Lectins are glycoproteins that specifically bind carbohydrate structures and may participate in the biodefense mechanisms of fish. In this study, the binding of three lectins, Dolichos biflorus agglutinin (DBA), soybean agglutinin (SBA), Bandeiraea simplicifolia BS-1 (isolectin B4), Triticum vulgaris (WGA), Arachis hypogaea (PNA) and Ulex europaeus (UEA-I) were studied in the gill, liver, intestine, kidney, heart, and spleen of the flat fish Paralichthys olivaceus. DBA was detected in intestinal mucous cells, as well as in gill epithelial and mucous cells. It was weakly detected in renal tubule epithelial cells and in bile duct epithelial cells. The strong SBA staining was seen in the intestinal club cells, in bile duct epithelial cells and renal tubule epithelial cells. There were intense positive reactions for isolectin B4 in gill epithelial and mucous cells, and the strong isolectin B4 staining was seen in epithelial cells of the bile duct and intestine. The strong WGA staining was seen in the gill mucosal cells, sinusoid, renal tubule epithelial cells and mucosal cells of the intestine. UEA-I was detected in the gill epithelial and mucosal cells, bile duct epithelial cells and renal tubular epithelial cells. These results suggest that the six lectins examined were localized in the covering epithelia of the various organs of the flat fish and they may participate in the biodefense mechanism of the intra body surface in which is exposed to various antigens.
Animals ; Epithelial Cells/metabolism ; Flatfishes/*metabolism ; Histocytochemistry/veterinary ; Lectins/*metabolism ; Mucus/metabolism ; Peanut Agglutinin/metabolism ; Plant Lectins/metabolism ; Soybean Proteins/metabolism ; Wheat Germ Agglutinins/metabolism

OBJECTIVETo obtain peptides binding specifically to Pisum sativum agglutinin (PSA) from a phage-displayed random peptide library.

METHODS(1) A phage-displayed random hexapeptide library was screened with PSA as target. (2) Dot blot was used to analyze the influence of the alpha-Met-D-mannoside on binding between PSA and phage-displayed peptides. (3) Three peptides (RMWSF, RYDYSY, LRLRQL) were selectively synthesized, and different concentrations were used to inhibit PSA and ConA binding to the HRP.

RESULTSThe enrichment occurred obviously after three rounds of screening. The insert sequences of amino acids, displayed on 22 phage DNAs from the third round of screening, were divided into three groups. The binding of phage-displayed peptides to PSA was specific as shown by dot blot and could be inhibited by alpha-Met-D-mannoside. LRLRQL was not dissolved in water. ARMWSF and RYDYSY inhibited binding of PSA to HRP, but failed to inhibit binding ConA to HRP.

CONCLUSIONThe binding site of peptides ARMWSF and RYDYSY is different to that of alpha-Met-D-mannoside.

Binding Sites ; Peptide Library ; Peptides ; metabolism ; Plant Lectins ; metabolism ; Protein Binding ; Recombinant Proteins ; metabolism

OBJECTIVETo explore the significance of Lens culinaris-reactive alpha-Fetoprotein (AFP-L3) detection in primary hepatocellular carcinoma.

METHODSAFP-L3 was isolated by using microspin column coupled with lens culinaris agglutinin (LCA), AFP and AFP-L3 were detected with chemiluminescent immunoassay, the proportion of AFP L3 levels were calculated, and the relationship between the elevated AFP-L3 (%) levels and benign and malignant liver disease was analyzed.

RESULTSThere were significant differences in positive rate between the patients of HCC, suspected HCC and other liver disease (81.80%, 73.68%, 11.80%, respectively, P < 0.05). Among the undetermined HCC (suspected HCC, liver disease) patients, 12 out of 21 cases of AFP-13 positive were diagnosed to be HCC within 6 months, and 6 of them were diagnosed to be the single small HCC at the early stage through B-Ultrasonic Diagnosis or CT. Among 62 cases of AFP-L3 negative, 3 cases were diagnosed to be HCC within 6 months and the risk of occurrence of HCC for AFP-L3 positive increased 11.9 times.

CONCLUSIONAFP-L3 has no correlation with AFP value, and it can be used as an independent HCC diagnosis factor. The detection of AFP-L3 has a significant implication for the identification of benign or malignant liver disease and the early stage predictive diagnosis of HCC while AFP increases.

Adult ; Aged ; Biomarkers, Tumor ; metabolism ; Carcinoma, Hepatocellular ; diagnosis ; pathology ; Female ; Humans ; Lens Plant ; chemistry ; metabolism ; Male ; Middle Aged ; Neoplasm Invasiveness ; Plant Lectins ; analysis ; Young Adult ; alpha-Fetoproteins ; analysis

OBJECTIVETo explore the mechanism of Flt3 receptor-interacting lectin (FRIL) maintains quiescence of hematopoietic stem cells (HSCs) in vitro.

METHODSCord blood CD34+ cells were cultured in suspension medium supplemented with or without FRIL and FL. Cells were collected at different time points and the expression of some cell cycle regulators, especially those involved in G0/G1 phase regulation were detected on mRNA and protein level.

RESULTSThe expressions of G0/G1 phase related cyclins or CDKs were undetectable in the newly isolated CD34+ cells, expressions of Cyclin D3, CDK6 and P27 were the lowest in FRIL cultured group after 3d's culture (FRIL group: 483 +/- 63, 553 +/- 39, 0.312 +/- 0.030; FL group: 2437 +/- 52, 3209 +/- 98, 0.787 +/- 0.024; BLANK: 914 +/- 105, 1497 +/- 55, 0.616 +/- 0.029, respectively), but the expression of P53 was the highest in FRIL group (FRIL group: 4.476 +/- 0.159; FL group: 0.581 +/- 0.099, BLANK: 2.167 +/- 0.114). The expression of positive regulators of cell cycle in FRIL group were the same as that of FL group and blank group or lower.

CONCLUSIONFRIL preserves HSCs effectively in vitro through the mechanisms of down-regulation of cyclin D3 and CDK6 and activation of P53. P27 is mostly involved in the differentiation of HSCs.

Antigens, CD34 ; Cell Cycle ; drug effects ; Cell Cycle Proteins ; genetics ; metabolism ; Cells, Cultured ; Fetal Blood ; cytology ; Hematopoietic Stem Cells ; cytology ; drug effects ; metabolism ; Humans ; Mannose-Binding Lectins ; pharmacology ; Plant Lectins ; pharmacology ; RNA, Messenger ; genetics

Using total DNA isolated from Amaranthus caudatus as the template, a DNA fragment of about 700bp upstream of the coding sequence of Amaranthus caudatus agglutinin (ACA) gene was amplified by TAIL-PCR and cloned. To examine the regulatory function of this DNA fragment, it was inserted into a plant expression vector containing GUS gene to substitute the CaMV 35S promoter and the resulted recombinant plasmid was designated as pBpAG. The expression vector pBpAG was transferred to different tissues of plants, via Agrobacterium-mediated transformation in vacuum condition. Transient expression of GUS in the transformed tissues was detected by histochemical GUS staining and the results showed that the GUS activity was expressed specifically in seeds. These preliminary results indicate that this DNA fragment upstream of the ACA coding sequence could very possibly be a promoter with seed specificity. Some putative cis-elements within the promoter were discussed.
Amaranthus ; genetics ; Base Sequence ; Cloning, Molecular ; Escherichia coli ; genetics ; metabolism ; Molecular Sequence Data ; Plant Lectins ; genetics ; Promoter Regions, Genetic ; genetics ; Rhizobium ; genetics ; metabolism

Ex vivo maintainance of human stem cells is crucial for many clinical applications. Current culture conditions provide some level support but cytokines induce most quiescent stem cells to proliferate and differentiate. Better control of primitive cells is needed to extend the time and range of manipulation of such cells. A recently identified plant lectin Flt3 receptor-interacting lectin (FRIL) present may a special ability to preserve primitive CB progenitors for extended periods in culture without exogenous cytokines. But the mechanisms of FRIL preserving quiescent primitive cells are still unknown. Recently a novel protein HTm4 and its alternatively spliced variant HTm4S, which serve as hematopoietic cell cycle regulators, have been identified. In this report we studied the effect of FRIL on the in vitro maintenance of quiescent human cord blood stem cells and the expression of the novel hematopoietic cell cycle regulator HTm4 and HTm4S in progenitor cells cultured in FRIL. We analyzed the proliferation and the HPP-CFC proportion of CD34(+) cells treated with FRIL. The human HTm4 and HTm4S mRNA expression was detected by semi-quantitative RT-PCR, and the cell cycle status of CB CD34(+) cells was analyzed by FACS. The results showed that incubation of CD34(+) cells in FRIL resulted in a low proliferation of progenitor cells and fewer cycling cells, but FRIL selectively maintained a higher number of primitive cells with proliferative potential in suspension culture. CB CD34(+) cells cultured in FRIL showed significant diversity in the expression of HTm4 and HTm4S during 0~14 d. On d 0, HTm4 was detected at high level, downregulated on d 1, but upregulated during d 3 to d 14, and reaching the highest level on d 7. But the expression levels of HTm4S changed little in the cells cultured in FRIL except the obviously increased expression on d 7. Exogenous expression showed that HTm4 was localized around the karyon while HTm4S scatted in the cytoplasm, respectively, which may be responsible for their difference in function. Thus, FRIL can preserve quiescent primitive CD34(+), and FRIL's ability to preserve quiescent primitive cells in a reversible manner may significantly expand the time and range of ex vivo manipulations of human stem cells for clinical applications. In other words, HTm4 and HTm4S may play a crucial role in the cell cycle modulation of CD34(+) progenitor cells maintained with FRIL in vitro.
Antigens, CD20 ; biosynthesis ; genetics ; Antigens, CD34 ; metabolism ; Cell Cycle ; Cell Cycle Proteins ; biosynthesis ; genetics ; Cell Separation ; Cells, Cultured ; Fetal Blood ; cytology ; Hematopoietic Stem Cells ; cytology ; Humans ; Mannose-Binding Lectins ; pharmacology ; Membrane Proteins ; biosynthesis ; genetics ; Plant Lectins ; pharmacology

OBJECTIVE: To detect the expression of galectin-3 (gal-3) and Sambucus nigra agglutinin (SNA) and determine their clinicopathological significance in breast cancers and benign breast lesions. METHODS: Envison immunohistochemistry for staining gal-3 expression, and ABC affinity-cytochemistry to detect SNA expression were used in paraffin-embedded slides from specimens of breast cancers (n=60) and benign lesions (n=30). RESULTS: The positive rates and scoring means of gal-3 and SNA were significantly higher in breast cancer (48.3%, 2.07 +/- 2.25, 2.12 +/- 2.26) than those in benign lesions (26.7%, 1.03 +/- 1.63, 1.07 +/- 1.59, P < 0.05). The scoring means of gal-3 and SNA expression were significantly lower in the positive cases of estrogen receptor (ER) and the negative ones of CA15-3 than those in the negative cases and the positive ones (P < 0.05).The survival analysis of Kaplan-Meier showed the 5-year survival rate and mean survival period were significantly lower in the gal-3 or SNA expression positive cases than those in the negative cases of breast cancer (P<0.01). CONCLUSION The expressive level of gal-3 and SNA lectins might have important effect on the carcinogenesis, progression and biologic behaviors of breast cancer. The positive cases of gal-3 and /or SNA expression might have poor prognosis.
Adolescent ; Adult ; Aged ; Breast Neoplasms ; metabolism ; pathology ; Female ; Fibrocystic Breast Disease ; metabolism ; pathology ; Galectin 3 ; genetics ; metabolism ; Humans ; Middle Aged ; Mucin-1 ; metabolism ; Plant Lectins ; genetics ; metabolism ; Prognosis ; Receptors, Estrogen ; metabolism ; Ribosome Inactivating Proteins ; genetics ; metabolism ; Young Adult

In this study, wheat germ agglutinin (WGA), tomato lectin (TL) and asparagus pea lectin (AL) were covalently coupled to conventional poly lactic-co-glycolic acid (PLGA) nanoparticles using a carbodiimide method to take the bioadhesive properties. The influences of the amounts of activating agents and lectins, as well as the activating time and incubating time on the effect of lectin conjugating were investigated to optimize the preparation conditions. The mean diameters of the performed nanoparticles with or without lectin conjugation ranged from (140.7 +/- 5.7) nm to (245.6 +/- 18.3) nm. The yields of lectin conjugating and the lectin surface concentrations on nanoparticles were determined by Lowry's methods, and were calculated to be (18.97 +/- 2.9)% - (20.15 +/- 2.4)% and (9.46 +/- 1.45)--(10.05 +/- 1.19) microg x mg(-1), respectively. The in vitro bioadhesive activities of nanoparticles were evaluated by pig gastric mucin (PM) binding experiments. After incubation at room temperature for 60 min, the equilibria of binding between nanoparticles and PM reached. The percentages of the bulk PM which had interacted with different lectin-conjugated PLGA nanoparticles were 15.5%, 12.1% and 11.8%, respectively. The conjugation of lectin enhanced the interaction about 2.4 - 3.2 fold compared with that of the non-conjugated one. A mathematical model was used based on the Langmuir equation, and the rate constants of interaction (k) were calculated to be 2.373 x 10(-3), 1.536 x 10(-3) and 1.714 x 10(-3) (microg x min/mL)(-1), respectively. These interactions could be competitively inhibited by their corresponding sugars of lectins. The results suggested that lectin-conjugated PLGA nanoparticles greatly promoted the interaction with PM in vitro compared with the conventional PLGA nanoparticles, thus would improve the bioadhesion on gastrointestinal mucosa after oral administration resulting in a prolonged residence time in the gastrointestinal tract.
Adhesiveness ; Drug Carriers ; Drug Compounding ; Drug Delivery Systems ; Gastric Mucins ; metabolism ; Lactic Acid ; chemistry ; metabolism ; Nanoparticles ; Plant Lectins ; chemistry ; metabolism ; Polyglycolic Acid ; chemistry ; metabolism ; Protein Binding ; Wheat Germ Agglutinins ; chemistry ; metabolism

OBJECTIVETo study the expressive levels of galectin-3(gal-3) and Sambucus nigra agglutinin(SNA) and their clinicopathological significance in the benign and malignant lesions of stomach.

METHODSEnVision immunohistochemistry for assaying gal-3 expressive level and ABC cytochemistry for determining SNA expressive level were used in conventional paraffin-embedded sections from specimens of gastric cancer(n=49), peritumoral tissues(n=20), metastatic foci of lymph nodes(n=36), and different types of benign lesions(n=80).

RESULTSThe positive rates of gal-3 and SNA were significantly higher in gastric cancer tissues than those in peritumoral tissues and different types of benign lesions(P<0.05, P<0.01). The positive cases of gal-3 and/or SNA in peritumoral tissues and benign lesions showed mild- to severe-atypical hyperplasia of mucous epithelial cells. No difference was found between the primary foci and metastatic foci in gal-3 and SNA expressions(P>0.05). The positive rates of gal-3 and SNA were significantly lower in histologic grade II(, infiltrating depth T1,T2 and no-metastasis of regional lymph node than those in histologic grade III(,IIII(, infiltrating depth T3,T4 and metastasis of lymph node in gastric cancer(P<0.05). The positive rates of gal-3 and SNA were higher in lymphnode metastatic site N1 and no-metastasis of distant organs than those in lymphnode metastatic site N2,N3 and metastasis of distant organs, but no significant difference was found(P>0.05). The consistency was found between the expression of gal-3 and SNA in gastric cancer tissues(chi(2)=6.59,P<0.05).

CONCLUSIONSThe expressive levels of gal-3 and SNA may be important molecular markers of lectins for reflecting the carcinogenesis, progression and biological behaviors in gastric cancer.

Adenoma ; pathology ; Adult ; Aged ; Female ; Galectin 3 ; metabolism ; Gastritis ; pathology ; Humans ; Immunohistochemistry ; Lymphatic Metastasis ; Male ; Middle Aged ; Neoplasm Staging ; Plant Lectins ; metabolism ; Polyps ; pathology ; Ribosome Inactivating Proteins ; metabolism ; Stomach Neoplasms ; metabolism ; pathology

Reports of influenza A virus infections in dogs has received considerable attention from veterinarians, virologists, and epidemiologists. Interaction between influenza viral hemagglutinin and cell oligosaccharides containing sialic acid residues results in infection. Sialic acids have an alpha-2,3-linkage to the penultimate galactose in the avian influenza virus receptor and an alpha-2,6-linkage in the human receptor. To date, there are no detailed data on the tissue distribution or histological features of either type of sialic acid-linked influenza virus receptors in beagle dogs, which are common laboratory animals and pets. We conducted the current study to visualize the in situ tissue distribution of both sialic acid-linked influenza virus receptors in various organs of beagle dogs using Maackia amurensis lectin II and Sambucus nigra agglutinin. Both alpha-2,3- and alpha-2,6-sialic acid-linked receptors were detected in the endothelial cells of the respiratory tract and other organs. Endothelial cells of most gastrointestinal organs were negative for alpha-2,3-sialic acid-linked receptors in the dogs. Our results suggested that these canine organs may be affected by influenza virus infection. The findings from our study will also help evaluate the occurrence and development of influenza virus infections in dogs.
Animals ; Dog Diseases/metabolism ; Dogs/metabolism/*virology ; Female ; Influenza A Virus, H5N1 Subtype/*metabolism ; Maackia/chemistry ; Male ; N-Acetylneuraminic Acid/metabolism ; Organ Specificity ; Orthomyxoviridae Infections/metabolism/transmission/veterinary ; Plant Lectins/metabolism ; Receptors, Cell Surface/analysis/chemistry/metabolism ; Receptors, Virus/analysis/chemistry/*metabolism ; Sambucus nigra/chemistry