Determination Of Lactoferrin Research Articles

Fecal calprotectin and lactoferrin for the prediction of inflammatory bowel disease relapse

The purpose of the study was to determine the role of fecal calprotectin and lactoferrin in the prediction of inflammatory bowel disease relapses, both in patients with ulcerative colitis (UC) and Crohn's disease (CD), in a large, long-term, follow-up study. The prospective multicenter study included CD and UC patients who had been in clinical remission for 6 months. At baseline, patients provided a single stool sample for calprotectin and lactoferrin determination. Follow-up was 12 months in patients showing no relapse and until activity flare in relapsing patients. In all, 163 patients (89 CD, 74 UC) were included. Twenty-six patients (16%) relapsed during follow-up. Calprotectin concentrations in patients who suffered a relapse were higher than in nonrelapsing patients (239 +/- 150 versus 136 +/- 158 microg/g; P < 0.001). Relapse risk was higher in patients having high (>150 microg/g) calprotectin concentrations (30% versus 7.8%; P < 0.001) or positive lactoferrin (25% versus 10%; P < 0.05). Fecal calprotectin (>150 microg/g) sensitivity and specificity to predict relapse were 69% and 69%, respectively. Corresponding values for lactoferrin were 62% and 65%, respectively. The area under the receiver operating characteristic curve to predict relapse using calprotectin determination was 0.73 (0.69 for UC and 0.77 for CD). Better results were obtained when only colonic CD disease or only relapses during the first 3 months were considered (100% sensitivity). High fecal calprotectin levels or lactoferrin positivity was associated with clinical relapse in Kaplan-Meier survival analysis, and both fecal tests were associated with relapse in the multivariate analysis. Fecal calprotectin and lactoferrin determination may be useful in predicting impending clinical relapse-especially during the following 3 months-in both CD and UC patients.

New immunosensor for Lactoferrin determination in human milk and several pharmaceutical dairy milk products recommended for the unweaned diet

Thorough research was carried out on Lactoferrin immunosensor development. Furthermore, two different competitive procedures were used for Lactoferrin determination, in which either the antigen (Lactoferrin) or the antibody (anti-Lactoferrin) was, respectively, conjugated with horseradish peroxidase enzyme using a biotinylation process. The biotinylation of Lactoferrin and the subsequently used competition procedure for the immunosensor measurement were to get ready. Three different kinds of immunosensors were implemented, in all cases using the peroxidase enzyme as marker and hydrogen peroxide as substrate, but alternatively using as transducers one of the following sensors: (i) an amperometric electrode for H 2O 2, (ii) a Clark electrode and (iii) an iodide electrode. After optimizing the “competitive” measurement procedures and the transducer, the new Lactoferrin immunosensor was used for the determination of Lactoferrin content in human milk and in different types of dried milks or other dairy products, specifically produced and sold in chemist's shops to feed unweaned children in the first few months of life.

A new tool for distinguishing of different structural forms of lactoferrin

Lactoferrin is considered a multifunctional or multi-tasking protein. It appears to play several biological roles, whereas its structure is very crucial. The aim of this work was to investigate basic electrochemical behaviour of lactoferrin by both stationary and flow electrochemical methods with respect to study of structural changes of the compound of interest. The behaviour of lactoferrin was studied by three various electrochemical methods (linear sweep, differential pulse and square wave voltammetry). Based on the results obtained, we utilized flow injection analysis with electrochemical detection for determination of lactoferrin. We found out that the most suitable FIA-ED conditions were as follows: working electrode potential of 900 mV, Britton-Robinson buffer (pH 4.5) as mobile phase, its flow rate 1 ml.min-1. The detection limit was about tens of ng per ml. Finally, we attempted to follow the changes of lactoferrin signal in the presence of chemical compounds or under the physical conditions leading to changes in its structure. As we have shown here, electrochemical analysis enables to distinguish a change of protein structure easily and rapidly.

Determination of lactoferrin in bovine milk, colostrum and infant formulas by optical biosensor analysis

An automated, rapid, sensitive and label-free biosensor-based immunoassay for lactoferrin in bovine milk utilising surface plasmon resonance (SPR) optical detection is described. Lactoferrin content is estimated from its specific interaction with an anti-bovine lactoferrin antibody immobilised on the sensor surface in a direct- binding assay format. Samples are prepared for analysis by direct dilution into buffer. Analysis conditions, including ligand immobilisation, flow-rate, contact time and regeneration have been defined and non-specific binding considerations evaluated. Performance parameters include a working range of 0–1000 ng mL −1 , a method-detection limit of 19.9 μg mL −1 in undiluted milk, overall instrument response RSD R of 3.50%, a mean inter-assay RSD R of 10.8% for milk and surface stability over ca 500 samples. The technique was applied to the measurement of lactoferrin content of consumer milks, colostrum and infant formulas, and temporal change during early bovine lactation.

Duodenal Output and Concentration of Lactoferrin in Chronic Pancreatitis: Correlation to Amylase Secretion and Duct Morphology

To evaluate the clinical value of lactoferrin determination in duodenal contents in patients with chronic pancreatitis, three different studies were performed. No significant difference in meal stimulated output or secretion pattern was found between seven patients with chronic pancreatitis and six controls. After a meal test in 88 patients suspected for pancreatitis no correlation between concentration of lactoferrin and amylase was found. No correlation was found between degree of obstruction at endoscopic retrograde pancreaticography and duodenal concentration of lactoferrin. We conclude that the diagnostic value of lactoferrin determinations in chronic pancreatitis is doubtful.