Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0023418 (leukemia)
 93,477 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Adult T cell leukemia-derived factor (ADF)/Thioredoxin (TRX), originally defined as an IL-2 receptor alpha-chain/p55 inducer, has many cytokine-like activities. We reported that the release of major basic protein (MBP) from mature eosinophils stimulated with cytochalasin B and C5a were augmented after preincubation with recombinant ADF/TRX. The addition of a TRX specific inhibitor, BE40644, suppressed the augmentation of MBP release from mature eosinophils. It is suggested that BE40644 is applicable in allergic diseases associated with eosinophils.
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PMID:Role of ADF/TRX and its inhibitor on the release of major basic protein from human eosinophils. 765 31

Abnormal trafficking of chronic lymphocytic leukemia (CLL) cells may account for the differences in accumulation of malignant lymphocytes within the bone marrow and lymphoid tissues of this lymphoproliferative disorder. We therefore hypothesized that CLL cells aberrantly express one or more receptors involved in lymphocyte trafficking. Leukemia cells from patients with B-cell CLL showed no quantitative difference in surface expression of L-selectin, LFA-1, or CD44 by flow cytometry compared to normal B cells. Analysis of L-selectin by dodecyl sulfate/polyacrylamide gel electrophoresis (SDS-PAGE) and Western blot, however, demonstrated a consistent, reproducible approximately 3.7 kDa decrease in the M(r) of L-selectin on CLL cells compared to normal B cells. In contrast, Western blot analysis revealed no obvious qualitative abnormality in either CD11a (the alpha-chain of LFA-1) or CD44 on CLL cells. Analysis of L-selectin cDNA by polymerase chain reaction revealed identically sized products for both normal and CLL cells, suggesting that the abnormality in M(r) does not result from a difference in primary structure. Inhibition of N-linked glycosylation by tunicamycin resulted in the production of identical-sized nascent L-selectin by normal and CLL cells. These studies demonstrate that L-selectin on CLL cells is aberrantly glycosylated compared to normal peripheral blood lymphocytes. The functional importance of this aberrant glycosylation is unclear, however, since L-selectin is shed normally from phorbol myristate acetate (PMA)-stimulated CLL cells and since normal and CLL lymphocytes bind equally well in vitro to high endothelial venules. Understanding the mechanism that accounts for the aberrance may provide important insights into the molecular basis of CLL.
Leukemia 1993 Sep
PMID:Aberrant glycosylation of L-selectin on the lymphocytes of chronic lymphocytic leukemia. 769 Apr 38

Cord blood has been used successfully for stem cell transplantation in several haematological conditions: Fanconi's anaemia, leukaemia and Wiskott-Aldrich syndrome. On account of the low incidence of GVHD observed following cord blood transplantation, it has been suggested that cord blood be used for HLA-matched, or perhaps one or two antigens mismatched, and unrelated stem cell transplantation. Based on an extensive immunophenotype-functional correlation, we determined that cord blood contains mainly immature unprimed T lymphocytes that are predominantly suppressor cells. Recent findings suggest that dysregulated production of cytokines (IL-1, IL-2, TNF alpha) plays a role in GVHD. We showed that T cells in cord blood express receptors for IL-2, TNF alpha, but no receptors for IL-1. Similarly, NK cells, one of the effector cells of GVHD, express receptors for TNF alpha and gamma IFN but do not express receptors for IL-1, nor IL-2R alpha-chain (CD25) although IL-2R beta-chain is expressed. The potential for activation of T lymphocytes and NK cells therefore exists in the context of bone marrow transplantation. However, the high number of suppressor cells in cord blood most likely modulate the activation of lymphocytes and NK cells thereby minimizing GVHD.
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PMID:Phenotypic analysis of functional T-lymphocyte subtypes and natural killer cells in human cord blood: relevance to umbilical cord blood transplantation. 777 9

An adult mouse liver cDNA library was screened with oligonucleotides corresponding to the conserved WSXWS motif of the haemopoietin receptor family. Using this method, cDNA clones encoding a novel receptor were isolated. The new receptor, named NR1, was most similar in sequence and predicted structure to the alpha-chain of the IL-6 receptor and mRNA was expressed in the 3T3-L1 pre-adipocytic cell line and in a range of primary tissues. Expression of NR1 in the factor-dependent haemopoietic cell line Ba/F3 resulted in the generation of low affinity receptors for IL-11 (Kd approximately 10 nM). The capacity to bind IL-11 with high affinity (Kd = 300-800 pM) appeared to require coexpression of both NR1 and gp130, the common subunit of the IL-6, leukaemia inhibitory factor (LIF), oncostatin M (OSM) and ciliary neurotrophic factor (CNTF) receptors. The expression of both NR1 and gp130 was also necessary for Ba/F3 cells to proliferate and M1 cells to undergo macrophage differentiation in response to IL-11.
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PMID:Cloning of a murine IL-11 receptor alpha-chain; requirement for gp130 for high affinity binding and signal transduction. 795 45

Increased serum concentration of soluble alpha-chain receptor for interleukin-2 (sIL-2R) has been noted in patients with a variety of inflammatory conditions and lymphoid malignancies including T cell leukemia and lymphoma. Elevated sIL-2R serum levels seen in lymphoid malignancies appear to correlate with the clinical stage of disease. However, because sIL-2R is produced by normal activated lymphocytes, it has been uncertain whether serum sIL-2R in such conditions is derived from tumor cells or normal immune cells responding to the tumor. To address this question, we used a model of human (CD30+) anaplastic, large T cell lymphoma transplanted into immunodeficient SCID mice. Reverse transcription polymerase chain reaction of tumor RNA showed that the tumor, designated mJB6, contains mRNA for alpha-chain of human IL-2R. Furthermore, 15 to 25% of tumor cells stained with anti-human IL-2R alpha-chain mAb. Solid phase ELISA analysis of serum samples from mice bearing mJB6 lymphoma showed high concentrations of human sIL-2R. None of the control mice without lymphoma or with human nonlymphoid tumors (prostatic carcinoma, ovarian carcinoma, and glioblastoma multiforme) showed detectable human sIL-2R. The sIL-2R serum titers of mJB6-bearing mice correlated strongly with tumor volume (P < 0.0001). Tumors as small as 0.4 to 0.8 mm3 could be detected by this method. The sensitivity of sIL-2R ELISA exceeded at least 150 times the sensitivity of conventional radioisotopic tumor detection. Total resection of mJB6 tumors resulted in complete clearance of sIL-2R from the murine serum within 48 hours with a half-life of 6 hours. Accordingly, partial resection led to a significant decrease in sIL-2R followed by gradual increase with tumor regrowth. sIL-2R was also detected in the urine of mJB6-transplanted mice. As in serum, urine concentrations of sIL-2R were proportional to tumor mass (P < 0.02). Based on these findings we postulate that malignant cells are a major source of serum sIL-2R in patients with lymphoid tumors. In addition, our data further support monitoring sIL-2R concentration in body fluids as a sensitive method to detect change in tumor volume in such patients.
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PMID:Constitutive secretion of soluble interleukin-2 receptor by human T cell lymphoma xenografted into SCID mice. Correlation of tumor volume with concentration of tumor-derived soluble interleukin-2 receptor in body fluids of the host mice. 817 32

Adult T cell leukemia-derived factor (ADF), originally defined as an IL-2 receptor alpha-chain (IL-2R alpha)/p55 (Tac) inducer, is a human thioredoxin homologue and has many cytokine-like activities. In this study, we examined the regulatory effect of ADF on eosinophil migration using human eosinophils and an eosinophilic subline of HL-60 human promyelocytic leukemia cells, YY-1. rADF induced migration of eosinophils from patients with hypereosinophilia, although rADF exhibited little activity on eosinophils from healthy donors. When human eosinophils were incubated with rADF (0.1-10 micrograms/ml) at 37 degrees C for 24 h, both chemotactic and chemokinetic activity of the complement anaphylatoxin peptide C5a on eosinophil migration was markedly enhanced in a dose-dependent manner. Similarly, this enhancing effect of rADF was observed in the migration assay using YY-1 cells. In contrast, rADF showed no modulation of migratory behavior of human eosinophils and YY-1 cells by IL-3, IL-5, nor granulocyte-macrophage colony-stimulating factor. Scatchard analysis of C5a receptors on YY-1 cells using 125I-C5a showed that rADF modulated neither the density nor the affinity of the cell membrane significantly. Furthermore, mutant ADF (mADF), which had no reducing activity, had no enhancing effect on C5a-induced eosinophil migration. These results indicate a possible involvement of ADF in the recruitment of eosinophils through redox regulation by a dithiol reductase activity.
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PMID:Regulation of eosinophil migration by adult T cell leukemia-derived factor. 822 51

A feline large granular lymphocyte (LGL) cell line was established from a cat with an alimentary-form lymphoma. This cell line, designated as FGL, had many large azurophilic granules in the cytoplasm, which were typical to LGL cells. Proviral genome of feline leukemia virus was detected in the chromosomal DNA of FGL cells, and reverse transcriptase activity was also demonstrated in the culture supernatant. Furthermore, we found expression of interleukin 2 (IL-2) receptor alpha-chain on the cell surface of FGL and its natural killer activity against human erythroblastic leukemia cell line, K562.
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PMID:Establishment and characterization of a feline large granular lymphoma cell line expressing interleukin 2 receptor alpha-chain. 828 47

The X region of human T-cell leukemia virus type I (HTLV-I) encodes two proteins that regulate viral gene expression. The tax protein is the product of the transactivator gene and has been shown to up-regulate the expression of some cellular genes controlling T-cell replication, including that of the interleukin-2 (IL-2) T-cell growth hormone and the alpha chain of its receptor (IL-2R). Several studies have shown that tax transactivation of the IL-2R alpha-chain promoter is mediated by binding sites for the transcriptional activator NF-kappa B, and this mechanism has also been implicated in the tax activation of IL-2 promoter activity. The rex gene product of HTLV-I regulates viral protein production by influencing mRNA expression and has been implicated in the stabilization of IL-2R alpha-chain mRNA. In the present studies, the ability of the tax and rex proteins to transactivate IL-2 gene expression has been reinvestigated. The ability of the tax protein to transactivate IL-2 promoter activity appears, at least in part, to be mediated by the recognition sequence for a DNA-binding complex known as CD28RC. Consistent with this hypothesis is the observation that tax-mediated activation of IL-2 gene expression is resistant to the immunosuppressive affects of cyclosporin A, a property postulated for the CD28RC binding complex. Unexpectedly, this tax-mediated up-regulation of IL-2 expression is synergized by the presence of the rex protein. These findings demonstrate that transactivation of IL-2 gene expression by tax is augmented by mechanisms distinct from NF-kappa B and raise the possibility that rex, as well as tax, contributes to the oncogenic capability of HTLV-I by altering the expression of the IL-2 gene in T cells infected with this retrovirus.
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PMID:Influence of human T-cell leukemia virus type I tax and rex on interleukin-2 gene expression. 838 12

To date, it is still unclear how the trafficking and retention of activated lymphocytes in periodontal lesions are regulated. In this study, we investigated the molecular basis for the adhesive interactions between lymphocytes and human gingival fibroblasts (HGF). Peripheral blood T lymphocytes (PBT) exhibited binding ability, but only when the calls were activated with phorbol 12-myristate 13-acetate (PMA). Among several human cell lines tested, PMA-stimulated Molt-4, a human T-cell leukaemia line, also displayed significant binding ability to HGF. In order to clarify the molecule(s) involved in this cell-cell interaction, a panel of monoclonal antibodies (mAb) was prepared to PMA-activated Molt-4 and one clone, 4-145, was selected on the basis of its ability to block the binding of PMA-activated Molt-4 to HGF. Moreover, 4-145 inhibited the binding of not only activated Molt-4 but also activated PBT and other cell types to HGF. Biochemical and flow cytometric analyses revealed that 4-145 probably recognizes the beta 1 chain of very late antigen (VLA) integrins. Blocking experiments using mAb specific for the alpha-chain of VLA integrins demonstrated the involvement of alpha 4 (VLA-4) and, to a lesser extent, alpha 5 (VLA-5) chains in the adhesive interactions between T cells and HGF. Despite the significant involvement of VLA integrins in the adhesive interaction between PBT and HGF, the binding of PBT to human dermal fibroblasts (HDF) was not abrogated by 4-145, suggesting that HGF and HDF differ in their requirement of VLA integrins for adhesion to activated PBT. Furthermore, the fact that vascular cell adhesion molecule-1 (VCAM-1), one of the ligands of VLA-4, was not detected on HGF by flow cytometry and anti-fibronectin (FN) Ab did not block the adhesive interaction to HGF suggests that not-yet-identified ligand(s) for VLA-4 might be present on HGF.
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PMID:Very late antigen integrins are involved in the adhesive interaction of lymphoid cells to human gingival fibroblasts. 840 71

Prolymphocytic leukemia (PLL) is closely related to chronic lymphocytic leukemia (CLL), but present with distinctive clinical/laboratory features and associated with much worse prognosis. In this study, we generated three new IgG1-kappa monoclonal antibodies (MoAbs), termed SN8, SN8a and SN8b, by use of an unconventional approach, ie, by using an isolated B PLL antigen preparation to immunize mice. These MoAbs, particularly SN8, showed a highly selective reactivity to B PLL and B non-Hodgkin's lymphoma (NHL) among various human leukemia-lymphoma specimens tested; eg, SN8 was capable of effectively distinguishing B PLL from B CLL as well as from hairy cell leukemia (HCL) cell specimens. The cell surface antigen defined by the three MoAbs was determined to be a covalently linked heterodimeric glycoprotein complex (gp49/40) consisting of a 49,000 dalton (alpha-chain) and a 40,000-dalton component (beta-chain). Epitope comparison showed that the epitope defined by SN8 (SN8 epitope) is in close proximity to SN8a epitope but in a distant position from SN8b epitope. Western blot analysis showed that both SN8 and SN8a epitopes are on the beta-chain, but SN8b epitope was not detected on either the alpha- or the beta-chain of the reduced antigen in the same analysis. Binding of either SN8 or SN8b to the cell surface gp49/40 did not cause significant downregulation of the antigen expression whereas binding of SN8a to the antigen caused small (approximately 20%) decrease in the antigen expression. Among the various normal peripheral blood cells, only a subpopulation (6.0% to 24.2% among different specimens derived from different donors) of B cells reacted with the SN8 series MoAbs; these MoAbs showed no significant reactivity against T cells, granulocytes, monocytes, erythrocytes, and platelets. Minimal or no significant reactivity (0 to 2.6% among different specimens) was detected against normal bone marrow cells. Ricin A-chain conjugates of the three MoAbs are all strongly effective for specific killing of SN8 antigen-expressing leukemia cells in the absence of any potentiators; furthermore, the addition of 10 mmol/L NH4Cl, a potentiator, enhanced strongly the cytotoxic activities of the SN8, SN8a, and SN8b conjugates. Thus, each of the three MoAbs was effectively internalized after binding to the cell surface antigen.
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PMID:Three new monoclonal antibodies that define a unique antigen associated with prolymphocytic leukemia/non-Hodgkin's lymphoma and are effectively internalized after binding to the cell surface antigen. 841 5


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