Anticancer activities of bovine and human lactoferricin-derived peptides.

Lactoferrin (LF) is a mammalian host defense glycoprotein with diverse biological activities. Peptides derived from the cationic region of LF possess cytotoxic activity against cancer cells in vitro and in vivo. Bovine lactoferricin (LFcinB), a peptide derived from bovine LF (bLF), exhibits broad-spectrum anticancer activity, while a similar peptide derived from human LF (hLF) is not as active.

Antibacterial and cell penetrating effects of LFcin17-30, LFampin265-284, and LF chimera on enteroaggregative Escherichia coli.

Lactoferrin (LF) is a protein with antimicrobial activity, which is conferred in part by 2 regions contained in its N-terminal lobe. These regions have been used to develop the following synthetic peptides: lactoferricin17-30, lactoferrampin265-284, and LF chimera (a fusion of lactoferricin17-30 and lactoferrampin265-284). We have reported that these LF peptides have antibacterial activity against several pathogenic bacteria; however, the exact mechanism of action has not been established.

Parasiticidal effect of synthetic bovine lactoferrin peptides on the enteric parasite Giardia intestinalis.

Giardia intestinalis is the most common infectious protozoan parasite in children. Despite the effectiveness of some drugs, the disease remains a major worldwide problem. Consequently, the search for new treatments is important for disease eradication.

Effects of lactoferrin derived peptides on simulants of biological warfare agents.

Lactoferrin (LF) is an important immune protein in neutrophils and secretory fluids of mammals. Bovine LF (bLF) harbours two antimicrobial stretches, lactoferricin and lactoferampin, situated in close proximity in the N1 domain. To mimic these antimicrobial domain parts a chimeric peptide (LFchimera) has been constructed comprising parts of both stretches (LFcin17-30 and LFampin265-284).

The Influence of Chronic Wound Extracts on Inflammatory Cytokine and Histatin Stability.

Chronic ulcers represent a major health burden in our society. Despite many available therapies, a large number of ulcers do not heal. Protein based therapies fail in part due to proteolytic activity in the chronic wound bed.

Ultrastructural effects and antibiofilm activity of LFchimera against Burkholderia pseudomallei.

Lactoferrin chimera (LFchimera), a hybrid peptide containing the two antimicrobial stretches of the innate immunity factor bovine lactoferrin, viz. LFampin265-284 and LFcin17-30, has strikingly high antimicrobial activity against the category B pathogen Burkholderia pseudomallei. The action mechanisms of LFchimera against B.

Correction: Human Salivary Micro-RNA in Patients with Parotid Salivary Gland Neoplasms.

[This corrects the article DOI: 10.1371/journal.pone.

Human Salivary Micro-RNA in Patients with Parotid Salivary Gland Neoplasms.

Background: Currently, clinical examination, ultrasound scanning (with or without fine needle aspiration cytology), preoperative CT-scan and MRI are available for the differential diagnosis of parotid gland swelling. A preliminary non-invasive salivary diagnostic tool may be helpful in the clinical decision making process. Altered salivary micro-RNA (miRNA) expression levels have been observed in saliva from patients with various cancers.

Different wound healing properties of dermis, adipose, and gingiva mesenchymal stromal cells.

Oral wounds heal faster and with better scar quality than skin wounds. Deep skin wounds where adipose tissue is exposed, have a greater risk of forming hypertrophic scars. Differences in wound healing and final scar quality might be related to differences in mesenchymal stromal cells (MSC) and their ability to respond to intrinsic (autocrine) and extrinsic signals, such as human salivary histatin, epidermal growth factor, and transforming growth factor beta1.

Histatin-1, a histidine-rich peptide in human saliva, promotes cell-substrate and cell-cell adhesion.

Histatins (Hsts) are histidine-rich peptides exclusively present in the saliva of higher primates. In this study, we explored the effects of Hsts on cell-substrate and cell-cell adhesion. Histatin (Hst)-1 caused a significant (>2-fold) increase (EC50 = 1 µM) in the ability of human adherent cells to attach and spread, even in conditions that impaired cell spreading.

Antimicrobial Peptide LL-37 Is Both a Substrate of Cathepsins S and K and a Selective Inhibitor of Cathepsin L.

Lung cysteine cathepsins B, K, L, and S contribute to physiological and pathological processes including degradation of antimicrobial peptides/proteins (AMPs) such as surfactant protein SP-A, lactoferrin, secretory leukocyte peptidase inhibitor, and beta-defensins-2 and -3. Substantial amounts of uncleaved LL-37, a 37-mer cationic AMP, were observed in the sputum of patients with cystic fibrosis (CF). Nevertheless LL-37 was degraded after prolonged incubation in CF sputum, and the hydrolysis was blocked by E-64, a selective inhibitor of cysteine proteases.

Evaluation of salivary mucins in children with deciduous and mixed dentition: comparative analysis between high and low caries-risk groups.

Objectives: The aim of this study was to examine levels of salivary mucins in children with deciduous and mixed dentition and to determine correlations between salivary mucins and dental caries status in two dentition stages.

Materials And Methods: Saliva samples were collected from preschool children with deciduous dentition aged between 4 and 6 years (n = 60) and school children with mixed dentition aged between 9 and 11 years (n = 60). In each age group, the subjects were divided into two categories: high and low caries risk (n = 30 each).

Sortase-mediated backbone cyclization of proteins and peptides.

Backbone cyclization has a profound impact on the biological activity and thermal and proteolytic stability of proteins and peptides. Chemical methods for cyclization are not always feasible, especially for large peptides or proteins. Recombinant Staphylococcus aureus sortase A shows potential as a new tool for the cyclization of both proteins and peptides.

Bactericidal effect of bovine lactoferrin and synthetic peptide lactoferrin chimera in Streptococcus pneumoniae and the decrease in luxS gene expression by lactoferrin.

Streptococcus pneumoniae (pneumococcus) is responsible for nearly one million child deaths annually. Pneumococcus causes infections such as pneumonia, otitis media, meningitis, and sepsis. The human immune system includes antibacterial peptides and proteins such as lactoferrin (LF), but its activity against pneumococcus is not fully understood.

Membrane-active mechanism of LFchimera against Burkholderia pseudomallei and Burkholderia thailandensis.

LFchimera, a construct combining two antimicrobial domains of bovine lactoferrin, lactoferrampin265-284 and lactoferricin17-30, possesses strong bactericidal activity. As yet, no experimental evidence was presented to evaluate the mechanisms of LFchimera against Burkholderia isolates. In this study we analyzed the killing activity of LFchimera on the category B pathogen Burkholderia pseudomallei in comparison to the lesser virulent Burkholderia thailandensis often used as a model for the highly virulent B.

Bovine and human lactoferricin peptides: chimeras and new cyclic analogs.

Lactoferrin (LF) is an important antimicrobial and immune regulatory protein present in neutrophils and most exocrine secretions of mammals. The antimicrobial activity of LF has been related to the presence of an antimicrobial peptide sequence, called lactoferricin (LFcin), located in the N-terminal region of the protein. The antimicrobial activity of bovine LFcin is considerably stronger than the human version.

Killing of Mycobacterium avium by lactoferricin peptides: improved activity of arginine- and D-amino-acid-containing molecules.

Mycobacterium avium causes respiratory disease in susceptible individuals, as well as disseminated infections in immunocompromised hosts, being an important cause of morbidity and mortality among these populations. Current therapies consist of a combination of antibiotics taken for at least 6 months, with no more than 60% overall clinical success. Furthermore, mycobacterial antibiotic resistance is increasing worldwide, urging the need to develop novel classes of antimicrobial drugs.

The influence of oral bacteria on epithelial cell migration in vitro.

Oral ulcerations often arise as a side effect from chemo- and radiation therapy. In a previous clinical study, Porphyromonas gingivalis was identified as a positive predictor for oral ulcerations after hematopoetic stem cell transplantation, possibly incriminating P. gingivalis in delayed healing of the ulcerations.

Discovery and prevalidation of salivary extracellular microRNA biomarkers panel for the noninvasive detection of benign and malignant parotid gland tumors.

Purpose: This study was conducted to explore the differences in salivary microRNA (miRNA) profiles between patients with malignant or benign parotid gland tumors as a potential preoperative diagnostic tool of tumors in the salivary glands.

Experimental Design: Whole saliva samples from patients with malignant (n = 38) or benign (n = 29) parotid gland tumors were obtained from the Salivary Gland Tumor Biorepository (SGTB). After total RNA isolation, human miRNA cards were used for miRNA profiling.

A heterodimer comprised of two bovine lactoferrin antimicrobial peptides exhibits powerful bactericidal activity against Burkholderia pseudomallei.

Melioidosis is a severe infectious disease that is endemic in Southeast Asia and Northern Australia. Burkholderia pseudomallei, the causative agent of this disease, has developed resistance to an increasing list of antibiotics, demanding a search for novel agents. Lactoferricin and lactoferrampin are two antimicrobial domains of lactoferrin with a broad spectrum of antimicrobial activity.

Structural diversity and mode of action on lipid membranes of three lactoferrin candidacidal peptides.

The structure and membrane interactions of three antimicrobial peptides from the lactoferrin family were investigated through different techniques. Circular dichroism shows that the peptides adopt a secondary structure in the presence of DMPC/DMPG, and DSC reveals that they all interact with these membranes, albeit differently, whereas only LFchimera has an effect in pure zwitterionic membranes of DMPC. DSC further shows that membrane action is weakest for LFcin17-30, increases for LFampin265-284 and is largest for LFchimera.

Multivalent glycopeptide dendrimers for the targeted delivery of antigens to dendritic cells.

Dendritic cells are the most powerful type of antigen presenting cells. Current immunotherapies targeting dendritic cells have shown a relative degree of success but still require further improvement. One of the most important issues to solve is the efficiency of antigen delivery to dendritic cells in order to achieve an appropriate uptake, processing, and presentation to Ag-specific T cells.

Involvement of the P2X7 purinergic receptor and c-Jun N-terminal and extracellular signal-regulated kinases in cyclooxygenase-2 and prostaglandin E2 induction by LL-37.

Periodontal disease is caused by microorganisms and host-derived inflammation involving increased cyclooxygenase-2 (COX-2) expression and prostaglandin E(2) (PGE(2)) production. We previously demonstrated that human β-defensin-3 induces COX-2 and PGE(2) in human gingival fibroblasts (HGFs). We, therefore, aimed to examine the inducible effects of LL-37, the only cathelicidin expressed in humans, on COX-2 expression and PGE(2) synthesis in HGFs and to elucidate the relevant signaling pathways.

Lactoferrin and lactoferrin chimera inhibit damage caused by enteropathogenic Escherichia coli in HEp-2 cells.

Enteropathogenic Escherichia coli (EPEC) is an important cause of infant diarrhea in developing countries. It produces a characteristic intestinal histopathological lesion on enterocytes known as 'attaching and effacing' (A/E), and these two steps are mediated by a type-III secretory system. In the present study, we evaluated the effect on the initial host cell attachment step produced by bovine lactoferrin (bLF) and three synthetic peptides: lactoferricin (LFcin), lactoferrampin (LFampin) and LFchimera.

Enhanced leishmanicidal activity of cryptopeptide chimeras from the active N1 domain of bovine lactoferrin.

Two antimicrobial cryptopeptides from the N1 domain of bovine lactoferrin, lactoferricin (LFcin17-30) and lactoferrampin (LFampin265-284), together with a hybrid version (LFchimera), were tested against the protozoan parasite Leishmania. All peptides were leishmanicidal against Leishmania donovani promastigotes, and LFchimera showed a significantly higher activity over its two composing moieties. Besides, it was the only peptide active on Leishmania pifanoi axenic amastigotes, already showing activity below 10 μM.