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PubMed2004

Production of recombinant porcine lactoferrin exhibiting antibacterial activity in methylotrophic yeast, Pichia pastoris.

Lactoferrin is a metal-binding glycoprotein exhibiting multifunctional immunoregulation of antibacterial, antioxidant, anti-endotoxin and antiviral activities. Uptake of porcine lactoferrin (PLF) has been shown to enhance resistance to diarrhea and anemia in neonatal piglets. In this study, the methylotrophic yeast, Pichia pastoris, was used to express a recombinant PLF (rPLF) gene from swine mammary gland. A synthetic secretion cassette was constructed using the inducible promoter of the alcohol oxidase-1 gene (AOX1) and the yeast alpha-mating factor signal peptide. After electroporation and Zeocin selection, several clones expressed high levels of rPLF protein which constitutes more than 30% of the total protein. A time-course study showed that rPLF mRNA transcripts are stably expressed during 120 h of culture induction. rPLF was exported into the culture supernatant at approximately 87 mg/l and a large portion of rPLF was accumulated in the cell cytoplasm at approximately 760 mg/l after 72 h of methanol induction. Recombinant PLF protein was purified via a heparin column using a fast protein liquid chromatography system. The glycosylation of P. pastoris-derived rPLF was analyzed and similar patterns to milk PLF were observed. Pepsin hydrolysate of rPLF displayed high bactericidal activity against Escherichia coli ATCC 25922 under scanning electron microscopy observation and minimal inhibitory concentration and minimal bactericidal concentration tests. Our results suggested that the methylotrophic yeast-inducible system is suitable for large-scale production of active antibacterial rPLF glycoprotein.

Animals↗
PubMed1982

Salivary secretion in chronic pancreatitis with special reference to albumin and lactoferrin.

Saliva from one parotid gland was collected under citric acid stimulation in three groups consisting of 69 control subjects and two groups consisting of 25 patients with chronic and relapsing chronic pancreatitis. Mixed saliva was collected under mechanical stimulation from 10 patients and 6 control subjects. Flow rates and the contents of bicarbonate, amylase and protein were determined. In a subgroup of patients and controls albumin and lactoferrin were measured. Wide inter- and intraindividual variations of secretory values were observed and normal values (which are reported in detail) were highly dependent from conditions of stimulation. Secretory patterns were not significantly different between patients and control subjects. It is concluded that the alterations leading to an elevation of albumin and lactoferrin and a fall in other secretory values are restricted to the exocrine pancreas and do not affect salivary glands in chronic pancreatitis.

Adult↗
PubMed1987

Diminished release of lactoferrin from polymorphonuclear leukocytes of human neonates.

In neonatal and adult polymorphonuclear leukocytes (PMN) we determined the content and the release of beta-glucuronidase, myeloperoxidase, lysozyme and lactoferrin. We found an equal total content of these proteins in adult and neonatal PMN, except for a lower lysozyme concentration in neonatal PMN. In the presence of opsonized zymosan myeloperoxidase, lysozyme and beta-glucuronidase were released in equal amounts; lactoferrin, however, was released to a lower rate from neonatal than from adult PMN (p less than 0.0005).

Adult↗
PubMed1985

Relative value of oestrogen receptor assay, lactoferrin content, and glucose-6-phosphate dehydrogenase activity as prognostic indicators in primary breast cancer.

Oestrogen receptor content, lactoferrin, hexokinase, and glucose-6-phosphate dehydrogenase levels were measured in cytosol from 25 primary breast cancers and 3 fibroadenomas. Both hexokinase and glucose-6-phosphate dehydrogenase activity were higher in malignant tissue as compared to benign breast lesions. Oestrogen receptor concentration and lactoferrin content failed to predict the development of metastatic disease, while glucose-6-phosphate dehydrogenase activity was significantly higher in cytosol from those tumours which subsequently metastasized compared to those which remained localized.

Adenofibroma↗
PubMed1991

Pseudomonas and neutrophil products modify transferrin and lactoferrin to create conditions that favor hydroxyl radical formation.

In vivo most extracellular iron is bound to transferrin or lactoferrin in such a way as to be unable to catalyze the formation of hydroxyl radical from superoxide (.O2-) and hydrogen peroxide (H2O2). At sites of Pseudomonas aeruginosa infection bacterial and neutrophil products could possibly modify transferrin and/or lactoferrin forming catalytic iron complexes. To examine this possibility, diferrictransferrin and diferriclactoferrin which had been incubated with pseudomonas elastase, pseudomonas alkaline protease, human neutrophil elastase, trypsin, or the myeloperoxidase product HOCl were added to a hypoxanthine/xanthine oxidase .O2-/H2O2 generating system. Hydroxyl radical formation was only detected with pseudomonas elastase treated diferrictransferrin and, to a much lesser extent, diferriclactoferrin. This effect was enhanced by the combination of pseudomonas elastase with other proteases, most prominently neutrophil elastase. Addition of pseudomonas elastase-treated diferrictransferrin to stimulated neutrophils also resulted in hydroxyl radical generation. Incubation of pseudomonas elastase with transferrin which had been selectively iron loaded at either the NH2- or COOH-terminal binding site yielded iron chelates with similar efficacy for hydroxyl radical catalysis. Pseudomonas elastase and HOCl treatment also decreased the ability of apotransferrin to inhibit hydroxyl radical formation by a Fe-NTA supplemented hypoxanthine/xanthine oxidase system. However, apotransferrin could be protected from the effects of HOCl if bicarbonate anion was present during the incubation. Apolactoferrin inhibition of hydroxyl radical generation was unaffected by any of the four proteases or HOCl. Alteration of transferrin by enzymes and oxidants present at sites of pseudomonas and other bacterial infections may increase the potential for local hydroxyl radical generation thereby contributing to tissue injury.

Apoproteins↗
PubMedDate not supplied

Apoptotic death of Listeria monocytogenes-infected human macrophages induced by lactoferricin B, a bovine lactoferrin-derived peptide.

Listeria monocytogenes, an intracellular facultative food-borne pathogen, was reported to induce apoptosis in vitro and in vivo in a variety of cell types with the exception of murine macrophages. These cells represent the predominant compartment of bacterial multiplication and die as a result of necrosis. In this study we showed that human non-activated and IFN-gamma-activated macrophagic-like (THP-1) cells infected with L. monocytogenes, mainly die by necrosis rather than by an apoptotic process. Two natural products derived from bovine milk, lactoferrin and its derivative peptide lactoferricin B, are capable of regulating the fate of infected human macrophages. Bovine lactoferrin treatment of macrophages protects them from L. monocytogenes-induced death whereas lactoferricin B, its derivative peptide, determines a shifting of the equilibrium from necrosis to apoptosis.

Animals↗
PubMedDate not supplied

The lactoferrin tear test in the diagnosis of Sjögren's syndrome.

PURPOSE: To assess the sensitivity and specificity of the lactoferrin tear test (LTT) in the diagnosis of keratoconjunctivitis sicca due to Sjögren's syndrome (SS), comparing it with the other lacrimal tests and with immunological tests. METHODS: 25 patients suffering from SS (24 women and 1 man, median age 51.5 years, s.d. 16.3); control group: 20 patients with various kinds of conjunctivitis without dry eye. Tests in both groups: Schirmer I (ST), BUT, ferning test, lactoferrin immunoassay, fluorescein and Rose Bengal staining. Immunological tests: serum titers of anti-nuclear (ANA), anti-DNA, anti-ENA (SS-A, SS-B, RNP, FR) antibodies. In the patients with SS, labial salivary gland biopsy was also performed. RESULTS: LTT had a specificity of 95% and a sensitivity of 72%, compared to 85% and 64% for the Schirmer I test. The ferning test has the highest sensitivity (92%), and none of the cases positive to BUT was negative to the ferning test. The combination of LTT and ferning test gave a value of 78% compared to 70% with ST. The correlations between positive LTT and positive ANA, SS-A and labial biopsy were respectively 83%, 67% and 80%, as against 67%, 50% and 65% for the Schirmer I test. CONCLUSIONS: In our study, LTT showed very high specificity, good sensitivity particularly when combined with qualitative tear tests, and a good correlation with the immunological and bioptic tests for SS. Since it is easy to perform, in our opinion LTT can be included in the diagnostic routine for keratoconjunctivitis sicca in SS.

Antibodies, Antinuclear↗
PubMed1992

Expression of alpha-lactalbumin, alpha-S1-casein, and lactoferrin genes is heterogeneous in sheep and cattle mammary tissue.

We used 35S-labeled cRNA probes to localize the sites of alpha-lactalbumin, alpha-S1-casein, and lactoferrin mRNA synthesis in sheep and forcibly weaned cattle mammary tissue. Expression of alpha-lactalbumin was absent in three of four "virgin" glands studied, present in some alveoli of "pregnant" glands but not in others, despite a similar histological appearance. In the early lactating gland, expression was high in those alveoli with few fat globules in their cells and lumen and was absent in alveoli with abundant fat globules. These observations suggest either that alpha-lactalbumin gene expression is linked to the long-term secretory activity of cells and falls once cells are resting or regressing, or that there are cyclical variations in expression, or that in the lactating gland some groups of epithelial cells are synthesizing alpha-lactalbumin and some are synthesizing fat. Expression patterns of alpha-S1-casein were similar to those of alpha-lactalbumin. Lactoferrin, in contrast, was expressed almost exclusively in the "fatty alveoli" of both species. Our results show that dramatic variations in milk gene expression can occur throughout the mammary gland of sheep and cattle and that at no stage of pregnancy, lactation, or involution can the gland be considered metabolically homogeneous.

Animals↗
PubMed2001

Lactoferrin and free secretory component of human milk inhibit the adhesion of enteropathogenic Escherichia coli to HeLa cells.

BACKGROUND: Diarrhoea caused by Escherichia coli is an important cause of infant morbidity and mortality in developing countries. Enteropathogenic Escherichia coli (EPEC) is considered one of the major causes of diarrhoea in children living in developing countries. The ability of diarrhoeagenic strains of E. coli to adhere to and colonize the intestine is the first step towards developing the disease. EPEC strains adhere to enterocytes and HeLa cells in a characteristic pattern known as localized adherence. Many epidemiological studies of diarrhoea have shown that breast-feeding protects infants from intestinal infections. Both immunoglobulin and non-immunoglobulin elements of human milk are thought to contribute to the protection from diarrhoeal agents. RESULTS: The effects of human milk and its protein components on the localized adherence of EPEC were investigated. Non-immunoglobulin components of human milk responsible for the inhibition of EPEC adhesion to HeLa cells were isolated by chromatographic fractionation of human whey proteins. Besides secretory immunoglobulin A, which has been previously reported to affect the adhesion of EPEC, free secretory component (fSC) and lactoferrin (Lf) were isolated. Even in concentrations lower than those usually found in whole milk, fSC and Lf were able to inhibit the adhesion of EPEC. alpha-lactalbumin was also isolated, but showed no activity on EPEC adhesion. CONCLUSIONS: This study demonstrated that the immunoglobulin fraction, the free secretory component and lactoferrin of human milk inhibit EPEC adhesion to HeLa cells. These results indicate that fSC and Lf may be important non-specific defence factors against EPEC infections.

Bacterial Adhesion↗
PubMed1999

Lactoferrin inhibits Bacillus cereus growth and heme analogs recover its growth.

The growth of Bacillus cereus was markedly inhibited by the addition of lactoferrin and was recovered by the addition of FeCl3. The growth inhibition was also reversed by the addition of erythrocytes and hemoglobin. B. cereus can use heme or heme-protein complex (hemoglobin-haptoglobin and hematin-albumin complexes) as iron sources in iron deficient conditions. Therefore, B. cereus uses these heme or heme-protein complexes to prevent the growth inhibition of lactoferrin in vivo.

Bacillus cereus↗
PubMed2005

Pepsin-digested bovine lactoferrin induces apoptotic cell death with JNK/SAPK activation in oral cancer cells.

Lactoferrin, a member of the transferrin family, is iron-binding and a strongly cationic 76 kDa glycoprotein. In breast milk it is secreted in high concentrations from glandular epithelia and is also present in other exocrine fluids including saliva. In the present study, we examined the biological mechanisms of apoptosis induced by pepsin-digested-lactoferrin peptide (Lfn-p) in the human oral squamous cell carcinoma cell line SAS. We found that treatment with Lfn-p induced cell death with apoptotic nuclear changes, preceded by the cleavage of caspase-3 and poly (ADP-ribose) polymerase (PARP) in the apoptotic cells. Treatment with Lfn-p induced phosphorylation of extracellular signal-regulated kinase (ERK1/2), a member of the MAP kinase family, at early stages of apoptosis. Another MAP kinase, c-Jun N-terminal kinase/stress-activated protein kinase (JNK/SAPK), was also phosphorylated by treatment with Lfn-p. Pretreatment of SAS cells with SP600125, a JNK/SAPK inhibitor, diminished Lfn-induced apoptosis, as assessed by determining released lactate dehydrogenase activity. On the other hand, the MEK1 inhibitors PD98059 or U0126 showed no effect on repression of cell death, but rather an increase. These results suggest that JNK/SAPK activation may play an important role in Lfn-p-induced apoptotic cell death of human oral squamous cell carcinoma cells.

Animals↗
PubMed2004

N-linked glycan structures of human lactoferrin produced by transgenic rice.

Human lactoferrin was produced in genetically engineered rice. N-linked glycan structures of recombinant human lactoferrin were determined. The oligosaccharides liberated by hydrazinolysis were labeled with 2-aminopyridine (PA). The PA-labeled glycans were purified by reverse-phase and size-fractionation HPLCs. The structures of these glycans were identified by HPLC, exoglycosidase digestion, and matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry. The glycan structures determined were ManFucXylGlcNAc(2) (3.4%), Man(2)FucGlcNAc(2) (2.1%), Man(3)FucGlcNAc(2) (2.5%), Man(3)FucXylGlcNAc(2) (42.5%), two isomers of Man(2)FucXylGlcNAc(2) (39.1%), Man(3)XylGlcNAc(2) (6.5%), and Man(2)XylGlcNAc(2) (3.9%).

Carbohydrate Conformation↗
PubMed2005

Recombinant human lactoferrin has preventive effects on lipopolysaccharide-induced preterm delivery and production of inflammatory cytokines in mice.

OBJECTIVE: The following animal studies have been conducted to investigate whether recombinant human lactoferrin (rh-LF) has the same effect as bovine lactoferrin (b-LF) in the prevention of preterm delivery. STUDY DESIGN: Female C3H/HeNCrj mice were pair-mated with male Crj:B6D2F1 mice. On day 15 of gestation, as a model of preterm delivery, a 50 microg/kg intraperitoneal injection of lipopolysaccharide (LPS) was administered twice with a 3-h interval between injections (2:00 and 5:00 PM). One hour prior to each LPS injection (1:00 and 4:00 PM), an intraperitoneal injection of saline, b-LF, or rh-LF (1 mg/body) was administered. In non-LPS-treated controls, an intraperitoneal injection of saline was administered 4 times (1:00, 2:00, 4:00 and 5:00 PM). Body weights and delivery times were recorded. To compare plasma levels of interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-alpha) between experimental and other pregnant mice, prepared as above, were sacrificed 6 h after the second LPS injection, and then blood samples were obtained and analyzed. RESULTS: Preterm delivery occurred (16.2+/-0.4 days of gestation) in all LPS-treated mice that were not administered LF. LF significantly prolonged gestation of LPS-treated mice: b-LF+LPS, 17.8+/-0.3 days; rh-LF+LPS, 18.0+/-0.8 days (P<0.05). LF (1 mg/body) significantly suppressed plasma IL-6 in LPS-treated mice:b-LF+LPS, 1060+/-154; rh-LF+ LPSF, 244+/-59; LPS without LF, 1628+/-115 pg/mL (P<0.05). As well, LF (1 mg/body) significantly suppressed plasma TNF-alpha in LPS-treated mice: b-LF+LPS, 88+/-36; rh-LF+LPS, 37+/-30; LPS without LF, 114+/-49 pg/mL (P<0.05). CONCLUSIONS: Rh-LF may prolong gestation in LPS-induced preterm delivery in mice, by suppressing LPS-induced plasma IL-6 and TNF-alpha augmentation.

Animals↗
PubMed1975

Components of human split ejaculates. I. Spermatozoa, fructose, immunoglobulins, albumin, lactoferrin, transferrin and other plasma proteins.

The concentrations of spermatozoa, fructose, IgG, IgA, albumin lactoferrin, transferrin, secretory piece of IgA, Beta 1C/Beta 1A-globulin (C'3-component of complement), ceruloplasmin and fibrinogen were evaluated in human split ejaculates and/or in whole human seminal plasma. The concentrations of spermatozoa, IgG, IgA, albumin and transferrin decreased from the first portion of the split ejaculate to the last, indicating that these proteins originate mostly from secretions other than the seminal vesicles. By contrast, the highest amounts of fructose and lactoferrin were present in the final portion of the split ejaculates, showing their seminal vesicle origin. No secretory piece, IgM, Beta 1C/Beta 1A-globulin, ceruloplasmin of fibrinogen could be detected in human semen. An unidentified antigen was found that has a relatively high molecular weight and shows Beta 1-mobility on immunoelectrophoresis.

Animals↗
PubMed2000

Mutagenicity of bovine lactoferrin in reverse mutation test.

The mutagenicity of bovine lactoferrin, which is an iron-binding glycoprotein in milk, was evaluated by the Ames mutagenicity test. A total of 5 test strains including 3 base-pair substitution-type strains, Salmonella typhimurium TA100, TA1535 and Escherichia coli WP2uvrA, and 2 frameshift-type strains, TA98 and TA1537, were used in the test. The test was performed by both the direct method and the metabolic activation method with preincubation applied in each instance. The concentration range of the test solution was 0.16 to 5.00 mg/100 microliters (plate). Results of the test revealed that the number of revertant colonies at each concentration of the test solutions was less than 1.4 times that of the control group. In the test system used, bovine lactoferrin did not exhibit mutagenicity.

Animals↗
PubMed2005

Intraperitoneal injection of lactoferrin ameliorates severe albumin extravasation and neutrophilia in LPS-induced inflammation in neonatal rats.

Lactoferrin (LF) plays various anti-inflammatory roles in inflammation experimentally induced by lipopolysaccharides (LPS). But the effects of LF on albumin extravasation and neutrophilia have not been elucidated. We aimed to study the effects of LF on albumin extravasation, neutrophilia and/or on other symptoms in inflammation caused by LPS in rats. Human lactoferrin (hLF) was injected (10 mg/100 mL in PBS) 18 h, or 15 min prior to, or 60 min after intraperitoneal injection of LPS in 13 days old Sprague Dawley rats. Prophylactic injection of hLF significantly ameliorated albumin extravasation in ascitic fluid at 5 h and neutrophilia in the blood at 24 h after LPS injection, but the after-injection of hLF did not. Interestingly, an injection of rat anti-TNFalpha IgG 15 min prior to LPS injection did not ameliorate albumin extravasation. Prophylactic injection of hLF significantly ameliorated other symptoms like mortality, and the decrease of phagocytotic activity of peritoneal polymorpho-nuclear leukocytes (PMNL), but did not ameliorate the decrease of platelets in the plasma. These findings suggest that hLF may be available as a medical treatment prior to surgery for prophylaxis of side effects like albumin extravasation or neutrophilia.

Albumins↗
PubMed1996

Effects of oral hygiene products containing lactoperoxidase, lysozyme, and lactoferrin on the composition of whole saliva and on subjective oral symptoms in patients with xerostomia.

This study evaluates the effects of two oral hygiene products containing nonimmunoglobulin antimicrobial agents on whole saliva and on subjective oral symptoms in patients with xerostomia. Twenty patients used a lactoperoxidase-system-containing toothpaste (Biotene) combined with the use of a mouthrinse (Biotene), comprising also lysozyme and lactoferrin, for 4 weeks. Saliva samples were collected at base line, after 4 weeks' use of the products, and at the end of a 4-week washout period. Samples were analyzed for selected biochemical and microbiologic factors. The effects on subjective oral symptoms were also recorded. A 4-week daily use of toothpaste and mouthrinse relieved the symptoms of oral dryness in 16 patients. The levels of salivary hypothiocyanite, lysozyme, lactoferrin, or myeloperoxidase activity did not change, but there was a significant decrease in salivary pH (P < 0.05), total peroxidase activity (P < 0.05), and total protein content (P = 0.01). In patients with the lowest salivary flow rates (n = 5) a significant (P > or = 0.04) increase was detected in salivary hypothiocyanite concentrations. No major changes occurred in salivary microflora. The products relieved subjective oral symptoms in most xerostomic patients, but this was not necessarily related to the presence of antimicrobial agents.

Adult↗
PubMed2002

Peptides from the N-terminal end of bovine lactoferrin induce apoptosis in human leukemic (HL-60) cells.

To determine the effects of the multifunctional iron-binding glycoprotein, lactoferrin (LF) and related compounds on the growth of leukemic cells, human myeloid leukemic cells (HL-60) were exposed to bovine lactoferrin (bLF) and proteolytic hydrolysates of bLF. Pepsin hydrolysates of bLF showed a greater growth suppressive effect than tryptic hydrolysates or mature bLF. Four peptides with proliferation inhibition activity were purified from pepsin hydrolysates by ion-exchange chromatography, reverse-phase HPLC, and gel-filtration. All peptides were from the N-terminal end, in a region where lactoferricin B (Lfcin B), an antibacterial peptide, is located. Among the four peptides, peptide 1 (pep1) was found to exhibit highest activity and corresponded to residues 17 to 38 of bLF, with a molecular weight of 2753.88. The IC50 value of this peptide was 6.3 micrograms/ml. Three other peptides were less active and corresponded to sequences 1 to 16 and 45 to 48, linked by disulfide-bridge (pep2, molecular mass of 2430.13), 1 to 15 and 45 to 46 linked by disulfide bridge (pep3, molecular mass of 2017,92) and from residues 1 to 13 (pep4, molecular mass of 1558.73). Cell proliferation inhibition activity of the peptides was thought to be due to induction of apoptosis, which was evaluated by DNA ladder formation, DNA fragmentation, enhanced expression of phosphatidyl serine, and morphological changes. The IC50 values of the three peptides were confirmed using synthetic peptides and were consistent with those of purified peptides.

Amino Acid Sequence↗