scholarly journals An immunotoxin with therapeutic potential in T cell leukemia: WT1-ricin A

Blood ◽  
1984 ◽  
Vol 63 (5) ◽  
pp. 1178-1185 ◽  
Author(s):  
CD Myers ◽  
PE Thorpe ◽  
WC Ross ◽  
AJ Cumber ◽  
FE Katz ◽  
...  
Keyword(s):  
T Cell ◽  
Ammonium Chloride ◽  
Therapeutic Potential ◽  
Autologous Transplantation ◽  
Lymphocytic Leukemia ◽  
Normal Human ◽  
A Chain ◽  
Density Treatment ◽  
Normal Human Bone Marrow ◽  
Ricin A

Abstract A conjugate of the monoclonal antibody WT1 and ricin A-chain was studied for its suitability for purging marrow of leukemic T cells for autologous transplantation in T cell acute lymphocytic leukemia (T- ALL). The conjugate was powerfully cytotoxic to the human T-ALL cell line, GH1, which expresses the WT1 antigen at a high density. Treatment of the cells with the conjugate at 10(-11) M reduced their rate of protein synthesis by 50%, and the inclusion of 6 mM ammonium chloride in the cultures enhanced the potency of cytotoxic effect by 10–100- fold. Clonogenic assays indicated that less than 0.1% of GH1 cells survived 3-hr exposure to the conjugate in ammonium chloride. WT1 alone did not react with multipotent (CFU-GEMM) hematopoietic progenitors in normal human bone marrow, as measured by fluorescence-activated cell sorting. Under conditions giving maximal killing of GH1 cells, there was no toxicity to multipotential progenitors in normal human marrow.

scholarly journals An immunotoxin with therapeutic potential in T cell leukemia: WT1-ricin A

Blood ◽  
1984 ◽  
Vol 63 (5) ◽  
pp. 1178-1185
Author(s):  
CD Myers ◽  
PE Thorpe ◽  
WC Ross ◽  
AJ Cumber ◽  
FE Katz ◽  
...  
Keyword(s):  
T Cell ◽  
Ammonium Chloride ◽  
Therapeutic Potential ◽  
Autologous Transplantation ◽  
Lymphocytic Leukemia ◽  
Normal Human ◽  
A Chain ◽  
Density Treatment ◽  
Normal Human Bone Marrow ◽  
Ricin A

A conjugate of the monoclonal antibody WT1 and ricin A-chain was studied for its suitability for purging marrow of leukemic T cells for autologous transplantation in T cell acute lymphocytic leukemia (T- ALL). The conjugate was powerfully cytotoxic to the human T-ALL cell line, GH1, which expresses the WT1 antigen at a high density. Treatment of the cells with the conjugate at 10(-11) M reduced their rate of protein synthesis by 50%, and the inclusion of 6 mM ammonium chloride in the cultures enhanced the potency of cytotoxic effect by 10–100- fold. Clonogenic assays indicated that less than 0.1% of GH1 cells survived 3-hr exposure to the conjugate in ammonium chloride. WT1 alone did not react with multipotent (CFU-GEMM) hematopoietic progenitors in normal human bone marrow, as measured by fluorescence-activated cell sorting. Under conditions giving maximal killing of GH1 cells, there was no toxicity to multipotential progenitors in normal human marrow.

scholarly journals Optimal elimination of leukemic T cells from human bone marrow with T101-ricin A-chain immunotoxin

Blood ◽  
1985 ◽  
Vol 65 (2) ◽  
pp. 289-297 ◽  
Author(s):  
P Casellas ◽  
X Canat ◽  
AA Fauser ◽  
O Gros ◽  
G Laurent ◽  
...  
Keyword(s):  
Bone Marrow ◽  
T Cells ◽  
T Cell ◽  
Autologous Transplantation ◽  
Leukemic Cells ◽  
Ricin A Chain ◽  
Hematopoietic Stem ◽  
Human T Cell ◽  
A Chain ◽  
Ricin A

Abstract In view of bone marrow purging before autologous transplantation in T cell malignancies, an anti-human T cell immunotoxin (IT) has been prepared by coupling ricin A-chain to the monoclonal antibody T101 that binds the T1 differentiation antigen expressed by T lymphocytes as well as by T cell-derived hematologic malignancies. Using a sensitive and reliable clonogenic assay, optimal conditions were defined for the elimination of clonogenic human T leukemic cells among bone marrow cells. Maximal cytoreduction was obtained with IT at a dose of 2 micrograms/mL in the presence of 10 mmol/L NH4Cl. This treatment led to the reduction of more than six orders of magnitude of T101-positive clonogenic leukemic cells, with no harm to T101-negative cells. Moreover, we observed no toxicity of IT to human hematopoietic stem cells (CFU-GEMMT) derived from bone marrow of healthy volunteers. Thus, pretreatment of bone marrow samples with IT plus NH4Cl offers a safe, simple, reliable, and highly efficient means to eliminate undesirable leukemic T cells from the graft.

scholarly journals Optimal elimination of leukemic T cells from human bone marrow with T101-ricin A-chain immunotoxin

Blood ◽  
1985 ◽  
Vol 65 (2) ◽  
pp. 289-297
Author(s):  
P Casellas ◽  
X Canat ◽  
AA Fauser ◽  
O Gros ◽  
G Laurent ◽  
...  
Keyword(s):  
Bone Marrow ◽  
T Cells ◽  
T Cell ◽  
Autologous Transplantation ◽  
Leukemic Cells ◽  
Ricin A Chain ◽  
Hematopoietic Stem ◽  
Human T Cell ◽  
A Chain ◽  
Ricin A

In view of bone marrow purging before autologous transplantation in T cell malignancies, an anti-human T cell immunotoxin (IT) has been prepared by coupling ricin A-chain to the monoclonal antibody T101 that binds the T1 differentiation antigen expressed by T lymphocytes as well as by T cell-derived hematologic malignancies. Using a sensitive and reliable clonogenic assay, optimal conditions were defined for the elimination of clonogenic human T leukemic cells among bone marrow cells. Maximal cytoreduction was obtained with IT at a dose of 2 micrograms/mL in the presence of 10 mmol/L NH4Cl. This treatment led to the reduction of more than six orders of magnitude of T101-positive clonogenic leukemic cells, with no harm to T101-negative cells. Moreover, we observed no toxicity of IT to human hematopoietic stem cells (CFU-GEMMT) derived from bone marrow of healthy volunteers. Thus, pretreatment of bone marrow samples with IT plus NH4Cl offers a safe, simple, reliable, and highly efficient means to eliminate undesirable leukemic T cells from the graft.

scholarly journals Evolution of a CD3+/CD+α/ βT-Cell Receptor+Mature T-Cell Clone from CD3-CD7+Sorted Human Bone Marrow Cells

1993 ◽  
Vol 3 (3) ◽  
pp. 197-210 ◽  
Author(s):  
Heike Pohla ◽  
Medi Adibzadeh ◽  
Hans-Jörg Bühring ◽  
Petra Siegels-Hübenthal ◽  
Thomas Deikeler ◽  
...  
Keyword(s):  
Bone Marrow ◽  
T Cell ◽  
Human Bone ◽  
Human Bone Marrow ◽  
Target Cells ◽  
Gm Csf ◽  
T Cell Clone ◽  
Normal Human ◽  
Normal Human Bone Marrow

In order to study extrathymic differentiationin vitro, CD7+CD3-lymphocytes were sorted from normal human bone marrow and cultured under conditions of limiting dilution together with irradiated pooled allogeneic peripheral blood mononuclear cells (PBMC) and phytohemagglutinin (PHA) in the presence of 1000 U/ml of interleukin-2 (IL-2). One clone was obtained that failed to react with monoclonal antibody (mAb) TCRδ1 (TCRγ/δ-specific) or WT31 (TCR2,α/β-specific). From day 35 through day 74 in culture, the surface phenotype of this clone evolved into CD3+, CD4+, CD8-, TCR2+, TCR1-, and was further characterized as CD2+, CD45RO+, CD16-, and CD56-. The presence of mRNA for TCRαandγbut not ,andγchains was confirmed by Northern blotting. Accessory cell-dependent autocrine proliferative responses to PHA (most likely driven by IL-2) were initially absent, but became measurable at the same time as the TCR was acquired. However, in the absence of PHA, the clone failed to respond to a panel of homozygous B-cell lines representing the majority of MHC class II alleles. Autoreactivity was also not demonstrable. Cytotoxicity was limited to MHC unrestricted “natural killer (NK)-like” lysis of K562 target cells, with no autocytotoxicity detected. Tle NK-like lysis diminished over time in parallel with the acquisition of surface TCR. The cloned cells were not suppressive for mature lymphocyte proliferation. After stimulation, the cells secreted tumor necrosis factorαand granulocyte/macrophage colony-stimulating factor (GM-CSF) detected by immunoassays, and T-cell growth factors, most likely IL-2, as detected by bioassays. Polymerase chain-reaction methods demonstrated the presence of mRNA for IL-2, IL-3, IL-4, IL-9, interferon-δ, and GM-CSF in these cells after stimulation with PHA and B-LCL.These results suggest that cells with the phenotype and some functional characteristics of mature T lymphocytes can evolve extrathymicallyin vitrofrom T-cell precursors sorted from normal human bone marrow.

RATIONALE FOR THE SELECTION OF RICIN A-CHAIN ANTI-T IMMUNOTOXINS FOR MATURE T CELL DEPLETION

1987 ◽  
Vol 44 (6) ◽  
pp. 763-769 ◽  
Author(s):  
JEAN-MARIE DEROCQ ◽  
GUY LAURENT ◽  
PIERRE CASELLAS ◽  
HUBERT VIDAL ◽  
P. PONCELET ◽  
...  
Keyword(s):  
T Cell ◽  
Cell Depletion ◽  
Ricin A Chain ◽  
T Cell Depletion ◽  
A Chain ◽  
Ricin A ◽  
Selection Of

scholarly journals Characterization of a new T-lineage glycoprotein expressed in mature T- cell leukemias and lymphomas

Blood ◽  
1990 ◽  
Vol 75 (7) ◽  
pp. 1557-1563
Author(s):  
WF Cassano
Keyword(s):  
T Cell ◽  
Surface Membrane ◽  
Lymphocytic Leukemia ◽  
Amino Acid Sequence Analysis ◽  
Normal Human ◽  
T Cell Malignancies ◽  
Murine Monoclonal Antibodies ◽  
Immunoglobulin Supergene Family ◽  
Supergene Family

Abstract We identified a new human, T-lineage restricted glycoprotein of molecular weight 120 Kd that is expressed primarily in mature T-cell malignancies. The antigen, named TCA-1 (T-cell cytoplasmic antigen), is an intracellular glycoprotein found mainly in the Golgi stacks, although a few cell lines also display surface membrane TCA-1. Many but not all T-cell neoplasms express this antigen. The antigen is absent from neoplastic and normal human tissue outside the T-lymphocyte lineage. TCA-1 was identified by murine monoclonal antibodies produced after immunization of mice with T-cell chronic lymphocytic leukemia cells. The glycoprotein is a monomer containing approximately 4% N- linked carbohydrate with terminal D-galactose residues. Partial amino acid sequence analysis of TCA-1 shows homology with an immunoglobulin heavy chain region, which suggests that TCA-1 may belong to the immunoglobulin supergene family of receptor and adhesion molecules.

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