Assessment of lectinic activity potentials in extracts of some tropical Euphorbiaceace

Lectins bind a variety of cells having cell surface glycoprotein or glycolipid, such as erythrocytes, leukemic cells, yeast and several types of bacteria. Several specificity groups have been identified such as mannose, galactose, N-acetyl glucoseamine, N-acetyl galactoseamine, L-fucose and N-acetyl neuraminic acid. The presence of two or more binding sites for each Lectin molecule allows the agglutination of many cell type. Sixteen (16) species of some tropical Euphorbiaceae plants were assessed for the presence of Lectins. The leaves of Acalypha torta, Acalypha wiskesiana, Acalypha hispida, Codiaeum variegatum, Euphorbia milli, Euphorbia pulcherima, Jatropha curcas and Jatropha gossypifola; the seeds of Croton tiglium, Ricinus comminus and Tetracarpidium conophorum; the stem of Euphorbia tirucalli and the tubers of Manihot esculenta (Cassava, vitamin A variety), Manihot esculenta (cassava, NR 8082 variety), Manihot esculenta (Cassava, TMX 419 variety), Manihot esculenta (Cassava, TMX 4(2) 1425 variety) were used for sourcing the Lectins. A. torta, A. wiskesiana, C. variegatum, C. tiglium, E. milli, E. pulcherima, E. tirucalli, J. curcas, J. gossypifola, R. comminus and T. conophorum agglutinated pooled washed human ABO cells in saline (direct haemagglutination) while A. hispida and the four varieties of M. esculenta showed no agglutination reaction. E. pulcherima showed specificity for B cells only while E. tirucalli showed specificity for O cells only, hence could be rightly indicated by referring to them as anti-B Ep and anti-H Et Lectins respectively (where Ep=Euphorbia pulcherima and Et= Euphorbia tirucalli). However A. torta and T. conophorum cross-reacted with pooled washed ABO cells in differing strengths and when standardized, showed that A. torta at a titre of 16 reacted specifically with O cells and T. conophorum at a titre of 128 reacted specifically with B cells. Based on this, these Lectins could be indicated as anti-H At and anti-B Tc respectively (Where At= Acalypha torta and Tc= Tetracarpidium conophorum). The protein content of the crude extracts of the sixteen (16) species were also assayed using Biuret protein assay method and the results revealed that there are no relation or association between the quantity of protein content and agglutination patterns of the extracts. This research has therefore succeeded in revealing presence of Lectinic properties in extracts of some tropical Euphorbiaceae.

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Hyaluronate-CD44 Interactions Can Induce Murine B-Cell Activation

Blood ◽

10.1182/blood.v89.8.2901 ◽

1997 ◽

Vol 89 (8) ◽

pp. 2901-2908 ◽

Cited By ~ 71

Author(s):

Asimah Rafi ◽

Mitzi Nagarkatti ◽

Prakash S. Nagarkatti

Keyword(s):

T Cells ◽

B Cells ◽

B Cell ◽

Cell Activation ◽

Critical Role ◽

Surface Glycoprotein ◽

B Cell Differentiation ◽

B Cell Activation ◽

Cell Surface Glycoprotein ◽

Immunodeficient Mice

Abstract CD44 is a widely distributed cell surface glycoprotein whose principal ligand has been identified as hyaluronic acid (HA), a major component of the extracellular matrix (ECM). Recent studies have demonstrated that activation through CD44 leads to induction of effector function in T cells and macrophages. In the current study, we investigated whether HA or monoclonal antibodies (MoAbs) against CD44 would induce a proliferative response in mouse lymphocytes. Spleen cells from normal and nude, but not severe combined immunodeficient mice, exhibited strong proliferative responsiveness to stimulation with soluble HA or anti-CD44 MoAbs. Furthermore, purified B cells, but not T cells, were found to respond to HA. HA was unable to stimulate T cells even in the presence of antigen presenting cells (APC) and was unable to act as a costimulus in the presence of mitogenic or submitogenic concentrations of anti-CD3 MoAbs. In contrast, stimulation of B cells with HA in vitro, led to B-cell differentiation as measured by production of IgM antibodies in addition to increased expression of CD44 and decreased levels of CD45R. The fact that the B cells were responding directly to HA through its binding to CD44 and not to any contaminants or endotoxins was demonstrated by the fact that F(ab)2 fragments of anti-CD44 MoAbs or soluble CD44 fusion proteins could significantly inhibit the HA-induced proliferation of B cells. Also, HA-induced proliferation of B cells was not affected by the addition of polymixin B, and B cells from lipopolysaccharide (LPS)-unresponsive C3H/HeJ strain responded strongly to stimulation with HA. Furthermore, HA, but not chondroitin-sulfate, another major component of the ECM, induced B-cell activation. It was also noted that injection of HA intraperitoneally, triggered splenic B cell proliferation in vivo. Together, the current study demonstrates that interaction between HA and CD44 can regulate murine B-cell effector functions and that such interactions may play a critical role during normal or autoimmune responsiveness of B cells.

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A Strong Expression of CD44-6v Correlates With Shorter Survival of Patients With Acute Myeloid Leukemia

Blood ◽

10.1182/blood.v91.9.3401.3401_3401_3413 ◽

1998 ◽

Vol 91 (9) ◽

pp. 3401-3413 ◽

Cited By ~ 4

Author(s):

S. Legras ◽

U. Günthert ◽

R. Stauder ◽

F. Curt ◽

S. Oliferenko ◽

...

Keyword(s):

Acute Myeloid Leukemia ◽

Protein Expression ◽

Myeloid Leukemia ◽

Surface Glycoprotein ◽

Leukemic Cells ◽

Cell Surface Glycoprotein ◽

Variant Isoforms ◽

Cd34 Cells ◽

First Time ◽

Acute Myeloid

CD44 is a ubiquitous cell-surface glycoprotein that displays many variant isoforms (CD44v) generated by alternative splicing of exons 2v to 10v. The expression of variant isoforms is highly restricted and correlated with specific processes, such as leukocyte activation and malignant transformation. We have herein studied CD44v expression in acute myeloid leukemia (AML) and, for comparison, in normal myelopoiesis. Protein expression of total CD44 and of CD44-3v, -6v, and -9v isoforms has been measured using specific monoclonal antibodies and flow cytometry. The composition of variant exon transcripts has been analyzed by semi-quantitative reverse transcriptase-polymerase chain reaction followed by Southern hybridization with exon-specific probes. Our data show that (1) CD44-6v isoforms are expressed on 12.0% ± 2.5% of normal CD34+ cells; this expression is sharply upregulated through monopoiesis and, inversely, downregulated during granulopoiesis. Also, CD44-3v and CD44-9v isoforms are detected on 10% and 14% of normal monocytes, respectively. (2) Sixty-nine from a total of 95 AML patients display a variable proportion (range, 5% to 80%) of CD44-6v+ leukemic cells. (3) A shorter overall survival characterizes the group of AML patients displaying more than 20% of CD44-6v+ leukemic cells (8 months v 18 months, P < .02). These data suggest, for the first time, that the protein expression of CD44-6v containing isoforms may serve as a new prognostic factor in AML.

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CD5 is a potential selecting ligand for B cell surface immunoglobulin framework region sequences.

Journal of Experimental Medicine ◽

10.1084/jem.184.4.1279 ◽

1996 ◽

Vol 184 (4) ◽

pp. 1279-1284 ◽

Cited By ~ 60

Author(s):

R Pospisil ◽

M G Fitts ◽

R G Mage

Keyword(s):

B Cells ◽

Cell Surface ◽

B Cell ◽

B Lymphocyte ◽

Surface Glycoprotein ◽

Cell Surface Glycoprotein ◽

Surface Immunoglobulins ◽

B Lymphocyte Development ◽

Framework Region ◽

Rabbit Appendix

In rabbits nearly all B lymphocytes express the glycoprotein CD5, in contrast to mice and humans, where only a small proportion of B cells express this molecule (Raman, C., and K.L. Knight. 1992. J. Immunol. 149:3858-3864). CD5+ B cells appear to develop early in ontogeny and be maintained throughout life by self-renewal. The function of CD5 on B cells is still unknown. We showed earlier that "positive" selection occurs during B lymphocyte development in the rabbit appendix. This selection favors B cell expressing surface immunoglobulins with VHa2 structures in the first and third framework regions (Pospisil, R., G.O. Young-Cooper, and R.G. Mage. 1995. Proc. Natl. Acad. Sci. USA. 92:6961-6965). Here we report that F(ab')2 fragments, especially those bearing VHa2 framework region determinants, specifically interact with the B cell-surface glycoprotein CD5. This interaction can be inhibited by anti-CD5 antibodies. Furthermore, immobilized F(ab')2 fragments selectively bind CD5 molecules in appendix cell lysates. Interactions of VH framework region structures with CD5 may affect maintenance and selective expansion of particular B cells and thus contribute to autostimulatory growth of autoimmune or transformed cells.

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CD44-stimulated human B cells express transcripts specifically involved in immunomodulation and inflammation as analyzed by DNA microarrays

Blood ◽

10.1182/blood-2002-06-1837 ◽

2003 ◽

Vol 101 (6) ◽

pp. 2307-2313 ◽

Cited By ~ 16

Author(s):

Carl-Magnus Högerkorp ◽

Sven Bilke ◽

Thomas Breslin ◽

Sigurdur Ingvarsson ◽

Carl A. K. Borrebaeck

Keyword(s):

B Cells ◽

Dna Microarrays ◽

Lymphocyte Activation ◽

Cell Receptor ◽

Surface Glycoprotein ◽

Data Sets ◽

Cell Surface Glycoprotein ◽

Human B Cells ◽

Analysis Scheme

A number of studies have implicated a role for the cell surface glycoprotein CD44 in several biologic events, such as lymphopoiesis, homing, lymphocyte activation, and apoptosis. We have earlier reported that signaling via CD44 on naive B cells in addition to B-cell receptor (BCR) and CD40 engagement generated a germinal center–like phenotype. To further characterize the global role of CD44 in B differentiation, we examined the expression profile of human B cells cultured in vitro in the presence or absence of CD44 ligation, together with anti-immunoglobulin (anti-Ig) and anti-CD40 antibodies. The data sets derived from DNA microarrays were analyzed using a novel statistical analysis scheme created to retrieve the most likely expression pattern of CD44 ligation. Our results show that genes such as interleukin-6 (IL-6), IL-1α, and β2-adrenergic receptor (β2-AR) were specifically up-regulated by CD44 ligation, suggesting a novel role for CD44 in immunoregulation and inflammation.

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A6 Peptide Is Selectively Cytotoxic For Chronic Lymphocytic Leukemia Cells

Blood ◽

10.1182/blood.v122.21.5303.5303 ◽

2013 ◽

Vol 122 (21) ◽

pp. 5303-5303

Author(s):

Suping Zhang ◽

Hsien Lai ◽

Grace Liu ◽

Laura Rassenti ◽

Michael Y. Choi ◽

...

Keyword(s):

Hyaluronic Acid ◽

B Cells ◽

Chronic Lymphocytic Leukemia ◽

Lymphocytic Leukemia ◽

Surface Glycoprotein ◽

Leukemia Cells ◽

Dependent Manner ◽

Cell Surface Glycoprotein

Abstract Chronic lymphocytic leukemia (CLL) cells express high levels of CD44, a cell-surface glycoprotein receptor for hyaluronic acid (HA). We found that a mAb specific for CD44 was directly cytotoxic for leukemia B cells, but had little effect on normal B cells. Moreover, this anti-CD44 mAb could induce CLL cells that expressed the zeta-associated protein of 70 kDa (ZAP-70) to undergo caspase-dependent apoptosis, independent of complement or cytotoxic effector cells (Proc Natl Acad Sci, USA 2013, PMID: 23530247). The cytotoxic effect of this mAb was not mitigated when the CLL cells were co-cultured with mesenchymal stromal cells (MSCs) or hyaluronic acid or when they were stimulated via ligation of the B-cell receptor with anti-µ. A6 (Angstrom Pharmaceuticals) is an 8-amino acid peptide that has marked homology with a linear sequence of CD44. A6 can bind CD44 within a region of the ligand-binding domain, leading to inhibition of the migration and metastatic potential of CD44-expressing cancer cells in vitro and in vivo (Mol Cancer Ther, 2011 PMID: 21885863). We evaluated the cytotoxic activity of A6 against primary leukemia cells of patients with CLL (n = 22). We found that A6 peptide also was directly cytotoxic for CLL cells isolated from different patients in a dose-dependent manner at concentrations that may be achieved in vivo. The A6 peptide appeared less cytotoxic for CLL cells than the intact anti-CD44 mAb, but still had greater direct cytotoxicity for CLL cells that expressed ZAP-70 than for CLL cells that were ZAP-70 negative. Furthermore, the A6 peptide had negligible effect on the viability of lymphocytes isolated from the blood of healthy donors (n = 3). Because clinical studies have found the A6 peptide to be well-tolerated and without dose-limiting toxicity in patients with solid tumors who have been treated to date (N = 40), a clinical study is planned to evaluate the safety and activity of the A6 peptide in the treatment of patients with CLL. Disclosures: Howell: Angstrom Phamaceuticals: Membership on an entity’s Board of Directors or advisory committees. Finlayson:Angstrom Phamaceuticals: Employment.

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Monoclonal antibody YB5.B8 identifies the human c-kit protein product

Blood ◽

10.1182/blood.v77.9.1876.1876 ◽

1991 ◽

Vol 77 (9) ◽

pp. 1876-1883 ◽

Cited By ~ 96

Author(s):

NB Lerner ◽

KH Nocka ◽

SR Cole ◽

FH Qiu ◽

A Strife ◽

...

Keyword(s):

Monoclonal Antibody ◽

Mast Cells ◽

Cell Surface ◽

Bone Marrow Cells ◽

Protein Product ◽

Surface Glycoprotein ◽

Leukemic Cells ◽

Acute Myelocytic Leukemia ◽

Erythroid Progenitors ◽

Cell Surface Glycoprotein

Abstract The c-kit proto-oncogene encodes a 145- to 160-Kd transmembrane tyrosine kinase, which is a member of the platelet-derived growth factor receptor family and is allelic with the murine white spotting locus (W). W mutations affect several aspects of hematopoiesis, most notably erythroid progenitors and mast cells. A monoclonal antibody, YB5.B8, had been raised against the leukemic blasts of a patient with M1-type acute myelocytic leukemia (AML) and it precipitates a 150-Kd cell surface glycoprotein from leukemic cells. The YB5.B8 epitope is expressed on mast cells, on up to 3% of normal mononuclear bone marrow cells, and it identifies a sub-group of AML patients with a poor prognosis. In view of similarities noted between the cell surface antigen identified by YB5.B8 and the c-kit protein product, we performed experiments to determine whether they are identical. c-kit RNA expression in the cell lines HEL (human erythroleukemia) and A172 (glioblastoma) was shown to parallel the expression of the YB5.B8 epitope in these lines as measured by flow cytometry. Immunoprecipitation analysis with anti-kit serum and YB5.B8 antibody indicated that the two antibodies identified proteins of identical size in HEL (155 Kd) and A172 (145 Kd) cells, and sequential immunoprecipitations with the kit and the YB5.B8 antibodies demonstrated that the two antibodies recognize the same molecule. The proteins identified by both the anti-kit and YB5.B8 antibodies displayed in vitro autophosphorylation activity in immune complex kinase assays. In addition, YB5.B8 was able to inhibit the binding of the kit ligand to HEL cells. These studies provide evidence that the YB5.B8 antigen and the c-kit protein product are identical and raise certain hypotheses regarding the role of c-kit in AML.

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Identification of a cell-surface glycoprotein mediating cell adhesion in EBV-immortalized normal B cells

International Journal of Cancer ◽

10.1002/ijc.2910380414 ◽

1986 ◽

Vol 38 (4) ◽

pp. 539-547 ◽

Cited By ~ 28

Author(s):

Manuel Patarroyo ◽

Patrick G. Beatty ◽

Kenneth Nilsson ◽

Carl G. Gahmberg

Keyword(s):

Cell Adhesion ◽

B Cells ◽

Cell Surface ◽

Surface Glycoprotein ◽

Cell Surface Glycoprotein ◽

A Cell

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TIM-3, a Leukemia Stem Cell Marker, Plays a Role In Leukemic Transformation Through Autocrine Stimulatory Signaling By Its Ligand, Galectin-9

Blood ◽

10.1182/blood.v122.21.4196.4196 ◽

2013 ◽

Vol 122 (21) ◽

pp. 4196-4196

Author(s):

Yoshikane Kikushige ◽

Junichiro Yuda ◽

Takahiro Shima ◽

Toshihiro Miyamoto ◽

Koichi Akashi

Keyword(s):

Stem Cells ◽

Stem Cell ◽

Myeloid Leukemia ◽

Transmembrane Domain ◽

Cytoplasmic Tail ◽

Surface Glycoprotein ◽

Leukemic Cells ◽

Stem Cell Marker ◽

Cell Surface Glycoprotein ◽

Hematopoietic Stem

Abstract Acute myeloid leukemia (AML) originates from self-renewing leukemic stem cells (LSCs), an ultimate therapeutic target for AML. We have reported that the T-cell immunoglobulin mucin-3 (TIM-3) is expressed on LSCs in most types of AML but not on normal hematopoietic stem cells (HSCs) (Kikushige et al, Cell Stem Cell, 2010). We extended the analysis of TIM-3 expression into various types of human hematological malignancies, and found that human TIM-3 is expressed in the vast majority of CD34+CD38- LSCs of human myeloid malignancies including chronic myeloid leukemia, chronic myelomonocytic leukemia and myelodysplastic syndromes (MDS). Although CD34+CD38- normal bone marrow stem cells do not express TIM-3, TIM-3 is expressed in the CD34+CD38- population in MDS, and is further up-regulated with progression into leukemia. The average percentages of TIM-3+ cells in the CD34+CD38- population was 7.8% in RCMD (n=10), 19.2% in RAEB-1 (n=10), 84.0% in RAEB-2 (n=10) and 92.2% in overt AML (n=10). The close association of TIM-3 expression with transformation into AML led us to hypothesize that TIM-3 itself has a function in AML stem cell development. TIM-3 is a type 1 cell-surface glycoprotein and has a structure that includes an N-terminal immunoglobulin variable domain followed by a mucin domain, a transmembrane domain and a cytoplasmic tail. Tyrosine residues are clustered in the cytoplasmic tail, suggesting that TIM-3 can induce signal transduction in TIM-3+ AML cells. To understand the function of TIM-3, we investigated the interaction between TIM-3 and its ligand galectin-9 in AML LSCs. We found that AML patients showed significantly higher serum galectin-9 concentration than healthy individuals (healthy controls: 18.3+4.3 pg/ml, AML patients: 139.1+33.4 pg/ml, P<0.05). Unexpectedly, we found that leukemic cells expressed a high level of galectin-9 protein, as compared to other hematopoietic cells including T cells, B cells and monocytes. Using KASUMI-3 (TIM-3+ AML cell line) and primary AML samples, we confirmed that AML cells could secrete galectin-9 after TLR stimulation in vitro. Furthermore, microarray analysis demonstrated that TIM-3 stimulation by the physiological concentration of galectin-9 induced significant gene expression changes toward pro-survival axis including up-regulation of MCL-1, the important survival factor for HSCs and LSCs. These results collectively suggest that AML cells can produce and secrete galectin-9, and galectin-9 can bind and stimulate TIM-3-expressing AML cells including LSCs in an autocrine manner to support their survival or leukemia progression. Disclosures: Miyamoto: Kyushu University Hospital: Employment.

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A Strong Expression of CD44-6v Correlates With Shorter Survival of Patients With Acute Myeloid Leukemia

Blood ◽

10.1182/blood.v91.9.3401 ◽

1998 ◽

Vol 91 (9) ◽

pp. 3401-3413 ◽

Cited By ~ 86

Author(s):

S. Legras ◽

U. Günthert ◽

R. Stauder ◽

F. Curt ◽

S. Oliferenko ◽

...

Keyword(s):

Acute Myeloid Leukemia ◽

Protein Expression ◽

Myeloid Leukemia ◽

Surface Glycoprotein ◽

Leukemic Cells ◽

Cell Surface Glycoprotein ◽

Variant Isoforms ◽

Cd34 Cells ◽

First Time ◽

Acute Myeloid

Abstract CD44 is a ubiquitous cell-surface glycoprotein that displays many variant isoforms (CD44v) generated by alternative splicing of exons 2v to 10v. The expression of variant isoforms is highly restricted and correlated with specific processes, such as leukocyte activation and malignant transformation. We have herein studied CD44v expression in acute myeloid leukemia (AML) and, for comparison, in normal myelopoiesis. Protein expression of total CD44 and of CD44-3v, -6v, and -9v isoforms has been measured using specific monoclonal antibodies and flow cytometry. The composition of variant exon transcripts has been analyzed by semi-quantitative reverse transcriptase-polymerase chain reaction followed by Southern hybridization with exon-specific probes. Our data show that (1) CD44-6v isoforms are expressed on 12.0% ± 2.5% of normal CD34+ cells; this expression is sharply upregulated through monopoiesis and, inversely, downregulated during granulopoiesis. Also, CD44-3v and CD44-9v isoforms are detected on 10% and 14% of normal monocytes, respectively. (2) Sixty-nine from a total of 95 AML patients display a variable proportion (range, 5% to 80%) of CD44-6v+ leukemic cells. (3) A shorter overall survival characterizes the group of AML patients displaying more than 20% of CD44-6v+ leukemic cells (8 months v 18 months, P < .02). These data suggest, for the first time, that the protein expression of CD44-6v containing isoforms may serve as a new prognostic factor in AML.

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Monoclonal antibody YB5.B8 identifies the human c-kit protein product

Blood ◽

10.1182/blood.v77.9.1876.bloodjournal7791876 ◽

1991 ◽

Vol 77 (9) ◽

pp. 1876-1883 ◽

Cited By ~ 1

Author(s):

NB Lerner ◽

KH Nocka ◽

SR Cole ◽

FH Qiu ◽

A Strife ◽

...

Keyword(s):

Monoclonal Antibody ◽

Mast Cells ◽

Cell Surface ◽

Bone Marrow Cells ◽

Protein Product ◽

Surface Glycoprotein ◽

Leukemic Cells ◽

Acute Myelocytic Leukemia ◽

Erythroid Progenitors ◽

Cell Surface Glycoprotein

The c-kit proto-oncogene encodes a 145- to 160-Kd transmembrane tyrosine kinase, which is a member of the platelet-derived growth factor receptor family and is allelic with the murine white spotting locus (W). W mutations affect several aspects of hematopoiesis, most notably erythroid progenitors and mast cells. A monoclonal antibody, YB5.B8, had been raised against the leukemic blasts of a patient with M1-type acute myelocytic leukemia (AML) and it precipitates a 150-Kd cell surface glycoprotein from leukemic cells. The YB5.B8 epitope is expressed on mast cells, on up to 3% of normal mononuclear bone marrow cells, and it identifies a sub-group of AML patients with a poor prognosis. In view of similarities noted between the cell surface antigen identified by YB5.B8 and the c-kit protein product, we performed experiments to determine whether they are identical. c-kit RNA expression in the cell lines HEL (human erythroleukemia) and A172 (glioblastoma) was shown to parallel the expression of the YB5.B8 epitope in these lines as measured by flow cytometry. Immunoprecipitation analysis with anti-kit serum and YB5.B8 antibody indicated that the two antibodies identified proteins of identical size in HEL (155 Kd) and A172 (145 Kd) cells, and sequential immunoprecipitations with the kit and the YB5.B8 antibodies demonstrated that the two antibodies recognize the same molecule. The proteins identified by both the anti-kit and YB5.B8 antibodies displayed in vitro autophosphorylation activity in immune complex kinase assays. In addition, YB5.B8 was able to inhibit the binding of the kit ligand to HEL cells. These studies provide evidence that the YB5.B8 antigen and the c-kit protein product are identical and raise certain hypotheses regarding the role of c-kit in AML.

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