Expanding the understanding of viral tropism by characterizing the N-glycomic profiles of transducible cell lines and tissue types and Characterizing functional receptors that mediate the inhibitory relationship between 4-O-sulfated chondroitin sulfate and neurons

2021 ◽  
Author(s):  
◽  
Jorden Tahquechi
Keyword(s):  
Gene Therapy ◽  
Sialic Acid ◽  
Chondroitin Sulfate ◽  
Cell Lines ◽  
Protein Tyrosine Phosphatase ◽  
Tyrosine Phosphatase ◽  
Structural Determinants ◽  
Arylsulfatase B ◽  
Gene Therapy Vectors ◽  
Viral Transduction

Abstract 1: Glycosylation plays an important role in facilitating viral transduction by acting as preliminary cell surface receptors. For this reason, the structural determinants in glycans that dictate viral tissue tropism need to be extensively studied to improve the efficacy of gene therapy vectors in basic research and eventually the clinic. Elucidating the dependencies for viral transduction initiation and understanding how these structural nuances of glycans initiate virion specific tropic effects is paramount when considering how to use vectors to improve clinical outcomes for patients suffering from illnesses with few treatment options. The goal of this project was to use MALDI-TOF-MS to provide baseline N-glycan profiles of the cell lines and tissues used to test gene therapy vectors. In doing so these profiles will be valuable to the field by clarifying what structural determinants may influence viral tropism. It was discovered Neu5Ac sialic acid content differs qualitatively amongst the seven cell lines analyzed. These differences may play into why some cell lines such as CHO-K1 and COS-7 can transduce more preferentially with some AAV serotypes like AAV5. In addition, sialic acid differences were also assessed in three tissue types used in transduction assays. Abstract 2: After injury to the CNS, reactive astrocytes form a protective extracellular matrix to isolate damaged tissue. These astrocytes influence the surrounding tissue by upregulating the production of proteoglycans containing chondroitin sulfate. Due to the new cellular environment, chondroitin sulfate (CS) glycosaminoglycan chains are upregulated with predominately 4-O-sulated sulfation patterns. These sulfation patterns are known to inhibit axonal guidance, and ultimately neuronal regeneration. While the inhibitory effect of CS is well known, the mechanism by which these specific sulfation patterns may interact with receptors also known to have inhibitory effects on neuro-regeneration such as protein tyrosine phosphatase σ is unknown. To characterize these interactions reductive amination was used to immobilize these CS chains onto solid beads. Chondroitin sulfate was isolated from the organs of an ARSB null mouse model which lacks the N-acetylgalactosamine-4-sulfatase (arylsulfatase B, ARSB) which is involved in the degradation of glycosaminoglycans (GAGs). Disruption of arylsulfatase B leads to the production of CS chains with 4-O-sulfated non-reducing ends exclusively. Key findings indicate that purified GAG chains retain their ligand specificity after being covalently immobilized onto solid supports, and that these systems can be utilized to characterize the relationship between inhibitory forms of CS and protein tyrosine phosphatase σ.

scholarly journals Role of Chondroitin Sulfate (CS) Modification in the Regulation of Protein-tyrosine Phosphatase Receptor Type Z (PTPRZ) Activity

2016 ◽  
Vol 291 (35) ◽  
pp. 18117-18128 ◽  
Author(s):  
Kazuya Kuboyama ◽  
Akihiro Fujikawa ◽  
Ryoko Suzuki ◽  
Naomi Tanga ◽  
Masaharu Noda
Keyword(s):  
Chondroitin Sulfate ◽  
Protein Tyrosine Phosphatase ◽  
Tyrosine Phosphatase ◽  
Receptor Type ◽  
Protein Tyrosine

The Receptor Protein Tyrosine Phosphatase, PTP-RO, Is Upregulated During Megakaryocyte Differentiation and Is Associated With the c-Kit Receptor

Blood ◽  
1999 ◽  
Vol 94 (2) ◽  
pp. 539-549 ◽  
Author(s):  
Yoshitaka Taniguchi ◽  
Roanna London ◽  
Karin Schinkmann ◽  
Shuxian Jiang ◽  
Hava Avraham
Keyword(s):  
Bone Marrow ◽  
Tyrosine Kinase ◽  
Cell Lines ◽  
Protein Tyrosine Phosphatase ◽  
Tyrosine Phosphatase ◽  
Tyrosine Kinase Receptor ◽  
Transfected Cells ◽  
Kit Ligand ◽  
Kit Receptor ◽  
Megakaryocytic Cell

Abstract We have recently isolated a cDNA encoding a novel human receptor-type tyrosine phosphatase, termed PTP-RO (for a protein tyrosine phosphatase receptor omicron), from 5-fluorouracil–treated murine bone marrow cells. PTP-RO is a human homologue of murine PTPλ and is related to the homotypically adhering κ and μ receptor-type tyrosine phosphatases. PTP-RO is expressed in human megakaryocytic cell lines, primary bone marrow megakaryocytes, and stem cells. PTP-RO mRNA and protein expression are upregulated upon phorbol 12-myristate 13-acetate (PMA) treatment of the megakaryocytic cell lines CMS, CMK, and Dami. To elucidate the function of PTP-RO in megakaryocytic cells and its potential involvement in the stem cell factor (SCF)/c-Kit receptor pathway, COS-7 and 293 cells were cotransfected with the cDNAs of both the c-Kit tyrosine kinase receptor and PTP-RO. PTP-RO was found to be associated with the c-Kit receptor in these transfected cells and the SCF/Kit ligand induced a rapid tyrosine phosphorylation of PTP-RO. Interestingly, these transfected cells demonstrated a decrease in their proliferative response to the SCF/Kit ligand. In addition, we assessed the association of PTP-RO with c-Kit in vivo. The results demonstrated that PTP-RO associates with c-Kit but not with the tyrosine kinase receptor FGF-R and that PTP-RO is tyrosine-phosphorylated after SCF stimulation of Mo7e and CMK cells. Antisense oligonucleotides directed against PTP-RO mRNA sequences significantly inhibited megakaryocyte progenitor proliferation. Therefore, these data show that the novel tyrosine kinase phosphatase PTP-RO is involved in megakaryocytopoiesis and that its function is mediated by the SCF/c-Kit pathway.

Deletion of the Protein Tyrosine Phosphatase Gene PTPN2 in T-Cell Acute Lymphoblastic Leukemia.

Blood ◽  
2009 ◽  
Vol 114 (22) ◽  
pp. 141-141
Author(s):  
Maria Kleppe ◽  
Idoya Lahortiga ◽  
Tiama El Chaar ◽  
Kim De Keersmaecker ◽  
Nicole Mentens ◽  
...  
Keyword(s):  
T Cell ◽  
Cell Lines ◽  
Protein Tyrosine Phosphatase ◽  
Lymphoblastic Leukemia ◽  
Tyrosine Phosphatase ◽  
Janus Kinase ◽  
Negative Regulator ◽  
Aberrant Expression ◽  
Protein Tyrosine ◽  
Knock Down

Abstract Abstract 141 Introduction: T-cell lymphoblastic leukemia (T-ALL) arises from clonal expansion of a lymphoid progenitor that has undergone stepwise alteration at distinct stages of differentiation. It is suggested that a set of cooperative mutations that affect different pathways are required before thymocytes become fully malignant. Despite major improvements in our understanding of the molecular genetics of T-ALL, the underlying mechanisms that lead to the abnormal proliferation and enhanced survival of the leukemic cells remain largely unknown. Results: Array CGH analysis revealed an acquired homozygous microdeletion at chromosome 18p11 in 6 % of T-ALL cases. The deleted region was only 125 kb in size and restricted to the PTPN2 (protein tyrosine phosphatase, non-receptor type 2) locus. PTPN2 encodes an intracellular non-transmembrane tyrosine-specific phosphatase that functions as a negative regulator of a variety of signaling proteins including several members of the janus kinase (JAK) and of signal transducer and activator of transcription (STAT) families, growth factor receptors and SRC family kinases. Homozygous deletion of PTPN2 was specifically found in cases with aberrant expression of the TLX1 transcription factor, with two cases also harboring the NUP214-ABL1 fusion. Analysis of additional TLX1 positive cases by quantitative PCR identified loss of one copy of PTPN2 in 5 out of 20 cases. No mutations were detected in the coding region of PTPN2. To determine the effect of loss of PTPN2 in T-cells, we downregulated the expression of PTPN2 using RNAi technology. siRNA mediated knock-down of PTPN2 affected activation of JAK1 associated cytokine receptors implicated in T-cell development. Ligand stimulation of IL7 and interferon gamma receptor resulted in an augmented and prolonged phosphorylation of JAK1 as well as downstream targets STAT1 and STAT5 in T-ALL cell lines with knock-down of PTPN2. In addition, knock- down of Ptpn2 sensitized the pro B-cell line Ba/F3 to transformation by wild type JAK1 confirming a clear relationship between loss of PTPN2 and JAK1 activation. Knock-down of PTPN2 expression also provided a proliferative advantage and reduced sensitivity to kinase inhibitors in lymphoblastic leukemia cell lines HSB-2 and ALL-SIL. Conclusion: In conclusion, our data provide genetic and functional evidence for a tumor suppressor role of PTPN2 in T-ALL and warrant testing of JAK inhibitors for the treatment of this specific subset of T-ALLs as well as further analysis of a potential negative impact of loss of PTPN2 on responsiveness to anti-cancer treatments. Disclosures: Ferrando: Merck, Pfizer: Research Funding.

Establishment and characterization of pro-B cell lines from motheaten mutant mouse defective in SHP-1 protein tyrosine phosphatase

1998 ◽  
Vol 63 (2) ◽  
pp. 75-82 ◽  
Author(s):  
Akitomo Miyamoto ◽  
Takahiro Kunisada ◽  
Hidetoshi Yamazaki ◽  
Kensuke Miyake ◽  
Shin-Ichi Nishikawa ◽  
...  
Keyword(s):  
B Cell ◽  
Cell Lines ◽  
Protein Tyrosine Phosphatase ◽  
Mutant Mouse ◽  
Tyrosine Phosphatase ◽  
Protein Tyrosine

scholarly journals The Cell-Specific Phenotype of the Polymorphic vacA Midregion Is Independent of the Appearance of the Cell Surface Receptor Protein Tyrosine Phosphatase β

2006 ◽  
Vol 74 (1) ◽  
pp. 49-55 ◽  
Author(s):  
David A. G. Skibinski ◽  
Christophe Genisset ◽  
Silvia Barone ◽  
John L. Telford
Keyword(s):  
Cell Surface ◽  
Cell Lines ◽  
Protein Tyrosine Phosphatase ◽  
Tyrosine Phosphatase ◽  
Cell Surface Receptor ◽  
Receptor Protein ◽  
Protein Tyrosine ◽  
Amino Acid Region ◽  
Receptor Protein Tyrosine Phosphatase ◽  
Surface Receptor

ABSTRACT There are two alleles, m1 and m2, of the midregion of the vacuolating cytotoxin gene (vacA) of Helicobacter pylori which code for toxins with different cell specificities. Here we describe the construction of five chimeric strains in which regions of vacA were exchanged between the two genotypes. By analyzing the toxicity of these strains for HeLa and RK13 cells we have confirmed that a 148-amino-acid region determines the phenotypic differences between the two forms of the protein and that this entire region is important for cytotoxicity. Furthermore, we have used our chimeric strains to investigate whether variations in the midregion of VacA have an effect on phorbol 12-myristate 13-acetate (PMA)-induced VacA sensitivity in HL-60 cells. The PMA-induced VacA sensitivity of HL-60 cells has been previously associated with the appearance of the cell surface receptor protein tyrosine phosphatase beta (RPTPβ). Our data indicate that both the m1 and m2 forms of VacA are able to utilize RPTPβ, and the cell-specific phenotype of the midregion is independent of the presence of RPTPβ. It appears that another as-yet-unidentified receptor exists in HL-60 cells that accounts for the m2 phenotype in this cell line. Also, by studying the effect of PMA on levels of RPTPβ in other cell lines and toxicity of VacA in these cell lines we have shown that RPTPβ does not play a major role in the vacuolation of HeLa cells.

Aberrant Epigenetic Suppression of the Ptprot Gene Encoding a Protein Tyrosine Phosphatase Targeting KIT in Acute Myeloid Leukemia

Blood ◽  
2012 ◽  
Vol 120 (21) ◽  
pp. 1322-1322
Author(s):  
Tasneem Motiwala ◽  
Satavisha Roy ◽  
Shujun Liu ◽  
Sebastian Schwind ◽  
Rainer Claus ◽  
...  
Keyword(s):  
Bone Marrow ◽  
Tyrosine Kinase ◽  
Cell Lines ◽  
Protein Tyrosine Phosphatase ◽  
Tyrosine Phosphatase ◽  
Catalytic Site ◽  
Protein Tyrosine ◽  
Hypomethylating Agent ◽  
Epigenetic Suppression ◽  
Oncogenic Function

Abstract Abstract 1322 Recent studies have suggested that deregulated expression of tyrosine phosphatases and the resulting alteration in the phosphorylation status of their substrates play a significant role in the oncogenic function of tyrosine-phosphorylated proteins. Over the past decade we have been studying the tumor suppressive function of protein tyrosine phosphatase receptor-type O (PTPRO). The gene for PTPRO encodes two functional isoforms, full-length form (PTPRO-FL) and a truncated form (PTPROt) that are expressed in a tissue-specific manner. PTPROt is primarily expressed in hematopoietic cells. It is, however, transcriptionally and epigenetically suppressed in CLL-like cell lines and primary CLL [Clin Cancer Res. 2007 Jun 1;13(11):3174–81, Blood. 2011 Dec 1;118(23):6132–40]. We have now shown that PTPROt is also hypermethylated in a discovery set of primary AML samples (n=77) provided by the University hospital Ulm biobank relative to bone marrow from normal controls. Analysis of the AML cell lines Kasumi-1 and ME-1 cells also showed dramatically reduced PTPROt expression relative to THP-1 and MV4-11 cells. Treatment of Kasumi-1 cells with the hypomethylating agent decitabine led to re-activation of PTPROt at both RNA and protein levels. PTPRO CpG island (CGI), methylated in Kasumi-1 cells, became hypomethylated following treatment with decitabine. Similarly, bone marrow samples from elderly AML patients who received decitabine 20 mg/m2/day – 10 days on the OSU 07017 study exhibited hypomethylation and upregulation of PTPROt. To further evaluate the functional significance of hypermethylation and silencing of PTPROt in AML, we then searched for potential kinase substrates of the protein. Kasumi-1 and ME-1 cells (where PTPROt is suppressed) are both CBF cell lines characterized by RUNX1/RUNX1T1 [(8;21) translocation] and CBFB/MYH11 [inv(16)], respectively. While CBF AML patients are generally classified within a more favorable cytogenetic group, those cases harboring mutation in the KIT gene that results in constitutively active receptor tyrosine kinase have a poor outcome. In addition, increased expression of the encoded kinase protein occurs in ∼80% of CBF AML, regardless of KIT mutational status. Kasumi-1 and ME-1 cells are also characterized by mutated (constitutively active) and over-expressed KIT, respectively. Since tyrosine phosphorylation regulates the enzymatic activity and oncogenic function of KIT protein we hypothesized that this kinase could be a substrate of PTPROt and that expression of PTPROt would be critical to maintain control of its activity. Indeed, using in vitro substrate-trapping assay we demonstrated that KIT is a direct substrate of PTPROt. Further, in vivo studies conducted by co-transfecting KITD816V and PTPROt (wild type or catalytic site mutant) in H293T cells showed that phosphorylation of KIT at Y719, a read-out for KIT activity, was reduced when KIT was co-expressed with PTPROt-WT but not with vector control or catalytic site mutant of PTPROt. These observations suggest that suppression of PTPROt in CBF AML with over-expressed or mutated KIT could contribute to the leukemogeneic function of KIT. Given that the epigenetic suppression of PTPROt can be reversed by hypomethylating agent decitabine, it is possible that combination of decitabine and tyrosine kinase inhibitors with or without chemotherapy may represent a novel therapeutic approach in CBF AML. [Supported by grant CA101956] Disclosures: No relevant conflicts of interest to declare.

Protein Tyrosine Phosphatase Type-1 (PTPN1) Is Frequently Mutated In Primary Mediastinal B Cell Lymphoma and Hodgkin Lymphoma

Blood ◽  
2013 ◽  
Vol 122 (21) ◽  
pp. 242-242
Author(s):  
Jay Gunawardana ◽  
Fong Chun Chan ◽  
Adele Telenius ◽  
Bruce W. Woolcock ◽  
Robert Kridel ◽  
...  
Keyword(s):  
Cell Lines ◽  
Protein Tyrosine Phosphatase ◽  
Cell Lymphoma ◽  
Tyrosine Phosphatase ◽  
B Cell Lymphoma ◽  
Clinical Samples ◽  
Hek 293 ◽  
Empty Vector Control ◽  
Empty Vector ◽  
293 Cells

Abstract Introduction Hodgkin Lymphoma (HL) accounts for 11% of all lymphomas and despite being one of the most curable lymphomas, 20% of HL patients still ultimately die of their disease. Similarly, a proportion of cases of primary mediastinal B cell lymphoma (PMBCL) have refractory disease or early relapse and frequently fail second-line therapy. Development of more targeted therapeutic approaches is impeded by the lack of knowledge about the mutational landscape in the cancer genomes of these lymphomas. PTPN1 is a protein tyrosine phosphatase gene that encodes the protein, PTP1B. PTP1B dephosphorylates tyrosine residues on many activated kinases to maintain cellular homeostasis. As overactive receptor kinases are critical oncogenic events in cancer, we hypothesized that constitutively active Janus kinase-Signal transducer and activation of transcription (JAK-STAT) observed in HL and PMBCL are in part due to a mutated PTPN1 gene with an impaired functional ability to dephosphorylate this constitutive signaling pathway. Methods and samples Biopsies at the time of primary diagnosis were obtained for 49 PMBCL and 30 HL patients from the British Columbia Cancer Agency, Arizona Lymphoma Repository and the Hôpital Henri Mondor Pathology Department. DNA from PMBCL samples, microdissected Hodgkin Reed Sternberg (HRS) cells and 12 lymphoma-derived cell lines were extracted for PTPN1 exonic PCR amplification (nested PCR was used for HRS cell DNA) and Sanger sequencing. PTPN1 was silenced in a HL cell line (KMH2) by lentiviral transduction of a vector expressing shRNA and confirmed by quantitative real time (qRT) PCR. Wild type and mutant PTPN1 cDNA were cloned into the mammalian expression vector pcDNA 3.1 and expressed in HEK-293 cells. Protein expression of clinical samples, silenced and expressed cells were analyzed by immunohistochemistry and western blotting. Comparisons between groups were performed using two-sample student t tests. Results After exclusion of reported single nucleotide polymorphisms (SNPs) and silent mutations, 16 PTPN1 coding sequence mutations were found in our PMBCL cohort, corresponding to 14 mutations (29%) in clinical samples and 2 in PMBCL-dervied cell lines. Twelve additional mutations were discovered in our HL cohort, corresponding to 6 mutations (20%) in HRS cell samples and another 6 in HL-derived cell lines. In total, 14 (54%) missense, 4 (15%) frameshift, 3 (12%) single amino acid deletions, 4 (15%) nonsense mutations, and 1 (4%) promoter mutation were observed. Eight of these mutations were confirmed as somatic by sequencing of matched constitutional DNA. Silencing of PTPN1 resulted in hyperphosphorylation of JAK1, JAK2, STAT3, STAT5, STAT6 and up-regulation of the oncogenes, MYC and BCL6. Ectopic expression of nonsense and missense PTPN1 mutants in HEK-293 cells led to sustained phosphorylation of STAT6 in comparison to the empty vector control (densitometric values Q9* 0.5 vs. 1.0, R156* 0.7 vs. 1.0, M74L 0.4 vs. 1.0 and M282L 0.8 vs. 1.0). Furthermore, no phosphatase activity was observed for the nonsense mutants and moderate phosphatase activity for the missense mutants using a tyrosine phosphatase-specific substrate (fold change Q9* 2.0, R156* 1.9, M74L 46.7, M282L 46.0 and WT 58.3, compared to empty vector control). Immunohistochemical analysis showed that PTPN1 mutations correspond to decreased protein expression in PMBCL (p=0.03). Discussion PTPN1 is recurrently mutated in PMBCL and HL contributing to constitutive JAK-STAT signaling and oncogene dysregulation. These data suggest PTPN1 mutations as novel driver alterations in these lymphomas and might provide a novel, rational therapeutic target for treating HL and PMBCL patients. Disclosures: Savage: Eli-Lilly: Consultancy. Connors:F Hoffmann-La Roche: Research Funding; Roche Canada: Research Funding.

The Receptor Protein Tyrosine Phosphatase, PTP-RO, Is Upregulated During Megakaryocyte Differentiation and Is Associated With the c-Kit Receptor

Blood ◽  
1999 ◽  
Vol 94 (2) ◽  
pp. 539-549
Author(s):  
Yoshitaka Taniguchi ◽  
Roanna London ◽  
Karin Schinkmann ◽  
Shuxian Jiang ◽  
Hava Avraham
Keyword(s):  
Bone Marrow ◽  
Tyrosine Kinase ◽  
Cell Lines ◽  
Protein Tyrosine Phosphatase ◽  
Tyrosine Phosphatase ◽  
Tyrosine Kinase Receptor ◽  
Transfected Cells ◽  
Kit Ligand ◽  
Kit Receptor ◽  
Megakaryocytic Cell

We have recently isolated a cDNA encoding a novel human receptor-type tyrosine phosphatase, termed PTP-RO (for a protein tyrosine phosphatase receptor omicron), from 5-fluorouracil–treated murine bone marrow cells. PTP-RO is a human homologue of murine PTPλ and is related to the homotypically adhering κ and μ receptor-type tyrosine phosphatases. PTP-RO is expressed in human megakaryocytic cell lines, primary bone marrow megakaryocytes, and stem cells. PTP-RO mRNA and protein expression are upregulated upon phorbol 12-myristate 13-acetate (PMA) treatment of the megakaryocytic cell lines CMS, CMK, and Dami. To elucidate the function of PTP-RO in megakaryocytic cells and its potential involvement in the stem cell factor (SCF)/c-Kit receptor pathway, COS-7 and 293 cells were cotransfected with the cDNAs of both the c-Kit tyrosine kinase receptor and PTP-RO. PTP-RO was found to be associated with the c-Kit receptor in these transfected cells and the SCF/Kit ligand induced a rapid tyrosine phosphorylation of PTP-RO. Interestingly, these transfected cells demonstrated a decrease in their proliferative response to the SCF/Kit ligand. In addition, we assessed the association of PTP-RO with c-Kit in vivo. The results demonstrated that PTP-RO associates with c-Kit but not with the tyrosine kinase receptor FGF-R and that PTP-RO is tyrosine-phosphorylated after SCF stimulation of Mo7e and CMK cells. Antisense oligonucleotides directed against PTP-RO mRNA sequences significantly inhibited megakaryocyte progenitor proliferation. Therefore, these data show that the novel tyrosine kinase phosphatase PTP-RO is involved in megakaryocytopoiesis and that its function is mediated by the SCF/c-Kit pathway.

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