Properties Of Lectin Research Articles

Revisiting legume lectins: Structural organization and carbohydrate-binding properties

Legume lectins are a diverse family of carbohydrate-binding proteins that share significant similarities in their primary, secondary, and tertiary structures, yet exhibit remarkable variability in their quaternary structures and carbohydrate-binding specificities. The tertiary structure of legume lectins, characterized by a conserved β-sandwich fold, provides the scaffold for the formation of a carbohydrate-recognition domain (CRD) responsible for ligand binding. The structural basis for the binding is similar between members of the family, with key residues interacting with the sugar through hydrogen bonds, hydrophobic interactions, and van der Waals forces. Variability in substructures and residues within the CRD are responsible for the large array of specificities and enable legume lectins to recognize diverse sugar structures, while maintaining a consistent structural fold. Therefore, legume lectins can be classified into several specificity groups based on their preferred ligands, including mannose/glucose-specific, N-acetyl-d-galactosamine/galactose-specific, N-acetyl-d-glucosamine-specific, l-fucose-specific, and α-2,3 sialic acid-specific lectins. In this context, this review examined the structural aspects and carbohydrate-binding properties of representative legume lectins and their specific ligands in detail. Understanding the structure/binding relationships of lectins continues to provide valuable insights into their biological roles, while also assisting in the potential applications of these proteins in glycobiology, diagnostics, and therapeutics.

A Review of the Leishmanicidal Properties of Lectins.

Lectins are proteins widely distributed among plants, animals and microorganisms that have the ability to recognize and interact with specific carbohydrates. They have varied biological activities, such as the inhibition of the progression of infections caused by fungi, bacteria, viruses and protozoa, which is related to the interaction of these proteins with the carbohydrates present in the cell walls of these microorganisms. Leishmaniasis are a group of endemic infectious diseases caused by protozoa of the genus Leishmania. In vitro and in vivo tests with promastigotes and amastigotes of Leishmania demonstrated that lectins have the ability to interact with glycoconjugates present on the cell surface of the parasite, it prevents their development through various mechanisms of action, such as the production of ROS and alteration of membrane integrity, and can also interact with defense cells present in the human body, thus showing that these molecules can be considered alternative pharmacological targets for the treatment of leishmaniasis. The objective of the present work is to carry out a bibliographic review on lectins with leishmanicidal activity, emphasizing the advances and perspectives of research in this theme. Through the analysis of the selected studies, we were able to conclude that lectins have great potential for inhibiting the development of leishmaniasis. However, there are still few studies on this subject.

Isolation, characterization and antimicrobial properties of hepatopancreas lectin of the freshwater crab Oziotelphusanaga

Lectins are versatile proteins that specifically recognize and interact with sugar moieties expressed on the cell surface. The potential of lectin in drug targeting and delivery has instigated interest to identify natural lectins. Crabs have been identified as a rich source of lectin because the innate immune system is activated on encounter of pathogens and helps in the production of lectin. Although the presence of lectins in crab's hemolymph is well documented, little information about lectin in hepatopancreas, a vital organ for immunity and digestion in crustaceans, is currently available. A calcium dependent lectin (75 kDa) was purified from the hepatopancreas of the freshwater crab Oziotelphusa naga by bioadsorption and fetuin linked Sepharose 4B affinity chromatography technique. The isolated hepatopancreas lectin is calcium dependent and maximum agglutination was observed with rabbit erythrocytes. The hemagglutinating activity of the hepatopancreas lectin was effectively inhibited by sugars, such as α-lactose, GlcNAc, trehalose and NeuAc. Compared to sialylated N-glycosylated proteins including transferrin and apo transferrin, sialylated O-glycosylated proteins like fetuin exhibited stronger inhibitory effect. The ability of erythrocytes to bind hepatopancreas lectin has been diminished by desialylation of the potent inhibitor, indicating the significance of sialic acid in lectin-ligand interactions. The purified hepatopancreas lectin showed a broad spectrum of antimicrobial activity against bacteria Staphylococcus aureus, Klebsiella pneumoniae, Proteus mirabilis, Pseudomonas aeruginosa, E. coli and fungi Candida albicans and Aspergillus niger. The findings of this study demonstrate the significance of hepatopancreas lectin as a multifunctional defense protein that inhibits the growth of bacteria and fungi.

Leveraging Lucrative Lectins: An Explorative Review of the Biomedical Properties of Lectins

Leveraging Lucrative Lectins: An Explorative Review of the Biomedical Properties of Lectins

Alocasia macrorrhiza rhizome lectin inhibits growth of pathogenic bacteria and human lung cancer cell in vitro and Ehrlich ascites carcinoma cell in vivo in mice

Cancer and antibiotic resistance represent significant global challenges, affecting public health and healthcare systems worldwide. Lectin, a carbohydrate-binding protein, displays various biological properties, including antimicrobial and anticancer activities. This study focused on anticancer and antibacterial properties of Alocasia macrorrhiza lectin (AML). AML, with a molecular weight of 11.0 ± 1.0 kDa was purified using Ion-exchange chromatography, and the homotetrameric form was detected by gel-filtration chromatography. It agglutinates mouse erythrocytes, that was inhibited by 4-Nitrophenyl-α-d-mannopyranoside. Maximum hemagglutination activity was observed below 60 °C and within a pH range from 8 to 11. Additionally, it exhibited moderate toxicity against brine shrimp nauplii with LD50 values of 321 μg/ml and showed antibacterial activity against Escherichia coli and Shigella dysenteriae. In vitro experiments demonstrated that AML suppressed the proliferation of mice Ehrlich ascites carcinoma (EAC) cells by 35 % and human lung cancer (A549) cells by 40 % at 512 μg/ml concentration. In vivo experiments involved intraperitoneal injection of AML in EAC-bearing mice for five consecutive days at doses of 2.5 and 5.0 mg/kg/day, and the results indicated that AML inhibited EAC cell growth by 37 % and 54 %, respectively. Finally, it can be concluded that AML can be used for further anticancer and antibacterial studies.

Entomotoxic Properties of White Kidney Bean and Soybean Lectins and their Effects against Two Digestive Enzymes of the Spiny Bollworm, Earias insulana (Boisd.)

Entomotoxic Properties of White Kidney Bean and Soybean Lectins and their Effects against Two Digestive Enzymes of the Spiny Bollworm, Earias insulana (Boisd.)

Properties of lectin from tissue culture of Ungernia victoris and its ultrasonic extraction

The aim was to investigate biomass extracts of U. victoris strain UV-2 tissue culture for the content of lectins, to study their general characteristics and to optimize the method of ultrasonic extraction to obtain a soluble form of the lectin. Methods. Tissue culture method, direct hemagglutination test for detection of lectin activity (LA), determination of lectin carbohydrate specificity, ultrasonic extraction method. The results. Lectin activity was detected in the soluble (supernatant) and insoluble (sediment) fractions of the extract of biomass U. victoris tissue culture. In the soluble fraction LA was significantly less compared to that in the sediment, which indicated the presence of the membrane-bound form of the lectin. LA was characterized by pronounced species specificity: the reaction with mouse erythrocytes was the most intense. The study of carbohydrate specificity revealed a weak affinity for monosugars (galactose and galactosamine) and pronounced suppression of LA in the case of polysaccharides - hyaluronic acid, heparin and mucin. The possibilities of the ultrasound extraction method for separation the detected lectin from the the cell surface in the sediment fraction were investigated and the extraction procedure was optimized. The transition of LA into the soluble phase under the influence of ultrasound depended on the following parameters: the concentration and volume of the extract, as well as the time of exposure to ultrasound. It was established that the LA of the soluble phase doubled compared to the initial one with an extract concentration of 50 mg/ml and a volume of 20 ml under the action of ultrasound 40 kHz/70 W in the interval of 15-45 minutes. Longer ultrasound treatment had a negative effect on LA. Conclusions. Lectin activity of U. victoris tissue culture biomass extracts was discovered for the first time, which can become a promising source of lectin with a wide spectrum of pharmacological properties. The general characteristics of the lectin were given, and its species and carbohydrate specificity was revealed. The lectin was generally characterized and its species and carbohydrate specificity were established. Possibilities of ultrasound extraction were used and the procedure was optimized to obtain a soluble form of the lectin, necessary for its further fundamental and practical research.

Heterophyllin: A New Adenia Toxic Lectin with Peculiar Biological Properties.

Ribosome-inactivating proteins (RIPs) are plant toxins that were identified for their ability to irreversibly damage ribosomes, thereby causing arrest of protein synthesis and induction of cell death. The RIPs purified from Adenia plants are the most potent ones. Here, we describe a novel toxic lectin from Adenia heterophylla caudex, which has been named heterophyllin. Heterophyllin shows the enzymatic and lectin properties of type 2 RIPs. Interestingly, in immunoreactivity experiments, heterophyllin poorly cross-reacts with sera against all other tested RIPs. The cytotoxic effects and death pathways triggered by heterophyllin were investigated in three human-derived cell lines: NB100, T24, and MCF7, and compared to ricin, the most known and studied type 2 RIP. Heterophyllin was able to completely abolish cell viability at nM concentration. A strong induction of apoptosis, but not necrosis, and the involvement of oxidative stress and necroptosis were observed in all the tested cell lines. Therefore, the enzymatic, immunological, and biological activities of heterophyllin make it an interesting molecule, worthy of further in-depth analysis to verify its possible pharmacological application.

A knockdown gene approach identifies an insect vector membrane protein with leucin-rich repeats as one of the receptors for the VmpA adhesin of flavescence dorée phytoplasma.

The adhesion of flavescence dorée phytoplasma to the midgut epithelium cells of their insect vectors is partially mediated by the variable membrane protein A (VmpA), an adhesin which shows lectin properties. In order to identify the insect receptor for VmpA, we identified Euscelidius variegatus cell proteins interacting with recombinant VmpA-His6. The E. variegatus proteins were identified by mass spectrometry analysis of VmpA-E. variegatus protein complexes formed upon in vitro interaction assays. To assess their impact in VmpA binding, we reduced the expression of the candidate genes on E. variegatus cells in culture by dsRNA-mediated RNAi. The effect of candidate gene knockdown on VmpA binding was measured by the capacity of E. variegatus cells to bind VmpA-coated fluorescent beads. There were 13 candidate proteins possessing potential N-glycosylation sites and predicted transmembrane domains selected. The decrease of expression of an unknown transmembrane protein with leucine-rich repeat domains (uk1_LRR) was correlated with the decreased adhesion of VmpA beads to E. variegatus cells. The uk1_LRR was more expressed in digestive tubes than salivary glands of E. variegatus. The protein uk1_LRR could be implicated in the binding with VmpA in the early stages of insect infection following phytoplasmas ingestion.

Purification, Characterization and Antimicrobial Properties of Hemolymph Lectin from the Larva of Red Palm Weevil, Rhynchophorus ferrugineus

Lectins are renowned hemagglutinins and multivalent proteins with a well-known quality for sugar-binding specificity that participate significantly in invertebrate defense functions. Studies on biological activity of lectin from coleopteran insect are very scarce. A lectin with specific affinity for N-acetyl neuraminic acid was purified from the hemolymph of the larva of the red palm weevil, Rhynchophorus ferrugineus by biospecific adsorption using formalinized rabbit erythrocytes and affinity chromatography using PSM-linked cyanogen bromide activated Sepharose 4B. The specific activity of the lectin purified by affinity chromatography was much higher than the lectin purified by biospecific adsorption. The binding specificity of the weevil lectin distinguishes it from other known insect lectins. Like the crude agglutinin, the lectin purified by affinity chromatography also showed the same pattern of specificity towards erythrocytes. However, 4-to-8-fold decrease in HA titer was observed when tested with the purified lectin. In the same way, reduction is also observed in the HAI titer of the purified lectin with most of the inhibitors except PSM where the HAI titer was identical both in the crude agglutinin and purified lectin. Sugars N-acetyl neuraminic acid, N-acetyl mannosamine and N-acetyl-D-galactosamine inhibited the HA titer of the purified lectin with greater efficacy than the crude agglutinin. The sialic acid specificity of the lectin was confirmed by 16-fold reduction in HA titer with asialo rabbit erythrocytes and 32-fold reduction in HAI titer with desialylated PSM. The purified lectin is homogenous on sodium dodecyl sulphate-polyacrylamide electrophorogram with a molecular weight of about 60 kDa. The lectin showed antimicrobial activity against pathogenic bacteria Streptococcus mutans, Escherichia coli, Klebsiella pneumoniae and Pseudomonas aeroginosa and fungi Candida albicans and Aspergillus niger.

Lectin-Seq: A method to profile lectin-microbe interactions in native communities.

Soluble human lectins are critical components of innate immunity. Genetic models suggest that lectins influence host-resident microbiota, but their specificity for commensal and mutualist species is understudied. Elucidating lectins' roles in regulating microbiota requires an understanding of which microbial species they bind within native communities. To profile human lectin recognition, we developed Lectin-Seq. We apply Lectin-Seq to human fecal microbiota using the soluble mannose-binding lectin (MBL) and intelectin-1 (hItln1). Although each lectin binds a substantial percentage of the samples (10 to 20%), the microbial interactomes of MBL and hItln1 differ markedly in composition and diversity. MBL binding is highly selective for a small subset of species commonly associated with humans. In contrast, hItln1's interaction profile encompasses a broad range of lower-abundance species. Our data uncover stark differences in the commensal recognition properties of human lectins.

Multivalent lectin-carbohydrate interactions: Energetics and mechanisms of binding.

The biological signaling properties of lectins, which are carbohydrate-binding proteins, are due to their ability to bind and cross-link multivalent glycoprotein receptors on the surface of normal and transformed cells. While the cross-linking properties of lectins with multivalent carbohydrates and glycoproteins are relatively well understood, the mechanisms of binding of lectins to multivalent glycoconjugates are less well understood. Recently, the thermodynamics of binding of lectins to synthetic clustered glycosides, a multivalent globular glycoprotein, and to linear glycoproteins (mucins) have been described. The results are consistent with a dynamic binding mechanism in which lectins bind and jump from carbohydrate to carbohydrate epitope in these molecules. Importantly, the mechanism of binding of lectins to mucins is similar to that for a variety of protein ligands binding to DNA. Recent analysis also shows that high-affinity lectin-mucin cross-linking interactions are driven by favorable entropy of binding that is associated with the bind and jump mechanism. The results suggest that the binding of ligands to biopolymers, in general, may involve a common mechanism that involves enhanced entropic effects which facilitate binding and subsequent complex formation including enzymology.

Structure and Biological Properties of Ribosome-Inactivating Proteins and Lectins from Elder (Sambucus nigra L.) Leaves.

Ribosome-inactivating proteins (RIPs) are a group of proteins with rRNA N-glycosylase activity that catalyze the removal of a specific adenine located in the sarcin–ricin loop of the large ribosomal RNA, which leads to the irreversible inhibition of protein synthesis and, consequently, cell death. The case of elderberry (Sambucus nigra L.) is unique, since more than 20 RIPs and related lectins have been isolated and characterized from the flowers, seeds, fruits, and bark of this plant. However, these kinds of proteins have never been isolated from elderberry leaves. In this work, we have purified RIPs and lectins from the leaves of this shrub, studying their main physicochemical characteristics, sequences, and biological properties. In elderberry leaves, we found one type 2 RIP and two related lectins that are specific for galactose, four type 2 RIPs that fail to agglutinate erythrocytes, and one type 1 RIP. Several of these proteins are homologous to others found elsewhere in the plant. The diversity of RIPs and lectins in the different elderberry tissues, and the different biological activities of these proteins, which have a high degree of homology with each other, constitute an excellent source of proteins that are of great interest in diagnostics, experimental therapy, and agriculture.

A review of thermosensitive antinutritional factors in plant-based foods.

Legumes and cereals account for the vast proportion of people's daily intake of plant-based foods. Meanwhile, a large number of antinutritional factors in legumes and cereals hinder the body absorption of nutrients and reduce the nutritional value of food. In this paper, the antinutritional effects, determination, and passivation methods of thermosensitive antinutritional factors such as trypsin inhibitors, urease, lipoxygenase, and lectin were reviewed to provide theoretical help to reduce antinutritional factors in food and improve the utilization rate of plant-based food nutrition. Since trypsin inhibitors and lectin have been more extensively studied and reviewed previously, the review mainly focused on urease and lipoxygenase. This review summarized the information of thermosensitive antinutritional factors, trypsin inhibitors, urease, lipoxygenase, and lectin, in cereals and legumes. The antinutritional effects, and physical and chemical properties of trypsin inhibitors, urease, lipoxygenase, and lectin were introduced. At the same time, the research methods for the detection and inactivation of these four antinutritional factors were also summarized in the order of research conducted time. The rapid determination and inactivation of antinutrients will be the focus of attention for the food industry in the future to improve the nutritional value of food. Exploring what structural changes could passivation technologies bring to antinutritional factors will provide a theoretical basis for further understanding the mechanisms of antinutritional factor inactivation. PRACTICAL APPLICATIONS: Antinutritional factors in plant-based foods hinder the absorption of nutrients and reduce the nutritional value of the food. Among them, thermosensitive antinutritional factors, such as trypsin inhibitors, urease, lipoxygenase, and lectins, have a high proportion among the antinutritional factors. In this paper, we investigate thermosensitive antinutritional factors from three perspectives: the antinutritional effect of thermosensitive antinutritional factors, determination, and passivation methods. The current passivation methods for thermosensitive antinutritional factors revolve around biological, physical, and chemical aspects, and their elimination mechanisms still need further research, especially at the protein structure level. Reducing the level of antinutritional factors in the future food industry while controlling the loss of other nutrients in food is a goal that needs to be balanced. This paper reviews the antinutritional effects of thermosensitive antinutritional factors and passivation methods, expecting to provide new research ideas to improve the nutrient utilization of food.

Prokaryotic expression, purification, physicochemical properties and antifungal activity analysis of phloem protein PP2-A1 from cucumber

Phloem protein 2 (PP2) is a protein having lectin properties that can be isolated from the phloem sap. Based on our previous proteomic study of phloem sap of Cucumis sativus, it was found that the expression of PP2 A1-like was significantly up-regulated under salt stress, which may be a molecular mechanism of plant adaptation to stress. This paper carried out the expression and purification of the CsPP2-A1 gene in E. coli for further characteristic analysis. The results demonstrated that the CsPP2-A1 in shake flask cultures was mainly expressed in the soluble form at 15 °C or in inclusion bodies at 37 °C. Secondly, Ni-IDA affinity chromatography and SDS-PAGE were employed to yield highly purified CsPP2-A1 protein. The purified CsPP2-A1 was then subjected to Western blot and MALDI-TOF-MS analysis for protein identification. The biological activity analysis results showed that CsPP2-A1 had hemagglutinating activities to rabbit erythrocytes, and Chitotetraose may be the specific inhibitory sugar of CsPP2-A1. The optimal hemagglutination activity of CsPP2-A1 protein was achieved between pH 5–9, and between 20 and 60 °C. Moreover, CsPP2-A1 had significant inhibitory effects on Botrytis cinerea and Phytophthora infestans, and the inhibitory effect on B. cinerea was better than that on P. infestans.

The Use of Lectins as Tools to Combat SARS-CoV-2.

In December 2019, China announced the first case of an infection caused by an, until then, unknown virus: SARS-CoV-2. Since then, researchers have been looking for viable alternatives for the treatment and/or cure of viral infection. Among the possible complementary solutions are lectins, proteins that are reversibly bound to different carbohydrates. The Spike protein, present on the viral surface, can interact with different cell receptors: ACE2, CD147, and DC-SIGNR. Since lectins have an affinity for different carbohydrates, the binding with the glycosylated cell receptors represents a possibility of preventing the virus from binding to the receptors of host cells. In this review, we discuss the main lectins that are possible candidates for use in the treatment of Covid-19, highlighting those that have already demonstrated antiviral activity in vivo and in vitro, including mannose-binding lectin, Griffithsin, BanLec, and others. We also aim to discuss the possible mechanism of action of lectins, which appears to occur through the mediation of viral fusion in host cells, by binding of lectins to glycosylated receptors found in human cells and/or binding of these proteins with the spike glycoprotein, present in virus surface. Moreover, we discuss the use of lectins in clinical practice. Even with the development of effective vaccines, new cases of viral infection with the same virus, or new outbreaks with different viruses can occur; so, the development of new treatments should not be discarded. Moreover, the discussions made in this work are relevant regarding the anti-viral properties of lectins.

The Two Sweet Sides of Janus Lectin Drive Crosslinking of Liposomes to Cancer Cells and Material Uptake.

A chimeric, bispecific Janus lectin has recently been engineered with different, rationally oriented recognition sites. It can bind simultaneously to sialylated and fucosylated glycoconjugates. Because of its multivalent architecture, this lectin reaches nanomolar avidities for sialic acid and fucose. The lectin was designed to detect hypersialylation—a dysregulation in physiological glycosylation patterns, which promotes the tumor growth and progression of several cancer types. In this study, the characteristic properties of this bispecific Janus lectin were investigated on human cells by flow cytometry and confocal microscopy in order to understand the fundamentals of its interactions. We evaluated its potential in targeted drug delivery, precisely leading to the cellular uptake of liposomal content in human epithelial cancer cells. We successfully demonstrated that Janus lectin mediates crosslinking of glyco-decorated giant unilamellar vesicles (GUVs) and H1299 lung epithelial cells. Strikingly, the Janus lectin induced the internalization of liposomal lipids and also of complete GUVs. Our findings serve as a solid proof of concept for lectin-mediated targeted drug delivery using glyco-decorated liposomes as possible drug carriers to cells of interest. The use of Janus lectin for tumor recognition certainly broadens the possibilities for engineering diverse tailor-made lectin constructs, specifically targeting extracellular structures of high significance in pathological conditions.

In English

Сombination of properties of lectins and magnetically sensitive iron-containing nanocomposites (NC) for use in oncology is actual and promising from scientific and applied point of view. The aim of the research is to synthesize and to study new iron-containing NC and magnetic fluids containing bioactive bacterial lectin, promising for use as prototypes of new effective antitumor vector systems for targeted drug delivery and combined local therapy of cancer with minimized side effects on the body and improved compatibility with other remedies. To create vector systems, nanodisperse magnetite was synthesized by the Elmore reaction. The synthesis of aluminum-containing coating on the surface of Fe3O4 was carried out by double chemical modification with aluminum isopropylate. The obtained Fe3O4/Al2O3 NC was impregnated with sucrose solutions. Carbonization of the carbohydrate shell of NC was carried out in argon (500 °C). As a result, Fe3O4/Al2O3/C NC was obtained. The magnetic properties of nanostructures were measured using a laboratory vibration magnetometer of Foner type at room temperature. Adsorption immobilization of lectin was performed in 0.9 % NaCl solution in a dynamic mode at room temperature. Bacterial cytotoxic lectin of B. subtilis IMB B-7724 was used in the experiments. The amount of adsorbed substance (A) on the surface of nanocomposites was determined by measuring the concentration of lectin in the contact solutions before and after adsorption using a calibration graph. Measuring of the optical density and absorption spectra of lectin was performed on a spectrometer Lambda 35 UV/vis Perkin Elmer Instruments at λ = 280 nm. Standard techniques and equipment were used for biological research. The processes of adsorption immobilization of cytotoxic bacterial lectin of B. subtilis IMB B-7724 from physiologic saline on the surface of magnetite and carbon-containing Fe3O4/Al2O3/C NC were studied at room temperature. It has been found that the adsorption capacity of lectin on the surface of magnetite is 25.3 mg/g, and Fe3O4/Al2O3/C NC – 36.3 mg/g (at initial concentrations of lectin 0.06–0.4 mg/mL). The extraction extent of lectin R (%) was 12–38 % for magnetite and 46–67 % for Fe3O4/Al2O3/C NC. The dependence of the adsorption capacity on time was studied. A magnetic fluid (MF) based on single-domain Fe3O4, containing lectin was synthesized and investigated. Immobilization of lectin on MF particles was carried out in a dynamic mode at room temperature for 3 hours. The concentration of lectin in the composition of MF was 0.2 mg/mL. MF with immobilized lectin was further modified with PEG-2000. The synthesis of Fe3O4/ol.Na/lectin/PEG (ol.Na – sodium oleate) vector system was carried out in a dynamic mode for 3 hours. Modification of the surface of nanoparticles with polyethylene glycol was performed in order to increase the stability of the magnetic fluid, reducing the aggregation of particles. To determine the effect of experimental samples on the viability of MCF-7 cells in vitro, the following samples were prepared: Fe3O4/ol.Na/PEG (MF), CFe3O4 = 3 mg/mL; cytotoxic lectin of B. subtilis IMB B-7724 (CL), CCL = 0.2 mg/mL; nanobiocomposite (NBC). Nanobiocomposite based on MF and bacterial lectin was found to have a synergistic cytotoxic effect on MCF-7 human breast cancer cells, causing up to 40 % cell death. The IC50 values for the nanobiocomposite and lectin in relation to MCF-7 cells were 100 and 125 μg/mL, respectively. The results of research show that the combination of properties of lectins and magnetically sensitive iron-containing NC for use in oncology is a promising direction in creating new effective antitumor vector systems for targeted drug delivery and combined local therapy of cancer. The use of natural components in vector systems is a way to minimize the side effects on the body and improve compatibility with other antitumor remedies.

Viscum album : from high dilutions to phytotherapy

Background : Besides conventional anticancer therapy, cancer patients use complementary and alternative medicine like the medicinal herb mistletoe (Viscum album L.), used in oral form or injections.
 For this condition Viscum album (VA) is also used in high dilutions, in injections, as in Brazil.
 
 Aim:
 Our aim is to compare results of basic research about these two presentations: herbal medicine and high dilutions and to look for an eventual continuity of action between the molecular form (herbal medicine) and the informative one (high dilutions)
 
 Method:
 About VA in herbal medicine : a lot of references in immunology, in particular those published by the team of Srini Kaveri and Stephan Baumgartner.(1) (2) (3) (4) (5)
 About VA in high dilutions : the work in immunology of Aloiso Cunha de Carvalho and Leoni Bonamin published in a thesis. (6)
 And then to compare those results with our practice as veterinarian on dogs and cats .
 
 Results : 
 VA in herbal medecine: from basic research results, we know that in low concentration, 
 an immunostimulary action is observed while in higher doses it is a cytotoxic activity.
 These two properties are found in our practical use of VA in dogs or cats : stabilization of the size of tumors for the low concentrations, necrosis of tumors and abscess for the high concentrations. 
 VA in high dilutions (from D3 to D30) : from basic research, an immunostimutating effect is observed. More exactly, on a murin model of tumor of Ehrlich, it is observed an improvement of quality of life, a reduction of the tumor immunosuppressive effect, an enlargement of local inflammations (Oedema) for all concentrations, but only 3D reduces tumor growth, without modifying local necrosis and the immunological parameters.
 In our practice, on two cases of osteosarcoma on dogs, we verify those properties using VA both in herbal medicine and in high dilutions. 
 
 Conclusions:
 From these results, both in basic research and in the practice, we should estimate there is probably a continuity of action fom VA, in High Dynamised Dilutions ( no more molecule), to VA in herbal medicine (molecular activity). From immunostimation to cytotoxicity, from information to molecular activity.
 
 Does each Viscum album’s preparation touch
 the same level of the Immune System ? The same cells ? The same receptors ? A lot of questions remain…
 
 
 References 
 
 
 1) Duong Van Huyen JP and al. Variable sensitivity of lymphoblastoid cells to apoptosis induced by Viscum album Qu FrF, a therapeutic preparation of mistletoe lectin. Chemotherapy. (2001)
 
 2) Duong Van Huyen JP and al. Induction of apoptosis of endothelial cells by Viscum album: a role for anti-tumoral properties of mistletoe lectins. Mol Med. (2002)
 
 3)Duong Van Huyen JP and al Comparative study of the sensitivity of lymphoblastoid and transformed monocytic cell lines to the cytotoxic effects of Viscum album extracts of different origin.. Chemotherapy. (2003)
 
 4) Estko M and al. Tumour cell derived effects on monocyte/macrophage polarization and function and modulatory potential of Viscum album lipophilic extract in vitro.
 BMC Complement Altern Med. 2015
 
 
 5) Saha C, and al Differential Effects of Viscum album Preparations on the Maturation and Activation of Human Dendritic Cells and CD4⁺ T Cell Responses.
 Molecules. 2016 Jul 14;21(7)
 
 6) Aloisio Cunha de Carvalho , ATIVIDADE ANTI-NEOPLÁSICA DE Viscum album (L) EM TUMORES EXPERIMENTAIS: REVISÃO CRÍTICA E ESTUDO EXPERIMENTAL EM TUMOR DE EHRLICH, Thesis Sao Paulo

Assessment of lectinic activity potentials in extracts of some tropical Euphorbiaceace

Lectins bind a variety of cells having cell surface glycoprotein or glycolipid, such as erythrocytes, leukemic cells, yeast and several types of bacteria. Several specificity groups have been identified such as mannose, galactose, N-acetyl glucoseamine, N-acetyl galactoseamine, L-fucose and N-acetyl neuraminic acid. The presence of two or more binding sites for each Lectin molecule allows the agglutination of many cell type. Sixteen (16) species of some tropical Euphorbiaceae plants were assessed for the presence of Lectins. The leaves of Acalypha torta, Acalypha wiskesiana, Acalypha hispida, Codiaeum variegatum, Euphorbia milli, Euphorbia pulcherima, Jatropha curcas and Jatropha gossypifola; the seeds of Croton tiglium, Ricinus comminus and Tetracarpidium conophorum; the stem of Euphorbia tirucalli and the tubers of Manihot esculenta (Cassava, vitamin A variety), Manihot esculenta (cassava, NR 8082 variety), Manihot esculenta (Cassava, TMX 419 variety), Manihot esculenta (Cassava, TMX 4(2) 1425 variety) were used for sourcing the Lectins. A. torta, A. wiskesiana, C. variegatum, C. tiglium, E. milli, E. pulcherima, E. tirucalli, J. curcas, J. gossypifola, R. comminus and T. conophorum agglutinated pooled washed human ABO cells in saline (direct haemagglutination) while A. hispida and the four varieties of M. esculenta showed no agglutination reaction. E. pulcherima showed specificity for B cells only while E. tirucalli showed specificity for O cells only, hence could be rightly indicated by referring to them as anti-B Ep and anti-H Et Lectins respectively (where Ep=Euphorbia pulcherima and Et= Euphorbia tirucalli). However A. torta and T. conophorum cross-reacted with pooled washed ABO cells in differing strengths and when standardized, showed that A. torta at a titre of 16 reacted specifically with O cells and T. conophorum at a titre of 128 reacted specifically with B cells. Based on this, these Lectins could be indicated as anti-H At and anti-B Tc respectively (Where At= Acalypha torta and Tc= Tetracarpidium conophorum). The protein content of the crude extracts of the sixteen (16) species were also assayed using Biuret protein assay method and the results revealed that there are no relation or association between the quantity of protein content and agglutination patterns of the extracts. This research has therefore succeeded in revealing presence of Lectinic properties in extracts of some tropical Euphorbiaceae.