Search

For the determination of lactoferrin in human plasma we describe a double-sandwich immunoenzymatic assay in 3 steps using tubes as the solid phase. The analytical performances are acceptable. Within-run and between-run CVs are respectively 4% and 13%, the lower limit of detection is 8 micrograms/l. Sensitivity and specificity are good. The influence on lactoferrin concentration of time elapsing from blood sampling to separation of plasma from cells was studied in order to define the optimal conditions of storage and centrifugation. The range of concentration obtained on 22 healthy adults lies between 59 and 345 micrograms/l.

Lactoferrin and transferrin exhibit very similar structure and biochemical properties but they behave as two distinct antigens and their affinity for ferric ions is not of the same magnitude. The biological functions of lactoferrin are not all well understood. It has strong bacteriostatic properties, it plays a role as a regulator of human granulopoiesis and it is probably involved in the hyposideremia of acute inflammation. Measurement of lactoferrin was first applied in pancreatic juice or duodenal fluid as a diagnostic tool for pancreatic diseases. More recently plasma lactoferrin has been used as an index of total circulating neutrophil pool in hematological disorders and in uremic patients during hemodialysis. Its clinical usefulness is still discussed for the early diagnostic of infectious diseases.