Lactoferrin and host defense

Evaluation of immunogenicity of enterobactin conjugate vaccine for the control of Escherichia coli mastitis in dairy cows

Mastitis is the most common disease of dairy cows that incurs severe economic losses to the dairy industry. Currently, environmental mastitis pathogens are a major problem for most dairy farms. A current commercially available Escherichia coli vaccine does not prevent clinical mastitis and production losses, likely due to antibody accessibility and antigenic variation issues. Therefore, a novel vaccine that prevents clinical disease and production losses is critically needed. Recently a nutritional immunity approach, which restricts bacterial iron uptake by immunologically sequestering conserved iron-binding enterobactin (Ent), has been developed. The objective of this study was to evaluate the immunogenicity of the keyhole limpet hemocyanin-enterobactin (KLH-Ent) conjugate vaccine in dairy cows. Twelve pregnant Holstein dairy cows in their first through third lactations were randomized to the control or vaccine group, with 6 cows per group. The vaccine group received 3 subcutaneous vaccinations of KLH-Ent with adjuvants at drying off (D0), 20 (D21), and 40 (D42) days after drying off. The control group was injected with phosphate-buffered saline (pH 7.4) mixed with the same adjuvants at the same time points. Vaccination effects were assessed over the study period until the end of the first month of lactation. The KLH-Ent vaccine did not cause any systemic adverse reactions or reduction in milk production. Compared with the control group, the vaccine elicited significantly higher levels of serum Ent-specific IgG at calving (C0) and 30 d postcalving (C30), mainly its IgG2 fraction, which was significantly higher at D42, C0, C14, and C30 d, with no significant change in IgG1 levels. Milk Ent-specific IgG and IgG2 levels in the vaccine group were significantly higher on C30. Fecal microbial community structures were similar for both control and vaccine groups on the same day and shifted directionally along the sampling days. In conclusion, the KLH-Ent vaccine successfully triggered strong Ent-specific immune responses in dairy cows without significantly affecting the gut microbiota diversity and health. The results show that Ent conjugate vaccine is a promising nutritional immunity approach in control of E. coli mastitis in dairy cows.

The immunomodulatory effects of lactoferrin and its derived peptides on NF-κB signaling pathway: A systematic review and meta-analysis

BACKGROUND

Lactoferrin is a versatile protein with important modulatory functions in inflammation and immune response. This glycoprotein can bind and sequester iron and LPS, thereby intervening in certain signaling pathways and biological processes. In the present meta-analysis, we aimed to pool experimental data regarding the immunomodulatory effects of lactoferrin and its derived peptides on the NF-κB signaling pathway.

MATERIALS

We searched PubMed, Google Scholar, and Web of Science databases and obtained all related articles published before April 2022. Finally, 25 eligible studies were selected, and their reports were analyzed.

METHODS

We used Review Manager Version 5.2 to compute the standardized mean difference (SMD) and its 95% confidence interval. In addition, the source of heterogeneity was explored using meta-regression and sensitivity analysis. The symmetry of the funnel plot and Egger's test were also used to evaluate publication bias utilizing Comprehensive Meta-Analysis Version 2.

RESULTS

Comparing the group of cells and animals exposed to lipopolysaccharide alone with the group that received pretreatment with lactoferrin and its derivatives, we observed significant reductions in TNF-α, IL-1 beta, and IL-6 levels by 8.73 pg/mL, 2.21 pg/mL, and 3.24 pg/mL, respectively, in the second group. Additionally, IKK-β, p-IκB, and NF-κB (p65) levels were significantly lower by 7.37-fold, 15.02-fold, and 3.88-fold, respectively, in various cells and tissues.

CONCLUSION

Based on the results of this meta-analysis, lactoferrin and its derived peptides can be considered potent prophylactic and therapeutic candidates against inflammation-associated diseases by targeting the NF-kB pathway.

Further Insights into the Gut Microbiota of Cow's Milk Allergic Infants: Analysis of Microbial Functionality and Its Correlation with Three Fecal Biomarkers

Cow's milk allergy (CMA) is one of the most prevalent food allergies in children. Several studies have demonstrated that gut microbiota influences the acquisition of oral tolerance to food antigens at initial stages of life. Changes in the gut microbiota composition and/or functionality (i.e., dysbiosis) have been linked to inadequate immune system regulation and the emergence of pathologies. Moreover, omic sciences have become an essential tool for the analysis of the gut microbiota. On the other hand, the use of fecal biomarkers for the diagnosis of CMA has recently been reviewed, with fecal calprotectin, α-1 antitrypsin, and lactoferrin being the most relevant. This study aimed at evaluating functional changes in the gut microbiota in the feces of cow's milk allergic infants (AI) compared to control infants (CI) by metagenomic shotgun sequencing and at correlating these findings with the levels of fecal biomarkers (α-1 antitrypsin, lactoferrin, and calprotectin) by an integrative approach. We have observed differences between AI and CI groups in terms of fecal protein levels and metagenomic analysis. Our findings suggest that AI have altered glycerophospholipid metabolism as well as higher levels of lactoferrin and calprotectin that could be explained by their allergic status.

Flexor Tendon Adhesion Formation: Current Concepts

Over the years, various physical and chemical/biological methods of inhibiting adhesion formation have been developed, focusing on how to suppress healing around the tendon and not inhibit healing within the tendon. Unfortunately, however, these methods are accompanied by drawbacks, both large and small, and no absolute antiadhesion method capable of maintaining tendon repair strength has yet been developed. Recent innovations in biomaterials science and tissue engineering have produced new antiadhesion technologies, such as barriers combined with cytokines and cells, which have improved outcomes in animal models, and which may find clinical relevance in the future.

Lactoferrin, Osteopontin and Lactoferrin–Osteopontin Complex: A Critical Look on Their Role in Perinatal Period and Cardiometabolic Disorders

Milk-derived bioactive proteins have increasingly gained attention and consideration throughout the world due to their high-quality amino acids and multiple health-promoting attributes. Apparently, being at the forefront of functional foods, these bioactive proteins are also suggested as potential alternatives for the management of various complex diseases. In this review, we will focus on lactoferrin (LF) and osteopontin (OPN), two multifunctional dairy proteins, as well as to their naturally occurring bioactive LF–OPN complex. While describing their wide variety of physiological, biochemical, and nutritional functionalities, we will emphasize their specific roles in the perinatal period. Afterwards, we will evaluate their ability to control oxidative stress, inflammation, gut mucosal barrier, and intestinal microbiota in link with cardiometabolic disorders (CMD) (obesity, insulin resistance, dyslipidemia, and hypertension) and associated complications (diabetes and atherosclerosis). This review will not only attempt to highlight the mechanisms of action, but it will critically discuss the potential therapeutic applications of the underlined bioactive proteins in CMD.

Mastitis: Impact of Dry Period, Pathogens, and Immune Responses on Etiopathogenesis of Disease and its Association with Periparturient Diseases

Mastitis is an inflammation of the mammary gland initiated by pathogenic bacteria. In fact, mastitis is the second most important reason for the culling of cows from dairy herds, after infertility. In this review we focus on various forms of mastitis, including subclinical and clinical mastitis. We also stress the importance of the dry-off period as an important time when pathogenic bacteria might start their insult to the mammary gland. An important part of the review is the negative effects of mastitis on milk production and composition, as well as economic consequences for dairy farms. The two most important groups of bacteria that are involved in infection of the udder, Gram-negative and Gram-positive bacteria, are also discussed. Although all cows have both innate and adaptive immunity against most pathogens, some are more susceptible to the disease than others. That is why we summarize the most important components of innate and adaptive immunity so that the reader understands the specific immune responses of the udder to pathogenic bacteria. One of the most important sections of this review is interrelationship of mastitis with other diseases, especially retained placenta, metritis and endometritis, ketosis, and laminitis. Is mastitis the cause or the consequence of this disease? Finally, the review concludes with treatment and preventive approaches to mastitis.

Lactoferrin Ameliorates Ovalbumin-Induced Asthma in Mice through Reducing Dendritic-Cell-Derived Th2 Cell Responses

Asthma is a chronic respiratory disease with symptoms such as expiratory airflow narrowing and airway hyperresponsiveness (AHR). Millions of people suffer from asthma and are at risk of life-threatening conditions. Lactoferrin (LF) is a glycoprotein with multiple physiological functions, including antioxidant, anti-inflammatory, antimicrobial, and antitumoral activities. LF has been shown to function in immunoregulatory activities in ovalbumin (OVA)-induced delayed type hypersensitivity (DTH) in mice. Hence, the purpose of this study was to investigate the roles of LF in AHR and the functions of dendritic cells (DCs) and Th2-related responses in asthma. Twenty 8-week-old male BALB/c mice were divided into normal control (NC), ovalbumin (OVA)-sensitized, and OVA-sensitized with low dose of LF (100 mg/kg) or high dose of LF (300 mg/kg) treatment groups. The mice were challenged by intranasal instillation with 5% OVA on the 21st to 27th day after the start of the sensitization period. The AHR, cytokines in bronchoalveolar lavage fluid, and pulmonary histology of each mouse were measured. Serum OVA-specific IgE and IgG1 and OVA-specific splenocyte responses were further detected. The results showed that LF exhibited protective effects in ameliorating AHR, as well as lung inflammation and damage, in reducing the expression of Th2 cytokines and the secretion of allergen-specific antibodies, in influencing the functions of DCs, and in decreasing the level of Th2 immune responses in a BALB/c mouse model of OVA-induced allergic asthma. Importantly, we demonstrated that LF has practical application in reducing DC-induced Th2 cell responses in asthma. In conclusion, LF exhibits anti-inflammation and immunoregulation activities in OVA-induced allergic asthma. These results suggest that LF may act as a supplement to prevent asthma-induced lung injury and provide an additional agent for reducing asthma severity.

Identification of novel alternative splicing associated with mastitis disease in Holstein dairy cows using large gap read mapping

Background

Mastitis is a very common disease in the dairy industry that producers encounter daily. Transcriptomics, using RNA-Sequencing (RNA - Seq) technology, can be used to study the functional aspect of mastitis resistance to identify animals that have a better immune response to mastitis. When the cow has mastitis, not only genes but also specific mRNA isoforms generated via alternative splicing (AS) could be differentially expressed (DE), leading to the phenotypic variation observed. Therefore, the objective of this study was to use large gap read mapping to identify mRNA isoforms DE between healthy and mastitic milk somatic cell samples (N = 12). These mRNA isoforms were then categorized based on being 1) annotated mRNA isoforms for gene name and length, 2) annotated mRNA isoforms with different transcript length and 3) novel mRNA isoforms of non - annotated genes.

Results

Analysis identified 333 DE transcripts (with at least 2 mRNA isoforms annotated, with at least one being DE) between healthy and mastitic samples corresponding to 303 unique genes. Of these 333 DE transcripts between healthy and mastitic samples, 68 mRNA isoforms are annotated in the bovine genome reference (ARS.UCD.1.2), 249 mRNA isoforms had novel transcript lengths of known genes and 16 were novel transcript lengths of non - annotated genes in the bovine genome reference (ARS.UCD.1.2). Functional analysis including gene ontology, gene network and metabolic pathway analysis was performed on the list of 288 annotated and unique DE mRNA isoforms. In total, 67 significant metabolic pathways were identified including positive regulation of cytokine secretion and immune response. Additionally, numerous DE novel mRNA isoforms showed potential involvement with the immune system or mastitis. Lastly, QTL annotation analysis was performed on coding regions of the DE mRNA isoforms, identifying overlapping QTLs associated with clinical mastitis and somatic cell score.

Conclusion

This study identified novel mRNA isoforms generated via AS that could lead to differences in the immune response of Holstein dairy cows and be potentially implemented in future breeding programs.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12864-022-08430-x.

The Role of Nutrients in Prevention, Treatment and Post-Coronavirus Disease-2019 (COVID-19)

SARS-CoV-2 virus, infecting human cells via its spike protein, causes Coronavirus disease 2019 (COVID-19). COVID-19 is characterized by shortness of breath, fever, and pneumonia and is sometimes fatal. Unfortunately, to date, there is still no definite therapy to treat COVID-19. Therefore, the World Health Organization (WHO) approved only supportive care. During the COVID-19 pandemic, the need to maintain a correct intake of nutrients to support very weakened patients in overcoming disease arose. The literature available on nutrient intake for COVID-19 is mainly focused on prevention. However, the safe intake of micro- and/or macro-nutrients can be useful either for preventing infection and supporting the immune response during COVID-19, as well as in the post-acute phase, i.e., “long COVID”, that is sometimes characterized by the onset of various long lasting and disabling symptoms. The aim of this review is to focus on the role of nutrient intake during all the different phases of the disease, including prevention, the acute phase, and finally long COVID.

Kinetic and thermodynamic of lactoferrin - Ethoxylated-nonionic surfactants supramolecular complex formation

Understanding nonionic surfactant-protein interactions is fundamental from both technological and scientific points of view. However, there is a complete absence of kinetic data for such interactions. We employed surface plasmon resonance (SPR) to determine the kinetic and thermodynamic parameters of bovine lactoferrin-Brij58 interactions at various temperatures under physiological conditions (pH 7.4). The adsorption process was accelerated with increasing temperature, while the desorption rate decreased, resulting in a more thermodynamically stable complex. The kinetic energetic parameters obtained for the formation of the activated complex, [bLF-Brij58]^‡, indicated that the potential energy barrier for [bLF-Brij58]^‡ formation arises primarily from the reduction in system entropy. [bLF-Brij58]^○ formation was entropically driven, indicating that hydrophobic interactions play a fundamental role in bLF interactions with Brij58.

The effects of orally administered lactoferrin in the prevention and management of viral infections: A systematic review

It has been demonstrated that lactoferrin (LF) plays a role in host defence, but evidence on its potential antiviral property from clinical studies is fragmented. Our systematic review aimed at identifying the effects of orally administered LF against virus infections. The systematic search was conducted on PubMed, Scopus, Web of Science, BioRxiv.org and ClinicalTrials.gov from database inception to 7th January 2021. Eligible articles investigated any virus family and provided data on the effects of orally administered LF of any origin in the prevention and/or management of confirmed viral infections in people of any age. A narrative synthesis of the results was performed. Quality was assessed with the Cochrane Risk‐Of‐Bias and ROBINS‐1 tools. A total of 27 records were included, nine of which were registered protocols. We found data on Flaviviridae (n = 10), Retroviridae (n = 3), Coronaviridae (n = 2), Reoviridae (n = 2) and Caliciviridae (n = 1). Most published trials were at high risk of bias. The findings were heterogeneous across and within viral families regarding virological, immunological and biological response, with no clear conclusion. Some weak but positive results were reported about decrease of symptom severity and duration, or reduction in viral loads. Despite high tolerability, the effects of LF as oral supplement are still inconsistent, both in preventing and managing viral infections. Small sample sizes, variety in recruitment and treatment protocols, and low study quality may have contributed to such heterogeneity. Better‐designed studies are needed to further investigate its potential benefits against viral infections, including SARS‐CoV‐2.

Lactoferrin: an overview of its main functions, immunomodulatory and antimicrobial role, and clinical significance

Lactoferrin (LF), a glycoprotein found in mucosal secretions, is characterized by a wide range of functions, including immunomodulatory and anti-inflammatory activities. Moreover, several investigations confirmed that LF displays high effectiveness against multiple bacteria and viruses and may be regarded as a potential inhibitor of enveloped viruses, such as presently prevailing SARS-CoV-2. In our review, we discuss available studies about LF functions and bioavailability of different LF forms in in vitro and in vivo models. Moreover, we characterize the potential benefits and side effects of LF use; we also briefly summarize the latest clinical trials examining LF application. Finally, we point potential role of LF in inflammatory bowel disease and indicate its use as a marker for disease severity.

Iron-withdrawing anti-infectives for new host-directed therapies based on iron dependence, the Achilles' heel of antibiotic-resistant microbes

The iron dependence of antibiotic-resistant microbes represents an Achilles' heel that can be exploited broadly. The growing global problem of antibiotic resistance of microbial pathogens wherein microbes become resistant to the very antibiotics used against them during infection is linked not only to our health uses but also to agribusiness practices and the changing environment. Here we review mechanisms of microbial iron acquisition and host iron withdrawal defense, and the influence of iron withdrawal on the antimicrobial activity of antibiotics. Antibiotic-resistant microbes are unaltered in their iron requirements, but iron withdrawal from microbes enhances the activities of various antibiotics and importantly suppresses outgrowth of antibiotic-exposed resistant microbial survivors. Of the three therapeutic approaches available to exploit microbial iron susceptibility, including (1) use of gallium as a non-functional iron analogue, (2) Trojan horse conjugates of microbial siderophores carrying antibiotics, and (3) new generation iron chelators, purposely designed as anti-microbials, the latter offers various advantages. For instance, these novel anti-microbial chelators overcome the limitations of conventional clinically-used hematological chelators which display host toxicity and are not useful antimicrobials. 3-Hydroxypyridin-4-one-containing polymeric chelators appear to have the highest potential. DIBI (developmental code name) is a well-developed lead candidate, being a low molecular weight, water-soluble copolymer with enhanced iron binding characteristics, strong anti-microbial and anti-inflammatory activities, low toxicity for animals and demonstrated freedom from microbial resistance development. DIBI has been shown to enhance antibiotic efficacy for antibiotic-resistant microbes during infection, and it also prevents recovery growth and resistance development during microbe exposure to various antibiotics. Because DIBI bolsters innate iron withdrawal defenses of the infected host, it has potential to provide a host-directed anti-infective therapy.

The Biology of Lactoferrin, an Iron-Binding Protein That Can Help Defend Against Viruses and Bacteria

Lactoferrin is a nutrient classically found in mammalian milk. It binds iron and is transferred via a variety of receptors into and between cells, serum, bile, and cerebrospinal fluid. It has important immunological properties, and is both antibacterial and antiviral. In particular, there is evidence that it can bind to at least some of the receptors used by coronaviruses and thereby block their entry. Of importance are Heparan Sulfate Proteoglycans (HSPGs) and the host receptor angiotensin-converting enzyme 2 (ACE2), as based on other activities lactoferrin might prevent severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) from attaching to the host cells. Lactoferrin (and more specifically enteric-coated LF because of increased bioavailability) may consequently be of preventive and therapeutic value during the present COVID-19 pandemic.

Current Status and Challenges in Rotigotine Delivery

Rotigotine is a non-ergoline, high lipophilic dopamine agonist. It is indicated as the first-line therapy for Parkinson's disease (PD) and Restless Leg Syndrome (RLS). However, the precise mechanism of rotigotine is yet to be known. Rotigotine has similar safety and tolerability to the other oral non-ergolinic dopamine antagonists in clinical trials, which include nausea, dizziness and somnolence. Neupro® was the first marketed transdermal patch formulation having rotigotine. The transdermal delivery system is advantageous as it enables continuous administration of the drug, thus providing steady-state plasma drug concentration for 24-hours. Intranasal administration of rotigotine allows the drug to bypass the blood-brain barrier enabling it to reach the central nervous system within minutes. Rotigotine can also be formulated as an extended-release microsphere for injection. Some challenges remain in other routes of rotigotine administration such as oral, parenteral and pulmonary, whereby resolving these challenges will be beneficial to patients as they are less invasive and comfortable in terms of administration. This review compiles recent work on rotigotine delivery, challenges and its future perspective.

Functional analysis of recombinant buffalo lactoferrin and monoferric lobes and their cytotoxic effect on buffalo mammary epithelial cells

Lactoferrin (Lf) has been involved in diverse type of cellular activities and its biochemical properties are species specific. Lf is a bilobal molecule in which each lobe binds with one Fe²⁺/Fe³⁺ ion. A lot of physiological effects of Lf are regulated by its iron binding and release properties; however these properties are species-specific. To understand the iron-binding, thermal stability and cytotoxic effect of buffalo Lf (buLf) and contribution of individual N- and C-terminal lobes therein, buLf and the truncated monoferric lobes were expressed in Kluyveromyces lactis or Pichia pastoris yeast expression systems. The iron-uptake/release behavior and thermal stability of recombinant buLf was observed similar to the Lf purified from buffalo milk. Supplementation of recombinant buLf to the buffalo mammary epithelial cells (BuMEC) culture decreased their proliferation and the cell viability in a dose dependent manner. The cell growth decreased by 37% at 1.0 mg/ml Lf. C-lobe decreased the viability of BuMEC by 15% at 1 mg/ml. The C-lobe showed greater cytotoxic effect against BuMEC in comparison to N-lobe. buLf caused a reduced expression of the casein in BuMEC. At 1.0 mg/ml of buLf, CSN2 transcript level was reduced by 74% and 78% in the normal and hormone free media, respectively. The expression of IL-1β gene in BuMEC increased by 4-5 fold in the presence of 1.0 mg/ml of Lf. The effect was similar to that observed in the involutory mammary gland, suggesting the role of elevated level of Lf in remodeling of buffalo mammary tissue during involution.

Gene Expression Indicates Altered Immune Modulation and Signaling Pathway Activation in Ovarian Cancer Patients Resistant to Topotecan

Epithelial ovarian cancer (EOC) is one of the deadliest gynecological malignancies. Topotecan remains an essential tool in second-line therapy; even so, most patients develop resistance within a short period of time. We aimed to identify biomarkers of topotecan resistance by using gene expression signatures derived from patient specimens at surgery and available subsequent responses to therapy. Gene expression was collected for 1436 patients and 10,103 genes. Based on disease progression, patients were categorized as responders/nonresponders depending on their progression free survival (PFS) state at 9, 12, 15 and 18 months after surgery. For each gene, the median expression was compared between responders and nonresponders for two treatment regimens (chemotherapy including/excluding topotecan) with Mann–Whitney U test at each of the four different PFS cutoffs. Statistical significance was accepted in the case of p < 0.05 with a fold change (FC) ≥ 1.44. Four genes (EPB41L2, HLA-DQB1, LTF and SFRP1) were consistently overexpressed across multiple PFS cutoff times in initial tumor samples of patients with disease progression following topotecan treatment. A common theme linked to topotecan resistance was altered immune modulation. Genes associated with disease progression after systemic chemotherapy emphasize the role of the initial organization of the tumor microenvironment in therapy resistance. Our results uncover biomarkers with potential utility for patient stratification.

Macrophage in vitro Response on Hybrid Coatings Obtained by Matrix Assisted Pulsed Laser Evaporation

The improvement in the research area of the implant by surface functionalization when correlated with the biological response is of major interest in the biomedical field. Based on the fact that the inflammatory response is directly involved in the ultimate response of the implant within the body, it is essential to study the macrophage-material interactions. Within this context, we have investigated the composite material-macrophage cell interactions and the inflammatory response to these composites with amorphous hydroxyapatite (HA), Lactoferrin (Lf), and polyethylene glycol-polycaprolactone (PEG-PCL) copolymer. All materials are obtained by Matrix Assisted Pulsed Laser Evaporation (MAPLE) technique and characterized by Atomic Force Microscopy and Scanning Electron Microscopy. Macrophage-differentiated THP-1 cells proliferation and metabolic activity were assessed by qualitative and quantitative methods. The secretion of tumor necrosis factor alpha (TNF-α) and interleukin 10 (IL-10) cytokine, in the presence and absence of the inflammatory stimuli (bacterial endotoxin; lipopolysaccharide (LPS)), was measured using an ELISA assay. Our results revealed that the cellular response depended on the physical-chemical characteristics of the coatings. Copolymer-HA-Lf coatings led to low level of pro-inflammatory TNF-α, the increased level of anti-inflammatory IL-10, and the polarization of THP-1 cells towards an M2 pro-reparative phenotype in the presence of LPS. These findings could have important potential for the development of composite coatings in implant applications.

Complementarity of Matrix- and Nanostructure-Assisted Laser Desorption/Ionization Approaches

In recent years, matrix-assisted laser desorption/ionization (MALDI) has become the main tool for the study of biological macromolecules, such as protein nano-machines, especially in the determination of their molecular masses, structure, and post-translational modifications. A key role in the classical process of desorption and ionization of the sample is played by a matrix, usually a low-molecular weight weak organic acid. Unfortunately, the interpretation of mass spectra in the mass range of below m/z 500 is difficult, and hence the analysis of low molecular weight compounds in a matrix-assisted system is an analytical challenge. Replacing the classical matrix with nanomaterials, e.g., silver nanoparticles, allows improvement of the selectivity and sensitivity of spectrometric measurement of biologically important small molecules. Nowadays, the nanostructure-assisted laser desorption/ionization (NALDI) approach complements the classic MALDI in the field of modern bioanalytics. In particular, the aim of this work is to review the recent advances in MALDI and NALDI approaches.

Neuropharmacokinetic evaluation of lactoferrin-treated indinavir-loaded nanoemulsions: remarkable brain delivery enhancement

OBJECTIVE

Indinavir (IDV), an antiretroviral protease inhibitor used in treatment of HIV infection, has limited entry into brain due to efflux by the P-glycoprotein presented in blood-brain barrier. The aim of present study was to develop lactoferrin-treated nanoemulsion containing indinavir (Lf-IDV-NEs) for delivery to brain.

METHODS

Indinavir-loaded nanoemulsions (IDV-NEs) were prepared by high-speed homogenization method, and then lactoferrin was coupled to IDV-NEs by water soluble EDC method.

RESULTS

The hydrodynamic diameters, polydispersity index, and zeta potential of IDV-NEs were 112 ± 3.5 nm, 0.20 ± 0.02, and -33.2 ± 2.6 mV, respectively. From in vivo studies in animal model of rats, the AUC_0-4 h of brain concentration-time profile of IDV-NEs and Lf-IDV-NEs were 1.6 and 4.1 times higher than free drug, respectively. The brain uptake clearance of IDV-NEs and Lf-IDV-NEs were, interestingly, 393- and 420-times higher than the free drug.

CONCLUSIONS

It can be concluded that applying both lactoferrin-treated and non-treated nanoemulsions clearly leads to significant brain penetration enhancement of indinavir, an effect which is more pronounced in the case of Lf-IDV-NEs with the higher drug residence time in brain.

Gut microbiota: Role in pathogen colonization, immune responses, and inflammatory disease

The intestinal tract of mammals is colonized by a large number of microorganisms including trillions of bacteria that are referred to collectively as the gut microbiota. These indigenous microorganisms have co-evolved with the host in a symbiotic relationship. In addition to metabolic benefits, symbiotic bacteria provide the host with several functions that promote immune homeostasis, immune responses, and protection against pathogen colonization. The ability of symbiotic bacteria to inhibit pathogen colonization is mediated via several mechanisms including direct killing, competition for limited nutrients, and enhancement of immune responses. Pathogens have evolved strategies to promote their replication in the presence of the gut microbiota. Perturbation of the gut microbiota structure by environmental and genetic factors increases the risk of pathogen infection, promotes the overgrowth of harmful pathobionts, and the development of inflammatory disease. Understanding the interaction of the microbiota with pathogens and the immune system will provide critical insight into the pathogenesis of disease and the development of strategies to prevent and treat inflammatory disease.

Evaluation of the reproductive toxicity of antiretroviral drug loaded lactoferrin nanoparticles

Multiple prevention therapy has gained importance for the prevention and treatment of sexually transmitted diseases, especially HIV/AIDS. Antiretroviral drugs encapsulated in nanoparticles have been developed for efficient delivery of the drugs to the vaginal surface. Lactoferrin nanoparticles (LFNPs) encapsulating anticancer or antiretroviral drugs are found to be promising agents to specifically deliver drugs at the target sites. Recent studies indicate that the bioavailability is higher for antiretroviral drugs delivered by LFNPs than when the drugs are administered alone. Although LFNP-mediated drug delivery via the oral or vaginal route for the treatment of HIV/AIDS is promising, the effect of such administrations is not well studied. Drug-loaded LFNPs when administered to rats by the vaginal route did not show any effect on the reproductive performance, fertility, and postnatal development. Oral administration of drug-loaded LFNPs caused a significant decrease in litter size, whereas the reproductive performance and postnatal development remained normal. In our model system, the results indicate that vaginal administration of drug-loaded LFNPs appears safer and can be projected for the delivery of antiretroviral agents via the vaginal route. Abbreviations: LFNPs: lactoferrin nanoparticles; STIs: sexually transmitted diseases infections; NPs: nanoparticles; LF: lactoferrin; DL-LFNPs: drug loaded lactoferrin nanoparticles; MPT: multiple prevention techniques.

Surface Engineering of Nanoparticles for Targeted Delivery to Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is one of the leading causes of cancer-associated deaths worldwide. There is a lack of efficient therapy for HCC; the only available first-line systemic drug, sorafenib, can merely improve the average survival by two months. Among the efforts to develop an efficient therapy for HCC, nanomedicine has drawn the most attention, owing to its unique features such as high drug-loading capacity, intrinsic anticancer activities, integrated diagnostic and therapeutic functionalities, and easy surface engineering with targeting ligands. Despite its tremendous advantages, no nanomedicine can be effective unless it successfully targets the tumor site, which is a challenging task. In this review, the features of HCC are described, and the physiological hurdles that prevent nanoparticles from targeting HCC are discussed. Then, the surface physicochemical factors of nanoparticles that can influence targeting efficiency are discussed. Finally, a thorough description of the physiological barriers that nanomedicine must conquer before uptake by HCC cells if possible is provided, as well as the surface engineering approaches to nanomedicine to achieve targeted delivery to HCC cells. The physiological hurdles and corresponding solutions summarized in this review provide a general guide for the rational design of HCC targeting nanomedicine systems.

Iron Nutriture of the Fetus, Neonate, Infant, and Child

Iron is a key nutrient and is essential for the developing fetus, neonate, infant, and child. Iron requirements are high during early stages of life because it is critically important for the production of new red blood cells and muscle cells as well as brain development. Neonates, infants, and children obtain iron from dietary sources including breast milk (lactoferrin) and heme- and non-heme-containing foods. Iron deficiency (ID) is the most common micronutrient deficiency in children and pregnant women worldwide. ID and iron deficiency anemia (IDA) can affect growth and energy levels as well as motor and cognitive performance in the developing child. The fetus is completely dependent on maternal iron crossing through the placenta and, although it is generally well protected against deficiency at birth, ID in mothers can increase the risk of ID and IDA in their children as early as 4 months. This review will discuss the uses of iron, iron requirements, and the sources of iron from conception through childhood. In addition, it will describe the prevalence and clinical manifestations of ID and IDA in children and discuss recommendations for iron supplementation of children and pregnant women.

In vitro effectiveness of recombinant human lactoferrin and its hydrolysate in alleviating LPS-induced inflammatory response

This study aimed to evaluate the potential anti-inflammatory role of the most produced form of lactoferrin expressed in various expression systems (Fe-saturated recombinant human Lf, rhLf) and its hydrolysate in concentrations resembles that found in mature human milk. Co-culture model consisted of CaCo-2 and RAW 246.7 cell lines was used to evaluate the potential anti-inflammatory activity of rhLf and its hydrolysate. During this experiment, CaCo-2 monolayer permeability and integrity was assayed through the measurement of transepithelial electrical resistance (TEER values). Also, the production of reactive oxygen species (ROS), nitric oxide (NO) and different cytokines (IL-8, IL-1β, IL-6, IL-10, IL-12p70, and TNF-α) were measured. The treatment with rhLf and its hydrolysate protected the monolayer integrity against LPS effect and reduced IL-8 and ROS production. This effect was dependent on the dose and 2mgmL^-1 of rhLf hydrolysate was more effective. The addition of rhLf and its hydrolysate to infant formula is a prominent step towards improving both infant formula functionality and newborn health. Thus, these functional ingredients could be incorporated in infant foods. In this context, ongoing researches are conducted to clarify this effect whether by using synthetic peptides or by using LPS-sepsis animal.

Control of Phagocytosis by Microbial Pathogens

Phagocytosis is a fundamental process of cells to capture and ingest foreign particles. Small unicellular organisms such as free-living amoeba use this process to acquire food. In pluricellular organisms, phagocytosis is a universal phenomenon that all cells are able to perform (including epithelial, endothelial, fibroblasts, etc.), but some specialized cells (such as neutrophils and macrophages) perform this very efficiently and were therefore named professional phagocytes by Rabinovitch. Cells use phagocytosis to capture and clear all particles larger than 0.5 µm, including pathogenic microorganisms and cellular debris. Phagocytosis involves a series of steps from recognition of the target particle, ingestion of it in a phagosome (phagocytic vacuole), maturation of this phagosome into a phagolysosome, to the final destruction of the ingested particle in the robust antimicrobial environment of the phagolysosome. For the most part, phagocytosis is an efficient process that eliminates invading pathogens and helps maintaining homeostasis. However, several pathogens have also evolved different strategies to prevent phagocytosis from proceeding in a normal way. These pathogens have a clear advantage to perpetuate the infection and continue their replication. Here, we present an overview of the phagocytic process with emphasis on the antimicrobial elements professional phagocytes use. We also summarize the current knowledge on the microbial strategies different pathogens use to prevent phagocytosis either at the level of ingestion, phagosome formation, and maturation, and even complete escape from phagosomes.

Antidepressant-like effect of milk-derived lactoferrin in the repeated forced-swim stress mouse model

We investigated the antidepressant-like effect of lactoferrin (Lf) in a repeated forced-swim test (FST) stress mouse model. FST was performed on days 1, 2, 7 and 14. Bovine Lf (bLf) or bovine serum albumin (BSA) was supplemented at 1% to the commercial diet after the first FST throughout the experimental period. The FST-control and FST+BSA group showed a marked increase in immobility time on day 2, which remained increased up to the 14th day, while the FST+bLf group showed a significant lower immobility time. Brain-derived neurotrophic factor (BDNF) content in the hippocampus significantly decreased in all of FST treated groups. These results suggest that bLf may improve the depressive-like symptoms induced by repeated FST.

Extraordinarily potent proinflammatory properties of lactoferrin-containing immunocomplexes against human monocytes and macrophages

Lactoferrin (LTF), an important first line defense molecule against infection, is a common target for humoral autoimmune reactions in humans. Since LTF is a multifunctional protein capable of activating innate immune cells via various surface receptors, we hypothesized that LTF-containing immune complexes (ICs) (LTF-ICs), likely formed in patients with high titer anti-LTF autoantibodies, could possess unique monocyte/macrophage-activating properties compared with other ICs. ELISA analysis on serum samples from rheumatoid arthritis (RA) patients (n = 80) and healthy controls (n = 35) for anti-LTF autoantibodies confirmed a positive correlation between circulating LTF-specific IgG and RA. ICs between human LTF and LTF-specific IgG purified from patient sera or immunized rabbits and mice, but not control ICs, LTF or Abs alone, elicited strong production of TNF-α and IL-1β by freshly fractionated human peripheral blood monocytes and monocytes-derived macrophages. Furthermore, LTF-ICs utilized both membrane-anchored CD14 and CD32a (FcγRIIa) to trigger monocyte activation in an internalization-, Toll-like receptor (TLR)4- and TLR9-dependent manner, and also that LTF-IC-induced cytokine production was blocked by specific inhibitors of caspase-1, NF-κB and MAPK. These results uncover a possible pathway for LTF-ICs perpetuating local inflammation and contributing to the pathogenesis of autoimmune diseases by triggering activation of infiltrating monocytes or tissue macrophages in vivo.

Role of iron in the pathogenesis of respiratory disease

Iron is essential for many biological processes, however, too much or too little iron can result in a wide variety of pathological consequences, depending on the organ system, tissue or cell type affected. In order to reduce pathogenesis, iron levels are tightly controlled in throughout the body by regulatory systems that control iron absorption, systemic transport and cellular uptake and storage. Altered iron levels and/or dysregulated homeostasis have been associated with several lung diseases, including chronic obstructive pulmonary disease, lung cancer, cystic fibrosis, idiopathic pulmonary fibrosis and asthma. However, the mechanisms that underpin these associations and whether iron plays a key role in the pathogenesis of lung disease are yet to be fully elucidated. Furthermore, in order to survive and replicate, pathogenic micro-organisms have evolved strategies to source host iron, including freeing iron from cells and proteins that store and transport iron. To counter these microbial strategies, mammals have evolved immune-mediated defence mechanisms that reduce iron availability to pathogens. This interplay between iron, infection and immunity has important ramifications for the pathogenesis and management of human respiratory infections and diseases. An increased understanding of the role that iron plays in the pathogenesis of lung disease and respiratory infections may help inform novel therapeutic strategies. Here we review the clinical and experimental evidence that highlights the potential importance of iron in respiratory diseases and infections.

Apoptotic effects of bovine apo-lactoferrin on HeLa tumor cells

Lactoferrin (Lf), a cationic iron-binding glycoprotein of 80 kDa present in body secretions, is known as a compound with marked antimicrobial activity. In the present study, the apoptotic effect of iron-free bovine lactoferrin (apo-bLf) on human epithelial cancer (HeLa) cells was examined in association with reactive oxygen species and glutathione (GSH) levels. Apoptotic effect of iron-free bovine lactoferrin inhibited the growth of HeLa cells after 48 hours of treatment while the diferric-bLf was ineffective in the concentration range tested (from 1 to 12.5 μM). Western blot analysis showed that key apoptotic regulators including Bax, Bcl-2, Sirt1, Mcl-1, and PARP-1 were modulated by 1.25 μM of apo-bLf. In the same cell line, apo-bLf induced apoptosis together with poly (ADP-ribose) polymerase cleavage, caspase activation, and a significant drop of NAD⁺ . In addition, apo-bLf-treated HeLa cells showed a marked increase of reactive oxygen species level and a significant GSH depletion. On the whole, apo-bLf triggered apoptosis of HeLa cells upon oxygen radicals burst and GSH decrease.

Mechanisms of inflammation-driven bacterial dysbiosis in the gut

The gut microbiota has diverse and essential roles in host metabolism, development of the immune system and as resistance to pathogen colonization. Perturbations of the gut microbiota, termed gut dysbiosis, are commonly observed in diseases involving inflammation in the gut, including inflammatory bowel disease, infection, colorectal cancer and food allergies. Importantly, the inflamed microenvironment in the gut is particularly conducive to blooms of Enterobacteriaceae, which acquire fitness benefits while other families of symbiotic bacteria succumb to environmental changes inflicted by inflammation. Here we summarize studies that examined factors in the inflamed gut that contribute to blooms of Enterobacterieaceae, and highlight potential approaches to restrict Enterobacterial blooms in treating diseases that are otherwise complicated by overgrowth of virulent Enterobacterial species in the gut.

Intranasal delivery of rotigotine to the brain with lactoferrin-modified PEG-PLGA nanoparticles for Parkinson's disease treatment

Sustainable and safe delivery of brain-targeted drugs is highly important for successful therapy in Parkinson’s disease (PD). This study was designed to formulate biodegradable poly(ethylene glycol)–poly(lactic-co-glycolic acid) (PEG-PLGA) nanoparticles (NPs), which were surface-modified with lactoferrin (Lf), for efficient intranasal delivery of rotigotine to the brain for the treatment of PD. Rotigotine NPs were prepared by nanoprecipitation, and the effect of various independent process variables on the resulting properties of NPs was investigated by a Box–Behnken experimental design. The physicochemical and pharmaceutical properties of the NPs and Lf-NPs were characterized, and the release kinetics suggested that both NPs and Lf-NPs provided continuous, slow release of rotigotine for 48 h. Neither rotigotine NPs nor Lf-NPs reduced the viability of 16HBE and SH-SY5Y cells; in contrast, free rotigotine was cytotoxic. Qualitative and quantitative cellular uptake studies demonstrated that accumulation of Lf-NPs was greater than that of NPs in 16HBE and SH-SY5Y cells. Following intranasal administration, brain delivery of rotigotine was much more effective with Lf-NPs than with NPs. The brain distribution of rotigotine was heterogeneous, with a higher concentration in the striatum, the primary region affected in PD. This strongly suggested that Lf-NPs enable the targeted delivery of rotigotine for the treatment of PD. Taken together, these results demonstrated that Lf-NPs have potential as a carrier for nose-to-brain delivery of rotigotine for the treatment of PD.

The effects of differences in pspA alleles and capsular types on the resistance of Streptococcus pneumoniae to killing by apolactoferrin

Pneumococcal surface protein A (PspA) is the only pneumococcal surface protein known to strongly bind lactoferrin on the bacterial surface. In the absence of PspA Streptococcus pneumoniae becomes more susceptible to killing by human apolactoferrin (apo-hLf), the iron-free form of lactoferrin. In the present study we examined diverse strains of S. pneumoniae that differed by 2 logs in their susceptibility to apo-hLf. Among these strains, the amount of apo-hLf that bound to cell surface PspA correlated directly with the resistance of the strain to killing by apo-hLf. Moreover examination of different pspA alleles on shared genetic backgrounds revealed that those PspAs that bound more lactoferrin conferred greater resistance to killing by apo-hLf. The effects of capsule on killing of pneumococci by apo-hLf were generally small, but on one genetic background, however, the lack of capsule was associated with 4-times as much apo-hLf binding and 30-times more resistance to killing by apo-hLf. Overall these finding strongly support the hypothesis that most of the variation in the ability of apo-hLf is dependent on the variation in the binding of apo-hLf to surface PspA and this binding is dependent on variation in PspA as well as variation in capsule which may enhance killing by reducing the binding of apo-hLf to PspA.

Safety and Efficacy of a Milk-Derived Extract in the Treatment of Plaque Psoriasis: An Open-Label Study

Background:

XP-828L is a nutraceutical compound obtained by the extraction of a growth factors-enriched protein fraction from bovine milk. XP-828L may improve psoriasis.

Objectives:

An open-label study was performed to determine the efficacy, tolerability and safety of XP-828L in the treatment of plaque psoriasis.

Methods:

Eleven adult patients with chronic, stable plaque psoriasis on 2% or more of body surface area (BSA) received 5 g of oral XP-828L twice daily for 56 days.

Results:

All 11 patients completed the 56 days of treatment. At day 28, 6 of the 11 patients showed a reduction in PASI score. At 56 days, seven subjects had a decrease in PASI score ranging from 9.5% to 81.3%. Eight (8) out of 11 patients agreed to participate in an additional 8-week extension treatment phase. Improvement of psoriasis was maintained during the extension period. No clinically significant adverse events or laboratory abnormalities occurred.

Conclusion:

XP-828L may improve psoriasis in patients with mild-to-moderate psoriasis.

Pangolin genomes and the evolution of mammalian scales and immunity

Pangolins, unique mammals with scales over most of their body, no teeth, poor vision, and an acute olfactory system, comprise the only placental order (Pholidota) without a whole-genome map. To investigate pangolin biology and evolution, we developed genome assemblies of the Malayan (Manis javanica) and Chinese (M. pentadactyla) pangolins. Strikingly, we found that interferon epsilon (IFNE), exclusively expressed in epithelial cells and important in skin and mucosal immunity, is pseudogenized in all African and Asian pangolin species that we examined, perhaps impacting resistance to infection. We propose that scale development was an innovation that provided protection against injuries or stress and reduced pangolin vulnerability to infection. Further evidence of specialized adaptations was evident from positively selected genes involving immunity-related pathways, inflammation, energy storage and metabolism, muscular and nervous systems, and scale/hair development. Olfactory receptor gene families are significantly expanded in pangolins, reflecting their well-developed olfaction system. This study provides insights into mammalian adaptation and functional diversification, new research tools and questions, and perhaps a new natural IFNE-deficient animal model for studying mammalian immunity.

Iron acquisition in Leishmania and its crucial role in infection

Iron is an essential cofactor for many basic metabolic pathways in pathogenic microbes and their hosts. It is also dangerous as it can catalyse the production of reactive free radicals. This dual character makes the host can either limit iron availability to invading microbes or exploit iron to induce toxicity to pathogens. Successful pathogens, including Leishmania species, must possess mechanisms to circumvent host's iron limitation and iron-induced toxicity in order to survive. In this review, we discuss the regulation of iron metabolism in the setting of infection and delineate the iron acquisition strategies used by Leishmania parasites and their subversions to host iron metabolism to overcome host's iron-related defences.

Lactoferrin Decreases the Intestinal Inflammation Triggered by a Soybean Meal-Based Diet in Zebrafish

Intestinal inflammation is a harmful condition in fish that can be triggered by the ingestion of soybean meal. Due to the positive costs-benefits ratio of including soybean meal in farmed fish diets, identifying additives with intestinal anti-inflammatory effects could contribute to solving the issues caused by this plant protein. This study evaluated the effect of incorporating lactoferrin (LF) into a soybean meal-based diet on intestinal inflammation in zebrafish. Larvae were fed with diets containing 50% soybean meal (50SBM) or 50SBM supplemented with LF to 0.5, 1, 1.5 g/kg (50SBM+LF0.5; 50SBM+LF1.0; 50SBM+LF1.5). The 50SBM+LF1.5 diet was the most efficient and larvae had a reduced number of neutrophils in the intestine compared with 50SBM larvae and an indistinguishable number compared with control larvae. Likewise, the transcription of genes involved in neutrophil migration and intestinal mucosal barrier functions (mmp9, muc2.2, and β-def-1) were increased in 50SBM larvae but were normally expressed in 50SBM+LF1.5 larvae. To determine the influence of intestinal inflammation on the general immune response, larvae were challenged with Edwardsiella tarda. Larvae with intestinal inflammation had increased mortality rate compared to control larvae. Importantly, 50SBM+LF1.5 larvae had a mortality rate lower than control larvae. These results demonstrate that LF displays a dual effect in zebrafish, acting as an intestinal anti-inflammatory agent and improving performance against bacterial infection.

Triple combination MPT vaginal microbicide using curcumin and efavirenz loaded lactoferrin nanoparticles

We report that a combination of anti-HIV-1 drug efavirenz (EFV), anti-microbial-spermicidal curcumin (Cur) and lactoferrin nanoparticles (ECNPs) act as MPT formulation. These nanoparticles are of well dispersed spherical shape with 40–70 nm size, with encapsulation efficiency of 63 ± 1.9% of Cur & 61.5% ± 1.6 of EFV, significantly higher than that of single drug nanoparticles (Cur, 59 ± 1.34%; EFV: 58.4 ± 1.79). ECNPs were found to be sensitive at pH 5 and 6 and have not effected viability of vaginal micro-flora, Lactobacillus. Studies in rats showed that ECNPs delivers 88–124% more drugs in vaginal lavage as compared to its soluble form, either as single or combination of EFV and Cur. The ECNPs also shows 1.39–4.73 fold lower concentration of absorption in vaginal tissue and plasma compared to soluble EFV + Cur. Furthermore, ECNPs show significant reduction in inflammatory responses by 1.6–3.0 fold in terms of IL-6 and TNF-α in vaginal tissue and plasma compared to soluble EFV + Cur. ECNPs showed improved pharmacokinetics profiles in vaginal lavage with more than 50% of enhancement in AUC, AUMC, C_max and t_1/2 suggesting longer exposure of Cur and EFV in vaginal lavage compared to soluble EFV + Cur. Histopathological analysis of vaginal tissue shows remarkably lower toxicity of ECNPs compared to soluble EFV + Cur. In conclusion, ECNPs are significantly safe and exhibit higher bioavailability thus constitute an effective MPT against HIV.

Transcriptomics: the key to biomarker discovery during tuberculosis?

Tuberculosis is a global threat affecting millions of people and requires more efficient methods of diagnosis, monitoring treatment response and the development of more efficacious drug therapies and new vaccines. The use of transcriptomic approaches and gene expression techniques have contributed to the elucidation of these aspects concerning the study of tuberculosis, and more specifically, the utilization of transcriptional profiles to identify biomarkers. These markers are the key to developing tools required to improve diagnosis and treatment of tuberculosis. Several studies have led to the identification of markers able to distinguish between different infection states, as well as other pulmonary diseases. Utilizing a systems biology approach will assist in obtaining more reliable results, leading to the implementation of significant findings.

Efficacy of Bovine Lactoferrin Supplementation in Preventing Late-onset Sepsis in low Birth Weight Neonates: A Randomized Placebo-Controlled Clinical Trial

OBJECTIVES

To evaluate the efficacy of bovine lactoferrin (BLF) in preventing first episode of late-onset sepsis (LOS) in low birth weight (LBW) neonates.

METHODS

In this study conducted from May 2012 to July 2013 in the neonatal intensive care unit (NICU) of a tertiary care hospital, inborn asymptomatic neonates, <2000 g, admitted to NICU in first 12 h of birth with no maternal risk factors for sepsis were randomized to receive BLF or placebo from 1st to 28th day of life. The incidence of culture-proven sepsis and sepsis-attributable mortality after 72 h of life was recorded. Increasing doses of BLF were used with higher birth weights.

RESULTS

Incidence of first episode of culture-proven LOS was significantly lower in the BLF group vs. placebo [2/63 (3.2%) vs. 9/67(13.4%); risk ratio, 0.211; 95% CI, 0.044-1.019; p = 0.036]. Statistically significant reduction in the sepsis-attributable mortality was also seen after use of prophylactic BLF [0/63 (0%) vs. 5/67 (7.5%); p = 0.027].

CONCLUSION

BLF supplementation in LBW neonates reduced the incidence of first episode of LOS.

Lactoferrin-modified PEGylated liposomes loaded with doxorubicin for targeting delivery to hepatocellular carcinoma

Lactoferrin (Lf) is a potential-targeting ligand for hepatocellular carcinoma (HCC) cells because of its specific binding with asialoglycoprotein receptor (ASGPR). In this present work, a doxorubicin (DOX)-loaded, Lf-modified, polyethylene glycol (PEG)ylated liposome (Lf-PLS) system was developed, and its targeting effect and antitumor efficacy to HCC was also explored. The DOX-loaded Lf-PLS system had spherical or oval vesicles, with mean particle size approximately 100 nm, and had an encapsulation efficiency of 97%. The confocal microscopy and flow cytometry indicated that the cellular uptake of Lf-PLS was significantly higher than that of PEGylated liposome (PLS) in ASGPR-positive cells (P<0.05) but not in ASGPR-negative cells (P>0.05). Cytotoxicity assay by MTT demonstrated that DOX-loaded Lf-PLS showed significantly stronger antiproliferative effects on ASGPR-positive HCC cells than did PLS without the Lf modification (P<0.05). The in vivo antitumor studies on male BALB/c nude mice bearing HepG2 xenografts demonstrated that DOX-loaded Lf-PLS had significantly stronger antitumor efficacy compared with PLS (P<0.05) and free DOX (P<0.05). All these results demonstrated that a DOX-loaded Lf-PLS might have great potential application for HCC-targeting therapy.

Fabrication mechanism and structural characteristics of the ternary aggregates by lactoferrin, pectin, and (-)-epigallocatechin gallate using multispectroscopic methods

The ternary aggregates were fabricated by lactoferrin (LF), pectin (high methylated pectin (HMP)/low methylated pectin (LMP)), and (-)-epigallocatechin gallate (EGCG) through three different fabrication methods at pH 5.0. The turbidity, particle size, and ζ-potential of ternary aggregates were influenced by the types of pectin, the concentration of EGCG, and fabrication methods. The fluorescence intensity of LF decreased with an increase in EGCG concentration for all ternary aggregates. Far-UV circular dichroism results indicated that EGCG could alter the secondary structure of LF with an increase in the proportion of β-sheet structure at the cost of unordered coil structure. According to near-UV circular dichroism results, EGCG could also modulate the tertiary structure of LF at the presence of pectin. In addition, EGCG could increase the viscoelasticity of the ternary aggregates with HMP, leading to better stability of the ternary aggregates. An opposite result was observed for the ternary aggregates with LMP. These findings should provide an insight into the fabrication mechanism and applications of ternary aggregates formed by protein, polysaccharide, and polyphenol in the food, pharmaceutical, and cosmetic industries.

Structural characterization and functional evaluation of lactoferrin–polyphenol conjugates formed by free-radical graft copolymerization

Covalent modifications of lactoferrin with EGCG, chlorogenic acid and gallic acid were performed by adopting a free-radical grafting procedure in aqueous media and they affect both structural and functional properties of the protein.

Glycosylation improves the functional characteristics of chlorogenic acid–lactoferrin conjugate

Chlorogenic acid (CA)–lactoferrin (LF) conjugate prepared via alkali treatment was glycoslated with glucose (Glc) or polydextrose (PD) by the Maillard reaction, and the modification improved the functional properties of the conjugate.

The Immunology of Mammary Gland of Dairy Ruminants between Healthy and Inflammatory Conditions

The health of dairy animals, particularly the milk-producing mammary glands, is essential to the dairy industry because of the crucial hygienic and economic aspects of ensuring production of high quality milk. Due to its high prevalence, mastitis is considered the most important threat to dairy industry, due to its impacts on animal health and milk production and thus on economic benefits. The MG is protected by several defence mechanisms that prevent microbial penetration and surveillance. However, several factors can attenuate the host immune response (IR), and the possession of various virulence and resistance factors by different mastitis-causing microorganisms greatly limits immune defences and promotes establishment of intramammary infections (IMIs). A comprehensive understanding of MG immunity in both healthy and inflammatory conditions will be an important key to understand the nature of IMIs caused by specific pathogens and greatly contributes to the development of effective control methods and appropriate detection techniques. Consequently, this review aims to provide a detailed overview of antimicrobial defences in the MG under healthy and inflammatory conditions. In this sense, we will focus on pathogen-dependent variations in IRs mounted by the host during IMI and discuss the potential ramifications of these variations.

Native and thermally modified protein-polyphenol coassemblies: lactoferrin-based nanoparticles and submicrometer particles as protective vehicles for (-)-epigallocatechin-3-gallate

The interactions between native, thermally modified lactoferrin (LF) and (-)-epigallocatechin-3-gallate (EGCG) at pH 3.5, 5.0, and 6.5 were investigated. Turbidity, particle size, and charge of LF-EGCG complexes were mainly dominated by pH value and secondary structure of protein. At pH 3.5 and 5.0, LF-EGCG complexes were nanoparticles which had high ζ-potential, small size, and soluble state. At pH 6.5, they were submicrometer particles which exhibited low ζ-potential, large size, and insoluble state. The infrared spectra of freeze-dried LF-EGCG complexes showed that they were different from LF and EGCG alone. Far-UV CD results indicated that heat denaturation might irreversibly alter the secondary structure of LF and EGCG induced a progressive increase in the proportion of α-helix structure at the cost of β-sheet and unordered coil structure of LF at pH 3.5, 5.0, and 6.5. EGCG exhibited a strong affinity for native LF but a weak affinity for thermally modified LF at pH 5.0 and 6.5. An inverse result was observed at pH 3.5. These results could have potential for the development of food formulations based on LF as a carrier of bioactive compounds.