Changes in plasma fibronectin during acute nutritional deprivation in healthy human subjects.

1. Plasma fibronectin, a glycoprotein, is an opsonin of the reticuloendothelial system. 2. In ten healthy volunteers starved for 4.5 d, daily measurements showed a rapid reduction in plasma fibronectin, no alteration in either C3 or plasma transferrin and, at the end of the starvation period, an elevated serum albumin. 3. On refeeding, plasma fibronectin rapidly returned to its prestarvation level but plasma transferrin was significantly reduced and did not recover by the end of the study. 4. Changes in plasma fibronectin may be a sensitive index of nutritional status. The reduction of plasma fibronectin in short-term starvation may compromise host defence tolerance of injury and sepsis.