ABSTRACT
α1-Acid glycoprotein (α1-AGP) was isolated in pure form 40 years ago,1 and extensive research on its biochemistry performed in the 1960s and 1970s led to the determination of its complete amino acid sequence as well as its carbohydrate composition. In the rat, an increase in the α1-AGP plasma concentrations is correlated with an increase in hepatic mRNA, a finding that confirms earlier observations on other acute phase proteins. Plasma α1-AGP concentrations are elevated in obesity, old age, malnutrition, and chronic renal failure. Interaction of α1-AGP with the lymphoid cell surface has been demonstrated, and it has been hypothesized that α1-AGP acts as a nonspecific immunosuppressive agent which, during the acute phase response, may contribute to limiting, modulating, or directing the host immune response. A good overview of the possible physiological functions of α1-AGP should refer to studies that try to find an homology between α1-AGP and other proteins.
