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1.
Respir Res ; 22(1): 165, 2021 Jun 01.
Article in English | MEDLINE | ID: mdl-34074288

ABSTRACT

BACKGROUND: The positive rate of pathogenic examination about tuberculosis is low. It is still difficult to achieve early diagnosis for some TB patients. The value of Interferon-gamma release assays (IGRA) in the diagnosis of active tuberculosis remains controversial. The purpose of this multicenter prospective study was to verify and validate the role of TBAg/PHA ratio (TB-specific antigen to phytohaemagglutinin) of T-SPOT.TB assay in diagnosing ATB. METHODS: We prospectively enrolled 2390 suspected pulmonary tuberculosis patients with positive T-SPOT assay results from three tertiary hospitals. RESULTS: A total of 1549 ATB (active tuberculosis) patients (including 1091 confirmed and 458 probable ATB) and 724 non-tuberculosis (non-TB) patients with positive T-SPOT results were included. The results of this study showed that ESAT-6 and CFP-10 in the T-SPOT.TB assay were significantly higher in the ATB group compared with the non-TB group, while PHA was lower in the ATB group. Results of ESAT-6, CFP-10 and PHA show a certain diagnostic performance, but moderate sensitivity and specificity. The TBAg/PHA ratio, a further calculation of ESAT-6, CFP-10 and PHA in T-SPOT.TB assay showed improved performance in the diagnosis of active Tuberculosis. If using the threshold value of 0.2004, the specificity and sensitivity of TBAg/PHA ratio in distinguishing ATB from non-TB were 92.3% and 74.4%, PPV was 95.4, PLR was 9.6. CONCLUSION: By recalculating the results of T-SPOT.TB Assay, the TBAg/PHA ratio shows high prospect value in the diagnosis of active tuberculosis in high prediction areas.


Subject(s)
Antigens, Bacterial/metabolism , Mycobacterium tuberculosis/immunology , Phytohemagglutinins/metabolism , Tuberculosis, Pulmonary/diagnosis , Antigens, Bacterial/immunology , Bronchoalveolar Lavage Fluid/microbiology , Female , Follow-Up Studies , Humans , Male , Middle Aged , Mycobacterium tuberculosis/isolation & purification , Prospective Studies , Reproducibility of Results , Sputum/metabolism , Sputum/microbiology , Tuberculosis, Pulmonary/metabolism , Tuberculosis, Pulmonary/microbiology
2.
Biotechnol Lett ; 41(12): 1361-1371, 2019 Dec.
Article in English | MEDLINE | ID: mdl-31631231

ABSTRACT

OBJECTIVE: Although several methods have been reported and used for in vitro T cell amplification, there are no consistent reports on the optimal stimulation conditions and the characterization of these stimulated T cells. The current study aimed to determine the optimal conditions for efficient T cell amplification by two commonly used methods involving CD3/CD28 antibody and phytohemagglutinin (PHA), respectively. RESULTS: Orthogonal design and CCK8 assay showed that 5 µg/mL CD3, 5 µg/mL CD28, and 100 ng/mL IL2 for the first method and 50 µg/mL PHA for the second method was optimal for T cell stimulation. Flow cytometry demonstrated that the percentage of CD8+ in the stimulated groups significantly increased, while the percentage of CD4+/CD8+ was significantly decreased compared with the unstimulated group. The percentage of CD4+ showed no significant difference among the three groups. Notably, there was no significant difference between the two stimulated groups. In addition, the percentage of apoptotic cells was significantly increased in the stimulated groups compared with the unstimulated group, but showed no remarkable difference between the PHA and CD3/CD28 stimulation groups. Glycolysis analysis showed that the glycolytic capacity and glycolytic reserve were both significantly increased in the PHA and CD3/CD28 groups compared with the unstimulated group, with no significant difference noted between the stimulated groups. CONCLUSIONS: Although both stimulation methods showed similar efficacies, we suggest the PHA method might be better considering its easy application and cost-effective nature.


Subject(s)
Cell Proliferation/drug effects , Cytological Techniques/methods , Lymphocyte Activation/drug effects , T-Lymphocytes/immunology , Antibodies/metabolism , CD28 Antigens/metabolism , CD3 Complex/metabolism , Cells, Cultured , Flow Cytometry , Healthy Volunteers , Humans , Phytohemagglutinins/metabolism , T-Lymphocytes/drug effects
3.
Biomarkers ; 23(2): 188-195, 2018 Mar.
Article in English | MEDLINE | ID: mdl-29130773

ABSTRACT

BACKGROUND: Oral lichen planus (OLP) is one of the most common oral mucosal lesions affecting 0.5-2% of the adult population. It is difficult to distinguish between OLP and other oral mucosal diseases. Structural changes in the glycans of saliva proteins might be reliable indicators of OLP. However, little is known about the alteration of salivary glycopatterns during OLP. OBJECTIVE: We aimed to investigate the alterations of salivary protein glycosylation related to OLP. MATERIAL AND METHODS: Twenty-eight patients with OLP and 30 age- and sex-matched healthy volunteers (HVs) were enrolled in the test group to probe the difference of salivary glycopatterns using lectin microarrays. The lectin blotting were further utilized to validate the expression of certain glycans. RESULTS: The glycoproteins recognized by three lectins [Aleuria aurantia lectin (AAL); Phytolacca americana (PWM); Phaseolus vulgaris agglutinin (E + L), (PHA-E + L)] were mainly increasing in the saliva of OLP. Meanwhile, these glycoproteins also exhibited significant age-associated alterations. CONCLUSIONS: This study provided a new basic insight into salivary glycopatterns in OLP and helped to develop new potential biomarkers for diagnosis of OLP.


Subject(s)
Glycoproteins/metabolism , Lichen Planus, Oral/metabolism , Saliva/metabolism , Salivary Proteins and Peptides/metabolism , Adult , Biomarkers/metabolism , Female , Glycosylation , Humans , Lectins/metabolism , Lichen Planus, Oral/diagnosis , Male , Middle Aged , Phytohemagglutinins/metabolism , Pokeweed Mitogens/metabolism , Young Adult
4.
J Dairy Sci ; 100(1): 750-756, 2017 Jan.
Article in English | MEDLINE | ID: mdl-27865492

ABSTRACT

A large number of studies recognize glucocorticoids (Gc) as suppressors of inflammation; Gc exert an important role in coordinating the magnitude and duration of host immune responses. In the present in vitro investigation, we tested incremental levels of cortisol to verify the immunosuppressive or immunopermissive role of cortisol in sheep peripheral blood mononuclear cells (PBMC) after acute and chronic stress. Phytohemagglutinin (PHA)-stimulated PBMC were cultured for 24h and 96h at 37°C with 5% of CO2 and varying cortisol levels: 10 ng/mL (baseline), 100 ng/mL (physiological poststressor), and 1,000 ng/mL [hyperactivated hypothalamic-pituitary-adrenal (HPA) axis]. The cell-free supernatants were collected for determination of IL-6, IL-1ß, and IL-10 by ELISA, and the bromodeoxyuridine assay was performed on cells. Physiological cortisol concentration negatively affected the levels of IL-6 secreted by PBMC, resulting in increased cell proliferation after acute stress (24h of incubation). However, physiological cortisol concentration exhibited a reduction in cell proliferation induced by increased levels of IL-6 secreted by PBMC during chronic stress (96h of incubation). The cortisol concentration representing a hyperactivated HPA axis led to a reduction in cell proliferation after acute stress, which was probably induced by the elevated IL-10 production. Our results demonstrate that in sheep the effect of Gc on the immune system was related to the magnitude and the duration of stress. In particular, cortisol levels higher than physiological concentrations suppressed cell proliferation soon after acute stress. Instead, the physiological poststressor concentration of cortisol affected the immune responses in a bidirectional manner depending on the duration of the stressor.


Subject(s)
Cell Proliferation , Hydrocortisone/blood , Leukocytes, Mononuclear/metabolism , Stress, Physiological , Animals , Female , Hypothalamic Area, Lateral/metabolism , Interleukin-10/metabolism , Interleukin-1beta/metabolism , Interleukin-6/metabolism , Leukocytes, Mononuclear/cytology , Phytohemagglutinins/metabolism , Sheep
5.
J Neurosci ; 35(48): 15812-26, 2015 Dec 02.
Article in English | MEDLINE | ID: mdl-26631464

ABSTRACT

Temporal coordination of neuronal assemblies among cortical areas is essential for behavioral performance. GABAergic projections from the medial septum and diagonal band complex exclusively innervate GABAergic interneurons in the rat hippocampus, contributing to the coordination of neuronal activity, including the generation of theta oscillations. Much less is known about the synaptic target neurons outside the hippocampus. To reveal the contribution of synaptic circuits involving the medial septum of mice, we have identified postsynaptic cortical neurons in wild-type and parvalbumin-Cre knock-in mice. Anterograde axonal tracing from the septum revealed extensive innervation of the hippocampus as well as the subiculum, presubiculum, parasubiculum, the medial and lateral entorhinal cortices, and the retrosplenial cortex. In all examined cortical regions, many septal GABAergic boutons were in close apposition to somata or dendrites immunopositive for interneuron cell-type molecular markers, such as parvalbumin, calbindin, calretinin, N-terminal EF-hand calcium-binding protein 1, cholecystokinin, reelin, or a combination of these molecules. Electron microscopic observations revealed septal boutons forming axosomatic or axodendritic type II synapses. In the CA1 region of hippocampus, septal GABAergic projections exclusively targeted interneurons. In the retrosplenial cortex, 93% of identified postsynaptic targets belonged to interneurons and the rest to pyramidal cells. These results suggest that the GABAergic innervation from the medial septum and diagonal band complex contributes to temporal coordination of neuronal activity via several types of cortical GABAergic interneurons in both hippocampal and extrahippocampal cortices. Oscillatory septal neuronal firing at delta, theta, and gamma frequencies may phase interneuron activity.


Subject(s)
Entorhinal Cortex/physiology , Hippocampus/physiology , Neural Pathways/physiology , Neurons/physiology , Septal Nuclei/physiology , Synapses/physiology , Animals , Fluorescent Dyes/metabolism , Male , Matrix Attachment Region Binding Proteins/metabolism , Mice , Mice, Inbred C57BL , Mice, Transgenic , Microscopy, Confocal , Microscopy, Electron , Nerve Tissue Proteins/metabolism , Neurons/ultrastructure , Parvalbumins/genetics , Parvalbumins/metabolism , Phytohemagglutinins/metabolism , Reelin Protein , Septal Nuclei/cytology , Synapses/ultrastructure , Vesicular Inhibitory Amino Acid Transport Proteins
6.
J Transl Med ; 14(1): 316, 2016 11 15.
Article in English | MEDLINE | ID: mdl-27846855

ABSTRACT

BACKGROUND: Sepsis is characterized by the loss of the perm-selectivity properties of the glomerular filtration barrier (GFB) with consequent albuminuria. We examined whether the pharmacokinetics-pharmacodynamics (PK/PD) of ceftriaxone (CTX), an extensively protein-bound 3rd generation cephalosporin, is altered during early sepsis and whether an increase in urinary loss of bound-CTX, due to GFB alteration, can occur in this condition. METHODS: A prospective, experimental, randomized study was carried out in adult male Sprague-Dawley rats. Sepsis was induced by cecal ligation and puncture (CLP). Rats were divided into two groups: Sham-operated and CLP. CTX (100 mg i.p., equivalent to 1 g dose in humans) was administered in order to measure plasma and lung CTX concentrations at several time-points: baseline and 1, 2, 4 and 6 h after administration. CTX was measured by High Performance Liquid Chromatography (HPLC). The morphological status of the sialic components of the GFB barrier was assessed by lectin histo-chemistry. Monte Carlo simulation was performed to calculate the probability of target attainment (PTA >90%) for 80 and 100% of Tfree > minimum inhibitory concentration (MIC) for 80 and 100% of dosing interval. MEASUREMENTS AND MAIN RESULTS: After CLP, sepsis developed in rats as documented by the growth of polymicrobial flora in the peritoneal fluid (≤1 × 101 CFU in sham rats vs 5 × 104-1 × 105 CFU in CLP rats). CTX plasma concentrations were higher in CLP than in sham rats at 2 and 4 h after administration (difference at 2 h was 47.3, p = 0.012; difference at 4 h was 24.94, p = 0.004), while lung penetration tended to be lower. An increased urinary elimination of protein-bound CTX occurred (553 ± 689 vs 149 ± 128 mg/L, p < 0.05; % of bound/total CTX 22 ± 6 in septic rats vs 11 ± 4 in sham rats, p < 0.01) and it was associated with loss of the GFB sialic components. According to Monte Carlo simulation a PTA > 90% for 100% of the dosing interval was reached neither for sham nor CLP rats using MIC = 1 mg/L, the clinical breakpoint for Enterobacteriacee. CONCLUSIONS: Sepsis causes changes in the PK of CTX and an alteration in the sialic components of the GFB, with consequent loss of protein-bound CTX. Among factors that can affect drug pharmacokinetics during the early phases of sepsis, urinary loss of both free and albumin-bound antimicrobials should be considered.


Subject(s)
Ceftriaxone/pharmacology , Ceftriaxone/pharmacokinetics , Sepsis/drug therapy , Animals , Cecum/drug effects , Cecum/pathology , Ceftriaxone/blood , Ceftriaxone/therapeutic use , Computer Simulation , Ligation , Male , Monte Carlo Method , Phytohemagglutinins/metabolism , Prospective Studies , Punctures , Rats, Sprague-Dawley , Sepsis/pathology
7.
Apoptosis ; 20(12): 1623-35, 2015 Dec.
Article in English | MEDLINE | ID: mdl-26437916

ABSTRACT

The antiproliferative and cytotoxic activity of glucolaxogenin and its ability to induce apoptosis and autophagy in cervical cancer cells are reported. We ascertained that glucolaxogenin exerts an inhibitory effect on the proliferation of HeLa, CaSki and ViBo cells in a dose-dependent manner. Analysis of DNA distribution in the cell-cycle phase of tumor cells treated with glucolaxogenin suggests that the anti-proliferative activity of this steroid is not always dependent on the cell cycle. Cytotoxic activity was evaluated by detection of the lactate dehydrogenase enzyme in supernatants from tumor cell cultures treated with the steroid. Glucolaxogenin exhibited null cytotoxic activity. With respect to the apoptotic activity, the generation of apoptotic bodies, the presence of active caspase-3 and annexin-V, as well as the DNA fragmentation observed in all tumor lines after treatment with glucolaxogenin suggests that this compound does indeed induce cell death by apoptosis. Also, a significantly increased presence of the LC3-II, LC3 and Lamp-1 proteins was evidenced with the ultrastructural existence of autophagic vacuoles in cells treated with this steroidal glycoside, indicating that glucolaxogenin also induces autophagic cell death. It is important to note that this compound showed no cytotoxic effect and did not affect the proliferative capacity of mononuclear cells obtained from normal human peripheral blood activated by phytohaemagglutinin. Thus, glucolaxogenin is a compound with anti-proliferative properties that induces programmed cell death in cancer cell lines, though it is selective with respect to normal lymphocytic cells. These findings indicate that this glycoside could have a selective action on tumor cells and, therefore, be worthy of consideration as a therapeutic candidate with anti-tumor potential.


Subject(s)
Antineoplastic Agents/pharmacology , Apoptosis/drug effects , Autophagy/drug effects , Cell Death/drug effects , Uterine Cervical Neoplasms/drug therapy , Annexin A5/metabolism , Caspase 3/metabolism , Cell Cycle/drug effects , Cell Line, Tumor , Cell Proliferation/drug effects , DNA Fragmentation/drug effects , Female , Glycosides/metabolism , HeLa Cells , Humans , L-Lactate Dehydrogenase/metabolism , Leukocytes, Mononuclear/drug effects , Leukocytes, Mononuclear/metabolism , Phytohemagglutinins/metabolism , Uterine Cervical Neoplasms/metabolism , Uterine Cervical Neoplasms/pathology
8.
Mol Cell Probes ; 29(2): 129-34, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25725345

ABSTRACT

The susceptibility of the host to influenza virus is determined by the distribution of the sialic acid (SA) receptors on host cell membrane. Avian influenza virus (AIV) preferentially binds to SA α-2,3-galactose (SA α2,3-gal) linked receptors, while human strains bind to sialic acid α2,6-galactose (SA α2,6-gal) linked receptors. Here, we describe the SA patterns and distributions in the reproductive tract of hens by employing two specific lectins, Maackia amurensis agglutinin (MAA) for SA α2,3-gal and sambucus nigra agglutinin (SNA) for SA α 2,6-gal receptors. Our results revealed that both SA α2,3-gal and SA α2,6-gal receptors exist in the reproductive tract of hens, including magnum, isthmus, uterus and vagina except for infundibulum. The distribution of SAα-2,3-gal receptor was more abundantly in the columnar epithelium cells of magnum, isthmus and uterus. Only minimal positive results for SA α-2,6-gal receptors were detected in the columnar epithelium cells of magnum, isthmus, uterus and vagina. Furthermore, AIV in tissues of the reproductive tract tissues of laying hens were detected by SYBR green-based reverse transcription and polymerase chain reaction (RT-PCR). Results showed that both viral loads and pathological changes in different parts of the reproductive tract were positively correlated with the expression of both receptors. Our results revealed that the reproductive tract of hens may provide an environment for the replication of both avian and human influenza viruses.


Subject(s)
Chickens/metabolism , Influenza in Birds/metabolism , Receptors, Cell Surface/metabolism , Receptors, Virus/analysis , Animals , Epithelial Cells , Phytohemagglutinins/metabolism , Reproduction , Sambucus nigra/metabolism , Viral Load
9.
J Neurosci ; 33(13): 5718-27, 2013 Mar 27.
Article in English | MEDLINE | ID: mdl-23536085

ABSTRACT

Previous studies in monkeys disclosed a specific arrangement of corticostriatal projections. Prefrontal and premotor areas form dense projection fields surrounded by diffuse terminal areas extending outside the densely innervated region and overlapping with projections from other areas. In this study, the mode of prefrontostriatal innervation was analyzed in rats using a 3D approach. Following injections of tracers in defined cortical areas, 3D maps from individual cases were elaborated and combined into a global 3D map allowing us to define putative overlaps between projection territories. In addition to providing a detailed 3D mapping of the topographic representation of prefrontal cortical areas in the rat striatum, the results stress important similarities between the rodent and primate prefrontostriatal projections. They share the dual pattern of focal and diffuse corticostriatal projections. Moreover, besides segregated projections consistent with parallel processing, the interweaving of projection territories establishes specific patterns of overlaps spatially organized along the dorsoventral, mediolateral, and anteroposterior striatal axis. In particular, the extensive striatal projection fields from the prelimbic and anterior cingulate areas, which partly overlap the terminal fields from medial, orbital, and lateral prefrontal cortical areas, provide putative domains of convergence for integration between reward, cognitive, and motor processes.


Subject(s)
Brain Mapping , Corpus Striatum/physiology , Neural Pathways/physiology , Prefrontal Cortex/physiology , Animals , Corpus Striatum/anatomy & histology , Electroencephalography , Imaging, Three-Dimensional , Male , Phytohemagglutinins/metabolism , Prefrontal Cortex/anatomy & histology , Rats , Rats, Sprague-Dawley
10.
Glycobiology ; 24(4): 368-78, 2014 Apr.
Article in English | MEDLINE | ID: mdl-24436051

ABSTRACT

Phytohemagglutinin from Phaseolus vulgaris (PHA-E), a legume lectin, has an unusual specificity toward biantennary galactosylated N-glycan with bisecting N-acetylglucosamine (GlcNAc). To investigate the interaction in detail, we have solved the crystal structures of PHA-E without ligand and in complex with biantennary N-glycan derivatives. PHA-E interacts with the trisaccharide unit (Galß1-4GlcNAcß1-2Man) in a manner completely different from that of mannose/glucose-specific legume lectins. The inner mannose residue binds to a novel site on the protein, and its rotation is opposite to that occurring in the monosaccharide-binding site of other lectins around the sugar O3 axis. Saturation-transfer difference NMR using biantennary di-galactosylated and bisected glycans reveals that PHA-E interacts with both antennas almost equally. The unique carbohydrate interaction explains the glycan-binding specificity and high affinity.


Subject(s)
Phaseolus/chemistry , Phytohemagglutinins/chemistry , Phytohemagglutinins/metabolism , Polysaccharides/metabolism , Models, Molecular , Molecular Conformation , Phytohemagglutinins/genetics , Polysaccharides/chemistry
11.
Glycobiology ; 24(6): 507-17, 2014 Jun.
Article in English | MEDLINE | ID: mdl-24658466

ABSTRACT

Carbohydrates participate in almost every aspect of biology from protein sorting to modulating cell differentiation and cell-cell interactions. To date, the majority of data gathered on glycan expression has been obtained via analysis with either anti-glycan antibodies or lectins. A detailed understanding of the specificities of these reagents is critical to the analysis of carbohydrates in biological systems. Glycan microarrays are increasingly used to determine the binding specificity of glycan-binding proteins (GBPs). In this study, six different glycan microarray platforms with different modes of glycan presentation were compared using five well-known lectins; concanavalin A, Helix pomatia agglutinin, Maackia amurensis lectin I, Sambucus nigra agglutinin and wheat germ agglutinin. A new method (universal threshold) was developed to facilitate systematic comparisons across distinct array platforms. The strongest binders of each lectin were identified using the universal threshold across all platforms while identification of weaker binders was influenced by platform-specific factors including presentation of determinants, array composition and self-reported thresholding methods. This work compiles a rich dataset for comparative analysis of glycan array platforms and has important implications for the implementation of microarrays in the characterization of GBPs.


Subject(s)
Carrier Proteins/metabolism , Microarray Analysis , Polysaccharides/metabolism , Binding Sites , Carbohydrates/biosynthesis , Carrier Proteins/chemistry , Concanavalin A/chemistry , Concanavalin A/metabolism , Lectins/chemistry , Lectins/metabolism , Phytohemagglutinins/chemistry , Phytohemagglutinins/metabolism , Polysaccharides/chemistry , Wheat Germ Agglutinins/chemistry , Wheat Germ Agglutinins/metabolism
12.
Clin Exp Rheumatol ; 32(3): 383-9, 2014.
Article in English | MEDLINE | ID: mdl-24564990

ABSTRACT

OBJECTIVES: The ImmuKnow (Cylex) assay has been reported to predict the risk of infection in some diseases; however, it is uncertain whether ImmuKnow can predict the risk of infection in lupus nephritis (LN) patients receiving immunosuppressive therapy. METHODS: The ImmuKnow Immune Cell Function Assay (Cylex, Inc., Columbia, MD, USA) was applied to measure the activity of CD4+ T cells, as a marker of global immune-competence. The correlation between changes in T cell activation and the relative risk of over-immunosuppression as well as infection was studied. The amount of adenosine triphosphate (ATP) produced by CD4+ T cells in response to phytohemagglutinin (PHA) was measured for 74 LN patients without infection, 22 LN patients with severe infection (i.e. required hospitalisation), and 28 healthy controls. RESULTS: No correlation was found between the ATP level and systemic lupus erythematosus (SLE) activity. The mean ATP level was significantly lower in LN patients with infection than that in healthy controls (p<0.01) and non-infected LN patients (p<0.01). The mean ATP level in non-infected LN patients was not significantly different compared to healthy controls. A cut-off ATP value of 300 ng/mL predicted infection in LN patients with a specificity of 77% and a sensitivity of 77%. Multi-variable partial correlation coefficient between the ATP assay and severe infection was r =-0.040, p<0.001; CRP was r=0.962, p<0.001. CONCLUSIONS: The ImmuKnow assay may be effective in identifying an increased risk of infection in LN patients but is not correlated with SLE activity. Combined CRP value will increase the diagnostic rate of severe infection in SLE. Larger studies are required to establish clinical advantages of this assay in SLE treatment.


Subject(s)
Adenosine Triphosphate/metabolism , CD4-Positive T-Lymphocytes/metabolism , Immunologic Tests/methods , Lupus Nephritis/immunology , Opportunistic Infections/diagnosis , Adult , CD4-Positive T-Lymphocytes/immunology , Female , Humans , Immunosuppressive Agents/adverse effects , Lupus Erythematosus, Systemic/drug therapy , Lupus Erythematosus, Systemic/epidemiology , Lupus Erythematosus, Systemic/immunology , Lupus Nephritis/drug therapy , Lupus Nephritis/epidemiology , Male , Middle Aged , Opportunistic Infections/epidemiology , Opportunistic Infections/immunology , Phytohemagglutinins/metabolism , Predictive Value of Tests , ROC Curve , Risk Factors , Sensitivity and Specificity , Young Adult
13.
Nat Med ; 13(2): 147-9, 2007 Feb.
Article in English | MEDLINE | ID: mdl-17206149

ABSTRACT

Poor human-to-human transmission of influenza A H5N1 virus has been attributed to the paucity of putative sialic acid alpha2-3 virus receptors in the epithelium of the human upper respiratory tract, and thus to the presumed inability of the virus to replicate efficiently at this site. We now demonstrate that ex vivo cultures of human nasopharyngeal, adenoid and tonsillar tissues can be infected with H5N1 viruses in spite of an apparent lack of these receptors.


Subject(s)
Influenza A Virus, H5N1 Subtype/metabolism , Influenza, Human/transmission , Receptors, Cell Surface/metabolism , Respiratory System/virology , Virus Attachment , Cells, Cultured , Epithelium/virology , Histocytochemistry , Hong Kong , Humans , Influenza A Virus, H1N1 Subtype/metabolism , Influenza A Virus, H3N2 Subtype/metabolism , Influenza, Human/metabolism , Phytohemagglutinins/metabolism , Virus Replication/physiology
14.
Brain Res ; 1824: 148686, 2024 02 01.
Article in English | MEDLINE | ID: mdl-38008243

ABSTRACT

Alzheimer's disease (AD) is a multifactorial,neurodegenerative disorder linked withextracellular amyloid beta (Aß) plaques deposition and formation of intracellular neurofibrillary tangles (NFTs). Currently, no effective therapies are available to cure AD. Neuroinflammation isa well-known hallmark in the onset and advancement of AD and triggering receptor expressed on myeloid cells-2 (TREM-2), a microglial gene, is responsible for regulating inflammatory responses and clearance of cellular debris. Loss of TREM-2functionincreases neuroinflammation associated expression of pro-inflammatory markersthus resultingin reduced clearance of Aß that further aid in disease progression.Therefore, targeting neuroinflammation is a good therapeutic approach for AD. This study aimed to determine the neuroprotective effect of nicotinic acid (NA) in vitro model of AD-like pathology induced in F-98 cell line using Phytohemagglutinin (PHA). MTT assay was employed for checking the cell viability as well as the proliferation of the cells following treatment with NA. PHA at the concentration of 10 µg/mL produces maximum plaques. The neuroprotective effect of NA was next evaluated against PHA-induced plaques and it was observed that NA reverses the damages induced by PHA i.e., by inhibiting the clustering of the cells and replacing the damaged cells with the new ones. Further, NA also increased the expression of TREM-2/DAP-12 with parallel decreased in the expression of IL-1ß, TNF-α and iNOS. It also successfully altered disease associated ADAM-10 and BACE-1 compared to PHA control. These findings suggest that NA might be considered as a good therapeutic candidate for the treatment of neurodegenerative disorders like AD.


Subject(s)
Alzheimer Disease , Neuroprotective Agents , Niacin , Humans , Alzheimer Disease/metabolism , Amyloid beta-Peptides/metabolism , Phytohemagglutinins/metabolism , Phytohemagglutinins/pharmacology , Phytohemagglutinins/therapeutic use , Microglia/metabolism , Niacin/metabolism , Niacin/pharmacology , Niacin/therapeutic use , Neuroprotective Agents/therapeutic use , Neuroinflammatory Diseases
15.
J Nat Med ; 78(2): 355-369, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38265611

ABSTRACT

Chemotherapy is still a prevalent strategy for clinical lung cancer treatment. However, the inevitable emerged drug resistance has become a great hurdle to therapeutic effect. Studies have demonstrated that the primary cause of drug resistance is a decrease in the chemotherapeutic medicine concentration. Several lectins have been confirmed to be effective as chemotherapy adjuvants, enhancing the anti-tumor effects of chemotherapy drugs. Here, we combined phytohemagglutinin (PHA), which has been reported possess anti-tumor effects, with chemotherapy drugs Cisplatin (DDP) and Adriamycin (ADM) on lung cancer cells to detect the sensitivities of PHA as a chemotherapy adjuvant. Our results demonstrated that the PHA significantly enhanced the sensitivity of lung cancer cells to DDP and ADM, and Western blot showed that PHA combined with DDP or ADM enhance cytotoxic effects by inhibiting autophagy and promoting apoptosis. More importantly, we found PHA enhanced the chemotherapeutic drugs cytotoxicity by changing the cell membrane to increase the intracellular chemotherapeutic drugs concentration. Besides, the combination of PHA and ADM increased the ADM concentration in the multidrug-resistant strain A549-R cells and achieved the drug sensitization effect. Our results suggest that PHA combined with chemotherapy can be applied in the treatment of lung cancer cells and lung cancer multidrug-resistant strains, and provide a novel strategy for clinical tumor chemotherapy and a new idea to solve the problem of drug resistance in clinical lung cancer.


Subject(s)
Antineoplastic Agents , Lung Neoplasms , Phaseolus , Humans , Lung Neoplasms/drug therapy , Lung Neoplasms/pathology , Phytohemagglutinins/pharmacology , Phytohemagglutinins/metabolism , Phytohemagglutinins/therapeutic use , Phaseolus/metabolism , Cell Membrane Permeability , Drug Resistance, Neoplasm , Cell Line, Tumor , Antineoplastic Agents/pharmacology , Antineoplastic Agents/therapeutic use , Doxorubicin/pharmacology , Doxorubicin/therapeutic use , Apoptosis , Cell Proliferation
16.
J Neurosci ; 32(8): 2886-99, 2012 Feb 22.
Article in English | MEDLINE | ID: mdl-22357871

ABSTRACT

Choosing between smaller, assured rewards or larger, uncertain ones requires reconciliation of competing biases toward more certain or riskier options. We used disconnection and neuroanatomical techniques to reveal that separate, yet interconnected, neural pathways linking the medial prefrontal cortex (PFC), the basolateral amygdala (BLA), and nucleus accumbens (NAc) contribute to these different decision biases in rats. Disrupting communication between the BLA and NAc revealed that this subcortical circuit biases choice toward larger, uncertain rewards on a probabilistic discounting task. In contrast, disconnections between the BLA and PFC increased choice of the Large/Risky option. PFC-NAc disconnections did not affect choice but did increase choice latencies and trial omissions. Neuroanatomical studies confirmed that projection pathways carrying axons from BLA-to-PFC transverse a distinctly different route relative to PFC-to-BLA pathways (via the ventrolateral amydalofugal pathway and ventromedial internal capsule, respectively). We exploited these dissociable axonal pathways to selectively disrupt bottom-up and top-down communication between the BLA and PFC. Subsequent disconnection studies revealed that disruption of top-down (but not bottom-up) information transfer between the medial PFC and BLA increased choice of the larger, riskier option, suggesting that this circuit facilitates tracking of actions and outcomes to temper urges for riskier rewards as they become less profitable. These findings provide novel insight into the dynamic competition between these cortical/subcortical circuits that shape our decision biases and underlie conflicting urges when evaluating options that vary in terms of potential risks and rewards.


Subject(s)
Amygdala/physiology , Brain Mapping , Decision Making/physiology , Nucleus Accumbens/physiology , Prefrontal Cortex/physiology , Reward , Analysis of Variance , Animals , Biotin/analogs & derivatives , Biotin/metabolism , Choice Behavior , Conditioning, Operant/physiology , Corpus Callosum/physiology , Corpus Callosum/surgery , Dextrans/metabolism , Discrimination, Psychological , Functional Laterality , Male , Neural Pathways/physiology , Phytohemagglutinins/metabolism , Probability , Rats , Rats, Long-Evans , Reaction Time/physiology
17.
Biochem Biophys Res Commun ; 436(3): 394-9, 2013 Jul 05.
Article in English | MEDLINE | ID: mdl-23747419

ABSTRACT

Influenza viruses (IFVs) recognize sialoglycans expressed on the host cell surface. To understand the mechanisms underlying tissue and host tropisms of IFV, it is essential to elucidate the molecular interaction of the virus with the host sialoglycan receptor. We established and applied a new monoclonal antibody, clone HYB4, which specifically recognizes the Neu5Acα2-3 determinant at the non-reducing terminal Gal residue of both glycoproteins and gangliosides to investigate the biochemical properties of IFV receptors in A549 cells. HYB4 significantly blocked virus binding to A549 cells in a dose-dependent manner. Virus overlay assay indicated that several glycoproteins with molecular masses of 80-120 kDa of A549 cells were commonly recognized by different subtypes of IFV, such as H1N1 and H3N2. H1N1 virus binding to the glycoproteins was diminished by pretreatment with either sialidase or PNGase F. On TLC-immunostaining experiments with HYB4, GM3 ganglioside was only detected in A549 cells. Interestingly, this antibody bound to GM3 gangliosides on TLC and plastic surfaces, but not on lipid bilayers. In comparison with the recognition of Maackia amurensis lectins, HYB4 exclusively recognized Neu5Acα2-3Galß1-4GlcNAc residues expressed on glycoproteins. These results strongly suggest that N-linked sialoglycans with the Neu5Acα2-3 determinant on several glycoproteins are receptors for influenza virus in A549 cells.


Subject(s)
Influenza A Virus, H1N1 Subtype/metabolism , Influenza A Virus, H3N2 Subtype/metabolism , Receptors, Virus/metabolism , Antibodies, Monoclonal/metabolism , Antibodies, Monoclonal/pharmacology , Antibody Specificity , Cell Line, Tumor , Dose-Response Relationship, Drug , G(M3) Ganglioside/metabolism , Host-Pathogen Interactions , Humans , Lipid Bilayers/metabolism , Maackia/chemistry , Membrane Glycoproteins/metabolism , Molecular Weight , Neuraminidase/pharmacology , Peptide-N4-(N-acetyl-beta-glucosaminyl) Asparagine Amidase/pharmacology , Phytohemagglutinins/metabolism , Plant Lectins/metabolism , Receptors, Cell Surface , Ribosome Inactivating Proteins/metabolism , Virus Attachment/drug effects
18.
Proc Biol Sci ; 280(1752): 20122228, 2013 Feb 07.
Article in English | MEDLINE | ID: mdl-23235701

ABSTRACT

Populations forced through bottlenecks typically lose genetic variation and exhibit inbreeding depression. 'Genetic rescue' techniques that introduce individuals from outbred populations can be highly effective in reversing the deleterious effects of inbreeding, but have limited application for the majority of endangered species, which survive only in a few bottlenecked populations. We tested the effectiveness of using highly inbred populations as donors to rescue two isolated and bottlenecked populations of the South Island robin (Petroica australis). Reciprocal translocations significantly increased heterozygosity and allelic diversity. Increased genetic diversity was accompanied by increased juvenile survival and recruitment, sperm quality, and immunocompetence of hybrid individuals (crosses between the two populations) compared with inbred control individuals (crosses within each population). Our results confirm that the implementation of 'genetic rescue' using bottlenecked populations as donors provides a way of preserving endangered species and restoring their viability when outbred donor populations no longer exist.


Subject(s)
Conservation of Natural Resources/methods , Genetic Fitness , Hybridization, Genetic , Polymorphism, Genetic , Songbirds/genetics , Animals , Endangered Species , Female , Genotype , Hemagglutination , Immunocompetence , Inbreeding , Male , Microsatellite Repeats , New Zealand , Phytohemagglutinins/metabolism , Population Dynamics , Sequence Analysis, DNA , Sequence Homology , Songbirds/immunology , Songbirds/physiology , Spermatozoa/physiology
19.
Theor Appl Genet ; 126(3): 647-61, 2013 Mar.
Article in English | MEDLINE | ID: mdl-23117719

ABSTRACT

In common bean (Phaseolus vulgaris L.), the most abundant seed proteins are the storage protein phaseolin and the family of closely related APA proteins (arcelin, phytohemagglutinin and α-amylase inhibitor). High variation in APA protein composition has been described and the presence of arcelin (Arc) has been associated with bean resistance against two bruchid beetles, the bean weevil (Acanthoscelides obtectus Say) and the Mexican bean weevil (Zabrotes subfasciatus Bohemian). So far, seven Arc variants have been identified, all in wild accessions, however, only those containing Arc-4 were reported to be resistant to both species. Although many efforts have been made, a successful breeding of this genetic trait into cultivated genotypes has not yet been achieved. Here, we describe a newly collected wild accession (named QUES) and demonstrate its resistance to both A. obtectus and Z. subfasciatus. Immunological and proteomic analyses of QUES seed protein composition indicated the presence of new Arc and arcelin-like (ARL) polypeptides of about 30 and 27 kDa, respectively. Sequencing of cDNAs coding for QUES APA proteins confirmed that this accession contains new APA variants, here referred to as Arc-8 and ARL-8. Moreover, bioinformatic analysis showed the two proteins are closely related to APA components present in the G12949 wild bean accession, which contains the Arc-4 variant. The presence of these new APA components, combined with the observations that they are poorly digested and remain very abundant in A. obtectus feces, so-called frass, suggest that the QUES APA locus is involved in the bruchid resistance. Moreover, molecular analysis indicated a lower complexity of the locus compared to that of G12949, suggesting that QUES should be considered a valuable source of resistance for further breeding purposes.


Subject(s)
Alleles , Genotype , Phaseolus/genetics , Plant Lectins/genetics , Weevils , Animals , Breeding , Computational Biology , DNA, Complementary/genetics , DNA, Complementary/isolation & purification , Electrophoresis, Polyacrylamide Gel , Genetic Loci , Phytohemagglutinins/genetics , Phytohemagglutinins/metabolism , Plant Lectins/metabolism , Proteomics , Sequence Analysis, DNA
20.
J Exp Biol ; 216(Pt 22): 4242-50, 2013 Nov 15.
Article in English | MEDLINE | ID: mdl-23997195

ABSTRACT

Life history parameters appear to be traded off against each other, but the physiological mechanisms involved remain unclear. One hypothesis is that potentially energetically costly processes such as immune function and protection from oxidative stress may be compromised during reproductive attempts because of selective resource allocation. Lower temperatures also impose energy costs, and hence allocation decisions might be more pronounced when animals are forced to reproduce in the cold. Here, we experimentally tested whether reproduction at different ambient temperatures was associated with elevated oxidative stress and suppressed immune function in Mongolian gerbils (Meriones unguiculatus). Using a variety of different markers for both immune function and oxidative stress, we found that some measures of immune function (serum bactericidal capacity and size of the thymus) were significantly suppressed, while some measures of oxidative protection [serum superoxide dismutase (SOD) activity and glutathione peroxidase (GPx) activity] were also reduced, and a marker of oxidative damage (protein carbonyls in serum) was increased in lactating compared with non-reproductive gerbils. These changes were in line with the selective resource allocation predictions. However, the phytohaemagglutinin response and serum total immunoglobulin (IgG) were not suppressed, and other markers of oxidative damage [malondialdehyde (MDA) (TBARS) and protein carbonyls in the liver] were actually lower in lactating compared with non-reproductive gerbils, consistent with increased levels of SOD activity and total antioxidant capacity in the liver. These latter changes were opposite of the expectations based on resource allocation. Furthermore, other measures of protection (GPx levels in the liver and protein thiols in both serum and liver) and damage [MDA (TBARS) in serum] were unrelated to reproductive status. Ambient temperature differences did not impact on these patterns. Collectively, our results indicated that the inferred effects of reproduction on immunosuppression and oxidative damage, and hence support or otherwise for particular physiological mechanisms that underpin life history trade-offs, are critically dependent on the exact markers and tissues used. This may be because during reproduction individuals selectively allocate protection to some key tissues, but sacrifice protection of others.


Subject(s)
Immune Tolerance/physiology , Oxidative Stress/physiology , Reproduction/physiology , Temperature , Analysis of Variance , Animals , Female , Gerbillinae , Glutathione Peroxidase/blood , Organ Size/physiology , Phytohemagglutinins/metabolism , Reproduction/immunology , Serum Bactericidal Test , Statistics, Nonparametric , Superoxide Dismutase/blood , Thiobarbituric Acid Reactive Substances , Thymus Gland/physiology
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