- GALNT6 Stabilizes GRP78 Protein by O-glycosylation and Enhances its Activity to Suppress Apoptosis Under Stress Condition. [Journal Article]
- NNeoplasia 2017; 19(1):43-53
- We previously reported that overexpression of an O-type glycosyltransferase, GALNT6 (polypeptide N-acetylgalactosaminyltransferase 6) played critical roles in mammary carcinogenesis. To further inves...
We previously reported that overexpression of an O-type glycosyltransferase, GALNT6 (polypeptide N-acetylgalactosaminyltransferase 6) played critical roles in mammary carcinogenesis. To further investigate the biological function of GALNT6, we screened a substrate protein(s) of GALNT6 using a VVA (Vicia villosa agglutinin) lectin (specific to GalNAc-Ser/Thr) pull-down method followed by mass spectrometry analysis. Here we report GRP78 (glucose-regulated protein 78, also known as HSPA5, heat shock 70 kDa protein 5), which is highly expressed in cancer cells and indicated to play important roles in various cellular processes including ER (endoplasmic reticulum) stress and autophagy, as a novel substrate of GALNT6. We found that GALNT6-induced O-glycosylation is critical for the stability of GRP78, its subcellular localization in ER, and its anti-apoptotic function. Furthermore, we demonstrated that overexpression of GRP78 could be important for Golgi-to-ER relocation of GALNT6. Collectively, our study revealed biological significances of O-glycosylation of GRP78 protein, which might play significant roles in the survival of cancer cells, and thus provided a new insight in cancer cell death and useful information for development of anti-cancer treatment targeting the GALNT6-GRP78 pathway.
- Age-Dependent Oxidative DNA Damage Does Not Correlate with Reduced Proliferation of Cardiomyocytes in Humans. [Journal Article]
- PlosPLoS One 2017; 12(1):e0170351
- CONCLUSIONS: Oxidative DNA damage of cardiomyocytes was not correlated positively with age in human beings. Oxidative DNA damage is unable to fully explain the reduced proliferation of human cardiomyocytes.
- Natural cytotoxicity receptor 1 in mouse uNK cell maturation and function. [Journal Article]
- MIMucosal Immunol 2017 Jan 18
- Early and midgestational decidua of mice genetically ablated for expression of the natural killer (NK) cell natural cytotoxicity receptor (NCR; Ncr1(Gfp/Gfp) mice) shows restricted angiogenesis and a...
Early and midgestational decidua of mice genetically ablated for expression of the natural killer (NK) cell natural cytotoxicity receptor (NCR; Ncr1(Gfp/Gfp) mice) shows restricted angiogenesis and atypically small uterine (u)NK cells . We hypothesized that NCR1 inactivation disturbs maturation and angiokine production by uterine natural killer (uNK) cells. Using histological and morphometric approaches, we observed that Ncr1(Gfp/Gfp) but not control C57BL/6 (B6) implantation sites sustain immature, non-granulated uNK cells into midpregnancy. Mouse uNK cells can be subclassified by their reactivity with Dolichos biflorus agglutinin (DBA) lectin; DBA+ uNK cells with greater Ncr1 expression were investigated. DBA+ uNK cells from Ncr1(Gfp/Gfp) mice show delayed maturation as indicated by shorter diameters and fewer cytoplasmic granules. Granules in mature Ncr1(Gfp/Gfp) uNK cells are ultrastructurally abnormal and abundance of granule-associated proteins (perforin, granzyme) and of cytoplasmic proteins (vascular endothelial growth factor; placental growth factor) differs from controls. Leukocyte-leukocyte conjugate formation in gestation day 6.5 and 8.5 intact Ncr1(Gfp/Gfp) decidua was less frequent than in B6; however, this difference involved leukocytes other than DBA+ uNK cells. These studies strongly support roles for NCR1 and its ligands in normal pregnancy promotion.Mucosal Immunology advance online publication, 18 January 2017; doi:10.1038/mi.2016.126.
- Binding of CLL subset 4 B-cell receptor immunoglobulins to viable human memory B lymphocytes requires a distinctive IGKV somatic mutation. [Journal Article]
- MMMol Med 2017 Jan 12; 23
- Amino acid replacement mutations in certain CLL stereotyped B-cell receptor (BCR) immunoglobulins (IGs) at defined positions within antigen-binding sites strongly imply antigen selection. Prime examp...
Amino acid replacement mutations in certain CLL stereotyped B-cell receptor (BCR) immunoglobulins (IGs) at defined positions within antigen-binding sites strongly imply antigen selection. Prime examples of this are CLL subset 4 BCR IGs using IGHV4-34/IGHD5-18/IGHJ6 and IGKV2-30/IGKJ2 rearrangements. Conspicuously and unlike most CLL IGs, subset 4 IGs do not bind apoptotic cells. By testing the (auto)antigenic reactivities of subset 4 IGs toward viable lymphoid-lineage cells and specific autoantigens typically bound by IGHV4-34(+) IGs, we found IGs from both subset 4 and non-subset 4 IGHV4-34-expressing CLL cases bind naïve B cells. However, only subset 4 IGs react with memory B cells. Furthermore, subset 4 IGs do not bind DNA nor i or I carbohydrate antigens, common targets of IGHV4-34-utilizing antibodies in systemic lupus erythematosus and cold agglutinin disease, respectively. Notably, we found that subset 4 IG binding to memory B lymphocytes depends on an aspartic acid at position 66 of FR3 in the rearranged IGKV2-30 gene; this amino acid residue is acquired by somatic mutation. Our findings illustrate the importance of positive and negative selection criteria for structural elements in CLL IGs and suggest that autoantigens driving normal B cells to become subset 4 CLL cells differ from those driving IGHV4-34(+) B cells in other diseases.
- Swainsonine-induced lysosomal storage disease in goats caused by the ingestion of Sida rodrigoi Monteiro in North-western Argentina. [Journal Article]
- TToxicon 2017 Jan 13
- There are numerous poisonous plants that can induce intralysosomal accumulation of glycoproteins and neurologic syndromes. Here we describe for the first time, a disease caused by ingesting Sida rodr...
There are numerous poisonous plants that can induce intralysosomal accumulation of glycoproteins and neurologic syndromes. Here we describe for the first time, a disease caused by ingesting Sida rodrigoi Monteiro in goats in North-western Argentina. The animals showed weight loss, indifference to the environment, unsteady gait and ataxia. Histopathologic studies showed vacuolization in cells of various organs, mainly in the CNS. The material deposited in the cells was positive for LCA (Lens culinaris agglutinin), WGA (Triticum vulgaris agglutinin), sWGA (succinyl-Triticum vulgaris agglutinin) and Con-A (Concanavalia ensiformis agglutinin) lectins. Finally, toxic levels of swansonine were identified in the plant. The present investigation allowed to recognize S. rodrigoi Monteiro poisoning as a plant induced α-mannosidosis.
- A chimeric protein of abrin and Abrus precatorius agglutinin that neutralizes abrin mediated lethality in mice. [Journal Article]
- TToxicon 2017 Jan 11
- Abrin, a type II ribosome inactivating protein from the Abrus precatorius plant, is extremely toxic. It has been shown to be 75 times more potent than its infamous sister toxin, ricin and their poten...
Abrin, a type II ribosome inactivating protein from the Abrus precatorius plant, is extremely toxic. It has been shown to be 75 times more potent than its infamous sister toxin, ricin and their potential use in bio-warfare is a cause of major concern. Although several vaccine candidates are under clinical trials for ricin, none are available against abrin. The present study proposes a chimeric protein, comprising of 1-123 amino acids taken from the A chain of abrin and 124-175 amino acids from Abrus precatorius agglutinin A chain, as a vaccine candidate against abrin intoxication. The design was based on the inclusion of the immunogenic region of the full length protein and the minimal essential folding domains required for inducing neutralizing antibody response. The chimera also contains the epitope for the only two neutralizing antibodies; D6F10 and A7C4, reported against abrin till now. Active immunisation with the chimera protected all the mice challenged with 45 X LD50 of abrin. Also, passive transfer of antibodies raised against the chimera rescued all mice challenged with 50 X LD50 of toxin. Hence the chimeric protein appears to be a promising vaccine candidate against abrin induced lethality.
- A New Vaccine Delivery Vehicle and Adjuvant Candidate: Bordetella Pertussis Inactivated Whole Cells Entrapped in Alginate Microspheres. [Journal Article]
- CPCurr Pharm Des 2017 Jan 12
- There is no doubt about whole cell pertussis vaccine efficacy, but it is necessary to improve the vaccine quality specially to decreasing its toxicity by obtaining good immunogenicity with low bacter...
There is no doubt about whole cell pertussis vaccine efficacy, but it is necessary to improve the vaccine quality specially to decreasing its toxicity by obtaining good immunogenicity with low bacteria number content. In this work, under optimum condition inactivated B. pertussis bacteria cells entrapped alginate microparticles were fabricated and in vivo immunogenicity and potency of new microparticle based vaccine evaluated in mice. Microspheres loaded inactive B. pertussis bacterium cells were prepared via an emulsification method and analyzed for morphology, size, polydispersity index, loading efficiency, loading capacity, release profile and in vivo potency. The inactivated bacterial suspension mixture prepared in this work was nontoxic and showed potent ED50 (1:333 of human dose) and preserved agglutinins 1, 2, 3. The optimum conditions for preparation of microparticles were achieved at alginate concentration 3.8% (w/v), CaCl2 8% (w/v), PLL 0.1% (w/v), hydrophilic surfactant 2.2 (%v/v), lipophilic surfactant 3.6 (%v/v), cross linking time 3min, homogenization rate 600 rpm, and alginate to CaCl2 solution ratio 4. Both empty and B. pertussis loaded microparticles were exhibited smooth surface texture and relatively spherical shape. The B. pertussis encapsulated microspheres fabricated under optimized conditions showed mean particle size 151.1 μm, polydispersity index 0.43, loading efficiency 89.6%, loading capacity 36.3%, and relatively constant release rate lasted to 15 days. In vivo immunogenicity and protection study against wild type challenge showed strongly higher potency (approximately 2.5 fold) of encapsulated B. pertussis organisms than non-encapsulated conventional aluminum hydroxide adsorbed vaccine. It can be concluded that microencapsulation of inactive B. pertussis cells appears to be a suitable approach for improve the wP vaccine quality, specially by obtaining good immunogenicity with low bacteria number content.
- Seroepidemiology of Human Brucellosis Among Blood Donors in Southern Ethiopia: Calling Attention to a Neglected Zoonotic Disease. [Journal Article]
- AJAm J Trop Med Hyg 2017 Jan 11; 96(1):88-92
- Human brucellosis is neglected in southern Ethiopia. Although traditional food processing practices and animal husbandry which increase the risk of brucellosis are common, it has not been properly st...
Human brucellosis is neglected in southern Ethiopia. Although traditional food processing practices and animal husbandry which increase the risk of brucellosis are common, it has not been properly studied yet. This study was conducted to determine the seroepidemiology of brucellosis among apparently healthy individuals in southern Ethiopia. In the study, blood samples were collected to screen for serum agglutinins reactive to stained antigen of Brucella abortus Standard tube titration was performed for reactive serum to determine the titer of the agglutinin. A structured questionnaire was used to collect data on possible risk factors for brucellosis. The seroprevalence of human brucellosis in this study was found to be 10.6% (95% confidence interval = 7.0, 14.0). Possession of domestic ruminant animals, contact with ruminant animals, and husbandry practices at home were associated with seropositivity. The higher seroprevalence of human brucellosis in the study area needs attention and additional confirmatory investigation.
- Anti-Neuroblastoma Properties of a Recombinant Sunflower Lectin. [Journal Article]
- IJInt J Mol Sci 2017 Jan 10; 18(1)
- According to their sugar recognition specificity, plant lectins are proposed as bioactive proteins with potential in cancer treatment and diagnosis. Helja is a mannose-specific jacalin-like lectin fr...
According to their sugar recognition specificity, plant lectins are proposed as bioactive proteins with potential in cancer treatment and diagnosis. Helja is a mannose-specific jacalin-like lectin from sunflower which was shown to inhibit the growth of certain fungi. Here, we report its recombinant expression in a prokaryotic system and its activity in neurobalstoma cells. Helja coding sequence was fused to the pET-32 EK/LIC, the enterokinase/Ligation-independent cloning vector and a 35 kDa protein was obtained in Escherichia coli representing Helja coupled to thioredoxin (Trx). The identity of this protein was verified using anti-Helja antibodies. This chimera, named Trx-rHelja, was enriched in the soluble bacterial extracts and was purified using Ni(+2)-Sepharose and d-mannose-agarose chromatography. Trx-rHelja and the enterokinase-released recombinant Helja (rHelja) both displayed toxicity on human SH-SY5Y neuroblastomas. rHelja decreased the viability of these tumor cells by 75% according to the tetrazolium reduction assay, and microscopic analyses revealed that the cell morphology was disturbed. Thus, the stellate cells of the monolayer became spheroids and were isolated. Our results indicate that rHelja is a promising tool for the development of diagnostic or therapeutic methods for neuroblastoma cells, the most common solid tumors in childhood.
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- Synaptic contact between median preoptic neurons and subfornical organ neurons projecting to the paraventricular hypothalamic nucleus. [Journal Article]
- EBExp Brain Res 2017 Jan 09
- It is known that the median preoptic nucleus (POMe) sends dense projections to the subfornical organ (SFO). However, the functional significance of these projections have not been well discussed. In ...
It is known that the median preoptic nucleus (POMe) sends dense projections to the subfornical organ (SFO). However, the functional significance of these projections have not been well discussed. In this electron microscopic study, we investigated the presence of synapses between POMe-derived axon terminals and SFO neurons that project to the paraventricular hypothalamic nucleus (PVN). After injection of a retrograde tracer, wheat germ agglutinin-conjugated horseradish peroxidase-colloidal gold complex, into the PVN, many labeled neurons were found in the SFO. In contrast, after injection of an anterograde tracer, biotinylated dextran amine, in the POMe, abundant labeled axon varicosities were observed in the SFO. Using electron microscopy, synapses were identified between retrogradely labeled dendrites and cell bodies, and anterogradely labeled axon terminals, indicating that POMe neurons innervate SFO neurons projecting to the PVN. The possibility that POMe neurons play multiple roles in the neuronal circuit responsible for vasopressin release and/or cardiovascular regulation is also discussed.