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Infection and Immunity Aug 1978Cell-mediated immunity was evaluated in patients with diabetes mellitus by delayed hypersensitivity skin tests and in vitro lymphocyte transformations. Only 44% of...
Cell-mediated immunity was evaluated in patients with diabetes mellitus by delayed hypersensitivity skin tests and in vitro lymphocyte transformations. Only 44% of diabetic patients had skin test reactivity to Candida antigen, compared with 88% of normal controls (P < 0.001). Insulin-dependent diabetic (IDD) patients had abnormally low lymphocyte transformation responses to phytohemagglutinin, concanavalin A, and streptokinase-streptodornase (P < 0.05). This defect was not corrected by culturing the cells in nondiabetic plasma. IDD patients with persistent hyperglycemia (fasting serum glucose level, >200 mg/dl) had lower levels of transformation than did IDD patients with fasting serum glucose levels less than 150 mg/dl. Lymphocytes from two IDD patients with poor lymphocyte transformation responses had marked improvement in response to phytohemagglutinin when the lymphocytes were cultured after a preincubation period designed to deplete cultures of suppressor activity. Seven IDD patients were studied serially over 12 months. Lymphocyte transformation responses in four of these patients improved coincidentally with a change in the level of fasting hyperglycemia from >200 to <150 mg/dl. The other three IDD patients with consistent fasting serum glucose levels of >200 mg/dl had poor lymphocyte transformation responses. Diabetic patients have demonstrable defects in lymphocyte function which improved in a small number of patients with reduction in the level of fasting hyperglycemia.
Topics: Adolescent; Adult; Aged; Cells, Cultured; Concanavalin A; Diabetes Mellitus; Female; Humans; Immunity, Cellular; Insulin; Longitudinal Studies; Lymphocyte Activation; Male; Michigan; Middle Aged; Phytohemagglutinins; Skin Tests; Streptodornase and Streptokinase; T-Lymphocytes
PubMed: 308493
DOI: 10.1128/iai.21.2.425-429.1978 -
The Plant Journal : For Cell and... Sep 1995Mutations in Vp1 and ABl3 genes of maize and Arabidopsis lead to drastic reductions in the synthesis of a subset of maturation-specific products including seed storage... (Comparative Study)
Comparative Study
Mutations in Vp1 and ABl3 genes of maize and Arabidopsis lead to drastic reductions in the synthesis of a subset of maturation-specific products including seed storage proteins. Gene Phaseolus vulgaris ABl3-like factor (PvAlf), whose protein product is similar to the ABl3 and Vp1 proteins, has been cloned. Here, it is shown that PvAlf positively regulates phaseolin and phytohemagglutinin (PHA-L) promoters in particle bombardment assays. PvAlf mRNA expression is embryo-specific and temporally complex. PvAlf mRNA abundance is highest during two periods (9-14 and 22-35 days after flowering) that precede the onsets of seed maturation and seed abscission, respectively. Protein fusions with the DNA-binding domain of the yeast transcriptional activator GAL4 demonstrated that the N-terminal 243 amino acids of PvAlf function as a strong transcriptional activation domain in yeast (Saccharomyces cerevisiae) and plant cells. This domain consists of a central cluster rich in serine, threonine and proline (STP cluster) flanked by two negatively charged regions containing bulky hydrophobic residues similar to acidic activation domains of Vp1, the herpes simplex virus virion protein VP16 and transcription factors GCN4 and HAP4 from yeast. Together with the Vp1 proteins of maize and rice and ABl3, PvAlf constitutes a class (Vp1/ABl3-like factors or VAlfs) of regulatory factors that are pivotal for the promotion of seed maturation and dormancy in angiosperms.
Topics: Amino Acid Sequence; Arabidopsis; Base Sequence; Cotyledon; DNA Primers; Fabaceae; Gene Expression; Gene Expression Regulation, Plant; Genes, Plant; Molecular Sequence Data; Phytohemagglutinins; Plant Lectins; Plant Proteins; Plants, Medicinal; Polymerase Chain Reaction; Promoter Regions, Genetic; RNA, Messenger; Restriction Mapping; Sequence Homology, Amino Acid; TATA Box; Toxins, Biological; Trans-Activators; Zea mays
PubMed: 7550372
DOI: 10.1046/j.1365-313x.1995.08030331.x -
Proceedings of the National Academy of... Jul 1985Three cDNA clones isolated from Syrian hamster cells (p4F1, p2F1, and p2A9) contain sequences that are preferentially expressed in the G1 phase of the cell cycle. The...
Three cDNA clones isolated from Syrian hamster cells (p4F1, p2F1, and p2A9) contain sequences that are preferentially expressed in the G1 phase of the cell cycle. The expression of these sequences was investigated in human peripheral blood cells from normal individuals and from patients with leukemia. The expression of p4F1 and p2F1 is clearly dependent on the cell cycle in peripheral blood mononuclear cells stimulated to proliferate with phytohemagglutinin; the p2A9 sequences cannot be clearly detected in human lymphocytes but are expressed in a cell-cycle-dependent manner in human diploid fibroblasts (WI-38). These genes also show different levels of expression in lymphoid and myeloid leukemias. The highest level of expression for p2A9 is found in patients with chronic myelogenous leukemia, and the lowest in patients with chronic lymphocytic leukemia. For p2F1 and p4F1, the highest levels of expression are found in chronic and acute myelogenous leukemia. At least two other cell-cycle genes are not expressed at detectable levels in human leukemias. These findings suggest that the activation of cell-division-cycle genes might contribute, like cellular oncogenes, to the phenotype of human malignancies and that, perhaps, new oncogenes could be found by identifying and isolating genes whose expression is dependent on the cell cycle.
Topics: Cell Cycle; Fibroblasts; Gene Expression Regulation; Humans; Leukemia; Lymphocyte Activation; Lymphocytes; Oncogenes; Phytohemagglutinins
PubMed: 3859871
DOI: 10.1073/pnas.82.13.4463 -
The Journal of Comparative Neurology Jun 2012The connections of the lateral hypothalamic area juxtadorsomedial region (LHAjd) were investigated in a series of pathway-tracing experiments involving iontophoretic...
The connections of the lateral hypothalamic area juxtadorsomedial region (LHAjd) were investigated in a series of pathway-tracing experiments involving iontophoretic co-injection of the tracers Phaseolus vulgaris-leucoagglutinin (PHA-L; for outputs) and cholera toxin B subunit (CTB; for inputs). Results revealed that the LHAjd has connections with some 318 distinct gray matter regions encompassing all four subsystems-motor, sensory, cognitive, and behavioral state-included in a basic structure-function network model of the nervous system. Integration of these subsystems is necessary for the coordination and control of emotion and behavior, and in that regard the connections of the LHAjd indicate that it may have a prominent role. Furthermore, the LHAjd connections, together with the connections of other LHA differentiations studied similarly to date, indicate a distinct topographic organization that suggests each LHA differentiation has specifically differing degrees of involvement in the control of multiple behaviors. For the LHAjd, its involvement to a high degree in the control of defensive behavior, and to a lesser degree in the control of other behaviors, including ingestive and reproductive, is suggested. Moreover, the connections of the LHAjd suggest that its possible role in the control of these behaviors may be very broad in scope because they involve the somatic, neuroendocrine, and autonomic divisions of the nervous system. In addition, we suggest that connections between LHA differentiations may provide, at the level of the hypothalamus, a neuronal substrate for the coordinated control of multiple themes in the behavioral repertoire.
Topics: Animals; Brain Mapping; Cholera Toxin; Hypothalamic Area, Lateral; Iontophoresis; Male; Neural Pathways; Neurons; Phytohemagglutinins; Rats; Rats, Sprague-Dawley
PubMed: 22488503
DOI: 10.1002/cne.23064 -
Archives of Disease in Childhood May 1981Antibody-dependent, phytohaemagglutinin-induced, and spontaneous cytotoxicity was studied in 44 term and 60 preterm newborn babies, all of whom were healthy and of...
Antibody-dependent, phytohaemagglutinin-induced, and spontaneous cytotoxicity was studied in 44 term and 60 preterm newborn babies, all of whom were healthy and of normal weight for gestational age. Twenty-seven adults were used as controls. Antibody-dependent cytotoxicity was low in term babies particularly in the preterm ones during the first 4 days of life, but soon rose to adult levels. Phytohaemagglutinin-induced cytotoxicity was low both in term and preterm babies compared with adult levels, and remained lower throughout the neonatal period although it began to rise. Spontaneous cytotoxicity was lower in preterm babies than in term ones during the first 2 weeks of life, and lower too than in adults. These findings indicate decreased cytotoxic ability of neonatal leucocytes especially during the first 4 days of postnatal life particularly in preterm babies, suggesting either lack of effector cells or that the cells are functionally immature.
Topics: Antibody-Dependent Cell Cytotoxicity; Cells, Cultured; Cytotoxicity, Immunologic; Humans; Infant, Newborn; Infant, Premature; Lymphocytes; Phytohemagglutinins
PubMed: 7259259
DOI: 10.1136/adc.56.5.377 -
The Journal of Biological Chemistry Sep 1987The structural determinants required for interaction of oligosaccharides with leukoagglutinating phytohemagglutinin (L-PHA) and erythroagglutinating phytohemagglutinin...
Oligosaccharide specificities of Phaseolus vulgaris leukoagglutinating and erythroagglutinating phytohemagglutinins. Interactions with N-glycanase-released oligosaccharides.
The structural determinants required for interaction of oligosaccharides with leukoagglutinating phytohemagglutinin (L-PHA) and erythroagglutinating phytohemagglutinin (E-PHA) from Phaseolus vulgaris have been studied by immobilized lectin affinity chromatography. Homogeneous oligosaccharides of known structure, purified following release from Asn with N-glycanase and reduction with NaBH4, were tested for their ability to interact with columns of L- and E-PHA-agarose. The characteristic elution position obtained for each oligosaccharide was reproducible and correlated with specific structural features. In virtually all cases, L- and E-PHA yielded identical results, indicating that their specificities for reduced oligosaccharides are similar. Both lectins retarded oligosaccharides bearing alpha 2,3- but not alpha 2,6-linked sialic acid. Desialylated oligosaccharides containing one, two, three, or four peripheral N-acetyllactosamine-type branches were retarded to varying extents by both lectins; however, this interaction was decreased or eliminated by removal of Gal. Desialylated oligosaccharides containing a bisecting GlcNAc residue attached to the beta-linked core Man displayed the greatest interaction with both lectins. Structures containing terminal sulfate or GalNAc did not interact with either lectin. In some instances, the specificities of L- and E-PHA lectins for free, reduced oligosaccharides differed from those established using glycopeptides. Therefore, the structural requirements for interaction with lectins such as L- and E-PHA must be fully and systematically defined using the appropriate authentic standards in order to use lectin affinity chromatography for the fractionation and characterization of free oligosaccharides.
Topics: Chromatography, Affinity; Fabaceae; Glycoside Hydrolases; Hemagglutination; Oligosaccharides; Phytohemagglutinins; Plant Lectins; Plants, Medicinal
PubMed: 3624245
DOI: No ID Found -
American Journal of Human Genetics Jul 1985Although it is clear that the major histocompatibility complex is associated with lymphocyte glucocorticoid sensitivity in mice, there has been less evidence for a...
Although it is clear that the major histocompatibility complex is associated with lymphocyte glucocorticoid sensitivity in mice, there has been less evidence for a similar relationship in man. We have typed 158 individuals for: (1) 13 A locus and 16 B locus antigens, (2) degree of stimulation of their purified lymphocytes by phytohemagglutinin A (PHA), and (3) degree of inhibition of the PHA stimulation by prednisolone and prednisolone-21-hemisuccinate. In contrasts of individuals with a particular antigen (homozygous or heterozygous) with all remaining individuals, HLA-B7 was found to be associated with an enhancing effect on the log stimulation by PHA while other antigens of these series did not have significant associations. In similar contrasts, A10 was associated with a decrease in sensitivity to glucocorticoid inhibition of PHA stimulation as measured by the log I50 of the suppression of PHA stimulation. Other antigens of these series were not found to have significant associations with the glucocorticoid sensitivity of lymphocytes in this assay.
Topics: Adolescent; Adult; Child; Child, Preschool; Female; Genes, MHC Class I; HLA Antigens; Humans; Lymphocyte Activation; Male; Middle Aged; Phytohemagglutinins; Prednisolone
PubMed: 9556664
DOI: No ID Found -
Iranian Journal of Allergy, Asthma, and... Aug 2022A decrease in T cell count or reduced T cell function can be indicative of T cell immunodeficiency. In the present study, T-cell function was assessed using...
A decrease in T cell count or reduced T cell function can be indicative of T cell immunodeficiency. In the present study, T-cell function was assessed using Carboxyfluorescein diacetate succinimidyl ester (CFSE) dilution test after stimulation with commonly used Phytohaemagglutinin (PHA) or anti-CD3/anti-CD28 coated beads in pediatric patients with recurrent infections. Seven infants with recurrent infections and seven sex/age-matched healthy infants were included in this study. A blood cell count, immunophenotyping, and serum immunoglobulin level were performed. The proliferation of T cells was also assessed with CFSE dilution after stimulation with PHA or anti-CD3/anti-CD28 coated beads. This study showed increased IgA, IgG, and IgM levels in patients compared to the controls. In contrast to the controls, the immunophenotyping results showed a significant decline in the number of CD4+ T cells in patients. Although there was no difference in CD3+ T cell proliferation between patients and controls, the CD4+ and CD8+ T cell proliferation rates were significantly decreased in patients when stimulated with PHA. As a mitogen with the potential for maximum proliferation of T cells, PHA is better able to distinguish between patients with recurrent infections and controls than anti-CD3/anti-CD28, which mimics only the TCR pathway for stimulation of T cells.
Topics: CD28 Antigens; Cell Proliferation; Child; Fluoresceins; Humans; Immunoglobulin A; Immunoglobulin G; Immunoglobulin M; Infant; Lymphocyte Activation; Mitogens; Phytohemagglutinins; Receptors, Antigen, T-Cell; Reinfection; Succinimides
PubMed: 36243934
DOI: 10.18502/ijaai.v21i4.10293 -
Scientific Reports Mar 2016Glycans normally exist as a dynamic equilibrium of several conformations. A fundamental question concerns how such molecules bind lectins despite disadvantageous...
Glycans normally exist as a dynamic equilibrium of several conformations. A fundamental question concerns how such molecules bind lectins despite disadvantageous entropic loss upon binding. Bisected glycan, a glycan possessing bisecting N-acetylglucosamine (GlcNAc), is potentially a good model for investigating conformational dynamics and glycan-lectin interactions, owing to the unique ability of this sugar residue to alter conformer populations and thus modulate the biological activities. Here we analyzed bisected glycan in complex with two unrelated lectins, Calsepa and PHA-E. The crystal structures of the two complexes show a conspicuous flipped back glycan structure (designated 'back-fold' conformation), and solution NMR analysis also provides evidence of 'back-fold' glycan structure. Indeed, statistical conformational analysis of available bisected and non-bisected glycan structures suggests that bisecting GlcNAc restricts the conformations of branched structures. Restriction of glycan flexibility by certain sugar residues may be more common than previously thought and impinges on the mechanism of glycoform-dependent biological functions.
Topics: Acetylglucosamine; Animals; Binding, Competitive; Brain; Carbohydrate Conformation; Carbohydrate Sequence; Cell Membrane; Crystallography, X-Ray; Electrophoresis, Polyacrylamide Gel; Magnetic Resonance Spectroscopy; Male; Mice, Knockout; Models, Molecular; N-Acetylglucosaminyltransferases; Phytohemagglutinins; Plant Lectins; Polysaccharides; Protein Binding; Protein Domains
PubMed: 26971576
DOI: 10.1038/srep22973 -
British Journal of Cancer Aug 1999Lectin binding specificities for carbohydrate allow phenotypic and functional characterization of membrane-associated glycoproteins expressed on cancer cells. This...
Lectin binding specificities for carbohydrate allow phenotypic and functional characterization of membrane-associated glycoproteins expressed on cancer cells. This analysis examined wheatgerm agglutinin binding to pancreatic cancer cells in vitro and the resulting toxicity. Membrane preparations of nine human pancreatic carcinoma cell lines were studied for lectin binding using wheatgerm agglutinin (WGA), concanavalin A (ConA) and phytohaemagglutinin-L (PHA-L) in a lectin blot analysis. Cell proliferation in vitro was measured by thymidine incorporation in the absence or presence of lectins at various concentrations. Sialic acid binding lectins or succinyl-WGA (succWGA) served as controls. WGA toxicity was tested after swainsonine or neuraminidase pretreatment. Binding and uptake of fluorescein-labelled lectins was studied under fluorescence microscopy. All pancreatic cell lines displayed high WGA membrane binding, primarily to sialic acid residues. Other lectins were bound with weak to moderate intensity only. Lectin toxicity corresponded to membrane binding intensity, and was profound in case of WGA (ID50 at 2.5-5 microg ml(-1)). WGA exposure induced chromatin condensation, nuclear fragmentation and DNA release consistent with apoptosis. Important steps for WGA toxicity included binding to sialic acid on swainsonine-sensitive carbohydrate and lectin internalization. There was rapid cellular uptake and subsequent nuclear relocalization of WGA. In contradistinction to the other lectins studied, WGA proved highly toxic to human pancreatic carcinoma cells in vitro. WGA binding to sialic acid residues of N-linked carbohydrate, cellular uptake and subsequent affinity to N-acetyl glucosamine appear to be necessary steps. Further analysis of this mechanism of profound toxicity may provide insight relevant to the treatment of pancreatic cancer.
Topics: Antineoplastic Agents; Cell Division; Cell Membrane; Cell Survival; Chromatin; Humans; Kinetics; N-Acetylneuraminic Acid; Neuraminidase; Pancreatic Neoplasms; Phytohemagglutinins; Tumor Cells, Cultured; Wheat Germ Agglutinins
PubMed: 10468292
DOI: 10.1038/sj.bjc.6690593