogens, making it a negative acute-phase protein. Because the question asks for proteins that are acute-phase reactants, transferrin is the exception.