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PubMed1981

Growth inhibition of Staphylococcus aureus after experimental infection of the udder by high and low concentration of lactoferrin and lysozyme in milk.

Ten Holstein-Friesian cows were distributed according to their lactoferrin and lysozyme concentrations in milk into groups with high and low concentrations. In each cow, a front and a rear mammary quarter was infected by inoculation of 10(8) colony forming units of Staphylococcus aureus while the other two quarters were infused with 2 ml of sterile milk. The reaction was observed during the following nine days. After 10 hours the cell count, the lactoferrin and lysozyme concentrations were increased in the infected and control quarters. In milk samples with a high initial lactoferrin concentration the colony forming units of S. aureus were higher than in those with a low concentration. In milk samples with a high lysozyme concentration with colony forming units of S. Aureus were significantly lower than in those with low concentrations. These results show, that the lysozyme concentration in milk of healthy udders could indicate the preparedness for defense against infectious diseases.

Animals↗
PubMed1984

Monocyte and NK cell cytotoxic activity in human adherent cell preparations: discriminating effects of interferon and lactoferrin.

The comparative cytotoxic specificities of freshly isolated human adherent and nonadherent blood mononuclear cells were examined against seven established target cell lines in 4 and 18 hr chromium release assays. The relative sensitivity of each target cell line to the cytotoxic effects of both adherent and nonadherent effector cells in cultures was identical. Moreover, the relative enhancing effects of interferon on cytotoxicity by both effector cell types were also identical. These adherent cell preparations were contaminated with up to 6% NK cells, as demonstrated by OKM1 staining and flow microfluorometry. These NK cells were loosely adherent and could be removed by vigorous wash procedures. The remaining tightly adherent monocytes also had the capacity to kill K562 cells and Chang cells, but these cytotoxic effects could not be increased by interferon. Enhancement by lactoferrin, however, was consistently observed. Treatment of mononuclear cells with Leu-lla, a monoclonal antibody that reacts with all NK cells, also abolished the enhancing effects of interferon, but not lactoferrin. These studies suggest that caution must be exercised in attributing all cytotoxic activities in adherent cell preparations to monocytes, and that lactoferrin and interferon can be used as functional probes to detect two distinct blood mononuclear cell subsets with natural cytotoxicity.

Cell Adhesion↗
PubMed1983

Sequential changes in serum albumin, immunoglobulin (IgG1, IgG2, IgM) and lactoferrin concentrations in milk following infusion of Escherichia coli into the udder of immunised and unimmunised cows.

Two immunised and three unimmunised cows were infected in a single mammary gland with 10(4) CFU of the vaccine Escherichia coli strain. Immunisation comprised systemic (subcutaneous) injection of killed bacteria at drying-off and one intramammary infusion five weeks later. Immunoglobulin (Ig) G1, IgG2, lgM, serum albumin (BSA) and lactoferrin concentrations were monitored by sampling the inoculated glands at 2 h-intervals during the first 16 h post-inoculation, then at each milking for four days. Whether immunised or not, mammary glands started to react at 10 h post-inoculation. During the early acute phase, IgG1 and IgG2 permeated from blood into milk at a rate similar to BSA. Later on, IgM (and at a lower degree IgG1) concentrations were higher than expected on the basis of passive transfer. Marked protein exudation was seen in all of the cows but one. Nevertheless, this cow (immunised) showed an intense cellular reaction like the other animals. Lactoferrin concentrations rose from 24-32 h post-inoculation and remained elevated to the end of the observed period in inoculated quarters in unimmunised cows. By contrast, in immunised cows lactoferrin concentrations remained low. Heat-labile bactericidal activity against a serum-sensitive E. coli strain appeared concomitantly with rise in BSA concentration. Heat-resistant bactericidal activity of cell-free milk was detected one or two days later in three of the cows. Bacteriological cure of quarters occurred without therapy in all cases.

Animals↗
PubMed1983

[Critical study of the analysis of lactoferrin in duodenal fluid in the diagnosis of chronic pancreatitis].

In a prospective study we have measured the lactoferrin level of duodenal juice under secretin plus caerulein pancreatic stimulation in 78 subjects. Subjects was divided in 4 groups as follows: 27 controls, 11 pancreatic disease without chronic pancreatitis (CP), 17 CP and 23 suspicions of CP. Lactoferrin was assayed by radial immunodiffusion and the level was referred to lipase activity. The test was considered as positive when lactoferrin (microgram/ml) X 100/lipase (U/ml) greater than 0.1. No one control subject had a positive test, 2 pancreatic cancers out of 4, 1 acute pancreatitis out of 7, 12 CP out of 17 had a positive test. The sensitivity (0.71) and the specificity (0.92) of the test do not allow us to propose this test as unequivocal in the diagnosis of CP.

Body Fluids↗
PubMed1984

[Plasma lactoferrin and the blood count of polynuclear neutrophils].

Plasmatic lactoferrin measure (LF) by immuno-enzymatic technique combined with neutrophil blood count (PN) on 100 subjects (controls and patients) allows us to show a LF increase proportional to circulating blood neutrophils. In neutropenia, plasmatic lactoferrin measure seems able to divide the central causes from the peripheric ones. Regarding the granulocytosis, LF levels are clearly higher in myeloproliferative diseases than in other causes. Lactoferrin could therefore represent an index of total circulating neutrophil pool but also seems to reflect the granulocyte activation.

Adult↗
PubMed1984

[Diagnosis of chronic pancreatitis based on the determination of lactoferrin and calcium in the duodenal juice?].

The diagnostic relevance of measuring calcium and lactoferrin in duodenal juice collected after stimulation is unclear. Concentration and output of these compounds were therefore analyzed after maximal stimulation of the pancreas according to Ribet, the duodenal juice being collected during an endoscopic procedure as described earlier. Kinetics of secretion showed a maximum within the first 10 minutes. Values of calcium and lactoferrin were not statistically different in normal persons (n = 32) and patients with chronic pancreatitis (n = 11). There was a good correlation to concentration of bilirubin (p less than 0.001), however no correlation to concentrations of immunoreactive trypsin and lipase. It must be assumed, that calcium and lactoferrin in duodenal juice are not only of pancreatic origin. These measurements are therefore useless in the diagnosis of pancreatitis.

Adult↗
PubMed1981

Selectively aspirated pure pancreatic secretion. Viscosity, trypsin activity, protein concentration and lactoferrin content of pancreatic juice in chronic pancreatitis.

The viscosity, trypsin activity, protein concentration and lactoferrin concentration in selectively aspirated, pure pancreatic secretion uncontaminated by bile, were determined in 46 patients with chronic pancreatitis and compared with the values obtained in 39 control subjects. The viscosity was measured using a modified capillary viscosimeter, the trypsin activity and the protein concentration using photometry, and the concentration of lactoferrin employing a new standard. It was found that in chronic pancreatitis, viscosity, trypsin activity and lactoferrin concentration was also found to be increased, but the differences were not significant. The results of this examination support the hypothesis that precipitation of protein-containing material in the pancreatic ducts, delayed outflow of secretion and premature activation of trypsin are pathogenically important factors in chronic pancreatitis.

Adult↗
PubMed1995

Inhibitory effect of lactoferrin on the adhesion of Actinobacillus actinomycetemcomitans and Prevotella intermedia to fibroblasts and epithelial cells.

Adhesion of the periodontitis-associated bacteria Actinobacillus actinomycetemcomitans and Prevotella intermedia to monolayers of fibroblasts, HEp-2, KB and HeLa cells was quantified with radiolabeled bacteria. Bacterial adhesion was also examined microscopically with Giemsa-stained non-radioactive preparations. The degree of bacterial adherence was dependent on the growth phase of the bacteria. Strains at the exponential phase adhered to a greater extent than those at the stationary phase of growth. Both human and bovine lactoferrins competitively inhibited the adhesion of A. actinomycetemcomitans and P. intermedia to all tested cell monolayers. The inhibitory effect was dose-dependent in the concentration range 0.5-2500 micrograms/ml and not related to the bacterial growth phase. In the presence of lactoferrin, decreased association of bacteria with the cell monolayers was also found by microscopic examination of the preparations. The present findings indicate that lactoferrin may prevent the establishment of bacteria in periodontal tissues through adhesion-counteracting mechanisms in addition to its bacteriostatic and bactericidal properties.

Aggregatibacter actinomycetemcomitans↗
PubMed1993

[Lactoferrin in cervical mucus of patients with chorioamnionitis].

The antimicrobial activity of cervical mucus is regarded as a local defense mechanism against ascending infections by the vaginal bacterial flora. In this study, the content of lactoferrin in cervical mucus of patients with chorioamnionitis (CAM) and its correlation with other indicators of infection were determined. The results obtained are summarized as follows: 1. The lactoferrin content in cervical mucous was higher in pregnant than in non-pregnant women. It was significantly lower in CAM(+) patients than in CAM(-) patients (P < 0.001) in preterm labor and was lower in preterm labor than in full-term control (P < 0.002). Elastase contents in cervical mucus of CAM(+) patients were significantly higher than full-term control levels (P < 0.001), and showed a negative correlation with lactoferrin contents. 2. With regard to other indicators of infection, CRP, ESR, and WBC were higher in CAM(+) patients and fibronectin was detected (> 50 ng/ml) in the cervical mucus of all CAM(+) patients.

Cervix Mucus↗
PubMedDate not supplied

[Immunoenzyme method of determining human lactoferrin and its use for diagnosing purulent-septic complications].

A solid-phase enzyme immunoassay of human lactoferrin was developed, which was used in diagnosis of some septic diseases. The test system developed enabled lactoferrin to be measured in the blood serum and plasma of healthy volunteers: 955.8 +/- 74.4 and 405.5 +/- 27.7 mg/e, respectively. This assay may be used also in measurement of blood serum lactoferrin levels in various pathological states and particularly applied for detection of postnatal pyoseptic failures before their clinical manifestations.

Humans↗
PubMed1997

Lactoferrin in tears in contact lens wearers.

PURPOSE: The purpose of this study was to examine the concentration of lactoferrin in 126 healthy subjects before being fitted with contact lenses. We obtained repeat measurements 9 months following contact lens fitting in patients who developed giant papillary conjunctivitis and in those who were successful contact lens wearers. METHODS: We accomplished tear stimulation by the use of Allyl sulphide, a non-toxic organic compound. We measured lactoferrin by the radial immuno-diffusion technique. RESULTS: We found a significant decrease of lactoferrin levels in the tears of patients with giant papillary conjunctivitis.

Adolescent↗
PubMed1998

[Immunoenzyme method of lactoferrin analysis].

The authors propose a highly effective method for isolation of lactoferrin from female colostrum. Lactoferrin is measured by the sandwich enzyme immunoassay. Its concentrations in the serum, urine, amniotic and cerebrospinal fluid in health are measured. The advantages of the method for lactoferrin purification and the practical significance of this protein are discussed.

Colostrum↗
PubMed1998

Immunoregulatory effects of a nutritional preparation containing bovine lactoferrin taken orally by healthy individuals.

The aim of this study was to monitor several immune parameters in 17 healthy volunteers taking orally commercially available capsules containing bovine lactoferrin (BLFT) for 10 days (40 mg of BLFT daily). We determined leukocyte number and content of main blood cell types, spontaneous and phytohemagglutinin A (PHA)-induced proliferation of lymphocytes, plasma levels of interleukin 6 (IL-6) and tumor necrosis factor alpha (TNF-alpha) as well as spontaneous and lipopolysaccharide (LPS)-induced production of these cytokines in peripheral blood cell cultures. All measurements were performed before, one day and 14 days following cessation of BLFT treatment. We established some, transient drop in the percentage of neutrophils accompanied by an opposite phenomenon with regard to lymphocyte levels. More profound changes were registered in the percentage of other cell types, for example a 100% increase in the level of immature cell forms (bands) was noted. At the same time the percentages of eosinophils and monocytes declined significantly. All these changes were, however, more individual and regulatory, the direction of these changes depended on initial picture of blood cells. Although the proliferative response of lymphocytes showed, on average, a transient decrease, differentiated effects of BLFT treatment were observed depending on initial ability of lymphocytes to proliferate. TNF-alpha serum levels showed a tendency to decrease during the monitoring time, the changes of IL-6 levels were, however, not significant. As in the case of the proliferative response, the treatment with BLFT was regulatory with respect to serum TNF-alpha levels. When we analyzed spontaneous and LPS-induced cytokine production in cell cultures we found that mainly the mean spontaneous response was affected (inhibition). We also observed a typical, regulatory action of BLFT on the level of spontaneously produced IL-6. This kind of regulatory action of BLFT was also found in the case of spontaneously produced TNF-alpha in cell cultures. The influence of other ingredients such as selenium or vitamins, contained in the capsules, cannot be excluded, although our latest data showed that orally taken bovine lactoferrin alone can induce identical changes as BLFT. Taken together, we revealed regulatory effects of oral treatment with commercially available capsules, containing BLFT. The results indicate that oral administration on BLFT-containing capsules may regulate some immune parameters in healthy individuals. In addition, the data suggest that bovine lactoferrin may be applied in clinic to improve the immune status of patients.

Adjuvants, Immunologic↗
PubMed1994

Structure of copper- and oxalate-substituted human lactoferrin at 2.0 A resolution.

The three-dimensional structure of human dicupric monooxalate lactoferrin, Cu(2)oxLf, has been determined to 2.0 A resolution, using X-ray diffraction data collected by diffractometry to 2.5 A resolution, and oscillation photography on a synchrotron source to 2.0 A resolution. Difference electron-density maps calculated between Cu(2)oxLf and both dicupric lactoferrin, Cu(2)Lf, and diferric lactoferrin, Fe(2)Lf, showed that the oxalate had replaced a carbonate in the C-terminal binding site, and that, relative to Cu(2)Lf, there were no significant differences in the N-terminal site. The structure was then refined crystallographically by restrained least-squares methods. The final model, in which the r.m.s. deviation in bond distances is 0.017 A, contains 5314 protein atoms (691 residues), two Cu(2+) ions, one bicarbonate ion, one oxalate ion, 325 solvent molecules and one sugar residue. The crystallographic R factor of 0.193 is for 46 134 reflections in the range 8.0 to 2.0 A resolution. The oxalate ion is coordinated to copper in a 1,2-bidentate fashion, and the added bulk of the anion results in the rearrangement of the side chains of nearby arginine and tyrosine residues. No other major alterations in the molecule can be observed, the overall protein structure being the same as that for Cu(2)Lf and Fe(2)Lf.

Journal Article↗
PubMed1972

Association of lactoferrin with lysozyme in granules of human polymorphonuclear leukocytes.

Lactoferrin is contained in cytoplasmic granules of human polymorphonuclear leukocytes. Upon centrifugation, it sediments in a band of granules that also contain 50% of the lysozyme activity. This granule class is distinct from others associated with alkaline phosphatase and peroxidase. The granules are latent for lactoferrin as only lysed granules have the capacity specifically to inhibit antigen binding by anti-lactoferrin serum.

Animals↗
PubMedDate not supplied

Involvement of bovine lactoferrin moieties in the inhibition of herpes simplex virus type 1 infection.

Bovine lactoferrin (BLf) is an iron binding protein folded in two lobes, N- and C-lobes. In this study we have reported the inhibitory activity towards herpes simplex virus type 1 (HSV-1) in vitro infection of BLf tryptic digested N- and C-lobes in comparison with the whole protein. The N-lobe and C-lobe exerted an anti-herpesvirus activity 50- and 10-fold lower than native BLf, respectively. In order to assess the phase of viral replication affected, lactoferrin-derived lobes were added to the cells at different non cytotoxic concentrations, during the whole cycle of viral infection or during viral attachment step, demonstrating that both lobes interfered with the early phases of infection. Among the BLf tryptic digested fragments, two negatively-charged small peptides deriving from N-lobe, previously shown effective towards HSV-1, have been further studied. We assessed that the net negative charge of these peptides was not responsible for the antiviral activity since their activity was not modified when the aspartic and glutamic acidic residues of these peptides were replaced with asparagine and glutamine, respectively. The experiments here reported confirm a pivotal role of N-lobe in inhibiting viral infection. However, the residual inhibiting activity of C-lobe and the similar efficacy shown by negatively or positively charged peptides strongly support the idea that the antiviral activity of bovine lactoferrin cannot be fully explained simply on the basis of competition between the protein and viral recognition sites for binding to glycosaminoglycans.

Journal Article↗
PubMed2001

Assessment of plasma lactoferrin in Parkinson's disease.

Iron may play an important role in the pathogenesis of Parkinson's disease (PD). Recent studies have shown that the iron-transporting glycoprotein lactoferrin (LF) and its receptor are increased in the substantia nigra (SN) in PD. We investigated whether plasma levels of LF are altered in dopa-responsive PD. Plasma LF was not different between patients with PD (n = 23; 306 +/- 116 [mean +/- standard deviation] ng/ml) and age- and sex-matched healthy control subjects (n = 15; 359 +/- 126 ng/ml ). However, LF was inversely correlated with PD severity (r = -0.68, P = 0.002), an association that remained significant after adjustment for treatment with levodopa, monoaminooxidase inhibitors, and dopa agonists (r = -0.53, P = 0.017). Plasma transferrin and ferritin levels were not different between groups and neither correlated with disease severity nor with LF levels. Together with the result of increased nigral lactoferrin, this finding is compatible with the hypothesis of an imbalance between LF levels in blood and SN in progressing PD. Larger and particularly longitudinal studies and measurements of LF in cerebrospinal fluid are warranted to further examine the role of LF in PD.

Dopamine↗
PubMed2005

Expression and prognostic value of lactoferrin mRNA isoforms in human breast cancer.

We investigated the expression levels of human lactoferrin (Lf), a steroid hormone-inducible gene product the expression of which is often altered during oncogenesis, and of Delta-lactoferrin (DeltaLf), its alternative isoform, which has been shown to be absent from tumor cell lines in commonly used human breast epithelial cell lines, using semiquantitative RT-PCR. Both mRNAs were detected but with levels of expression lower than those found in normal breast epithelial cells. This downregulation was much more visible for DeltaLf since its expression was either significantly diminished (BT-20, MCF-7 cell lines) or practically absent (MDA-MB-231, T-47D, HBL 100 cell lines). In order to determine whether Lf gene products are useful prognosic tools, we further analyzed their expression levels in 99 primary breast cancer biopsies. DeltaLf transcripts were found in all of the samples, whereas Lf transcripts were found in 88% of them. Lf and DeltaLf expression levels were positively correlated (p = 0.003). Lf expression was related to tumor type with a higher recovery in lobular-type tumors (p = 0.04). DeltaLf expression was related to the histoprognostic grading (p = 0.02). In univariate analyses, DeltaLf and Lf expressions were prognosis parameters, high concentrations being associated with a longer overall survival.

Base Sequence↗