C C Chou

University of Alabama, Tuscaloosa, AL, USA

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Publications (18)76.55 Total impact

  • Article: SCH-C (SCH 351125), an orally bioavailable, small molecule antagonist of the chemokine receptor CCR5, is a potent inhibitor of HIV-1 infection in vitro and in vivo.
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    ABSTRACT: We describe here the identification and properties of SCH-C (SCH 351125), a small molecule inhibitor of HIV-1 entry via the CCR5 coreceptor. SCH-C, an oxime-piperidine compound, is a specific CCR5 antagonist as determined in multiple receptor binding and signal transduction assays. This compound specifically inhibits HIV-1 infection mediated by CCR5 in U-87 astroglioma cells but has no effect on infection of CXCR4-expressing cells. SCH-C has broad and potent antiviral activity in vitro against primary HIV-1 isolates that use CCR5 as their entry coreceptor, with mean 50% inhibitory concentrations ranging between 0.4 and 9 nM. Moreover, SCH-C strongly inhibits the replication of an R5-using HIV-1 isolate in SCID-hu Thy/Liv mice. SCH-C has a favorable pharmacokinetic profile in rodents and primates with an oral bioavailability of 50-60% and a serum half-life of 5-6 h. On the basis of its novel mechanism of action, potent antiviral activity, and in vivo pharmacokinetic profile, SCH-C is a promising new candidate for therapeutic intervention of HIV infection.
    Proceedings of the National Academy of Sciences 11/2001; 98(22):12718-23. · 9.68 Impact Factor
  • Article: Human B cell-attracting chemokine 1 (BCA-1; CXCL13) is an agonist for the human CXCR3 receptor.
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    ABSTRACT: The CXC chemokine CXCL13, known as BCA-1 (B cell-attracting chemokine 1) or BLC (B-lymphocyte chemoattractant), has been identified as an efficacious attractant selective for B lymphocytes. The chemokine receptor BLR1 (Burkitt's lymphoma receptor 1)/CXCR5 expressed by all mature B cells has to date been identified as the only known receptor for BCA-1. As the loss of the BLR1/CXCR5 receptor is sufficient to disrupt organization of follicles in spleen and Peyer's patches, BCA-1 may act as a B cell homing chemokine. Nonetheless, BCA-1 has not been tested against all known chemokine receptors. In this study, we report that human BCA-1 competes with radiolabeled interferon gamma (IFN-gamma) inducible protein 10 (IP-10) for binding to the human CXCR3 receptor expressed in Ba/F3 and 293EBNA cell lines. Furthermore, human BCA-1 is an efficacious attractant for human CXCR3 transfected cells; BCA-1-induced chemotaxis is inhibited by a monoclonal antibody against human CXCR3. In these cells, as in human B lymphocytes expressing CXCR5, BCA-1 does not induce a calcium flux. Indeed, BCA-1 attenuates the calcium flux induced by IP-10. In addition, human BCA-1 is an agonist in stimulating GTP gamma S binding. Together these data suggest that human BCA-1 is a specific and functional G-protein-linked chemotactic ligand for the human CXCR3 receptor. The biological significance of this new finding is supported by our recent observation that human BCA-1 induces chemotaxis of activated T cells and the BCA-1-induced chemotaxis is inhibited by a monoclonal antibody against human CXCR3.
    Cytokine 09/2001; 15(3):113-21. · 3.02 Impact Factor
  • Article: Mapping and characterization of the epitope(s) of Sch 55700, a humanized mAb, that inhibits human IL-5.
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    ABSTRACT: mAb against human IL-5 inhibit pulmonary eosinophilia, tissue damage and airway hyper-reactivity in allergic animal models. Sch 55700 is a humanized, neutralizing anti-IL-5 antibody. To better understand the molecular mechanism by which Sch 55700 blocks IL-5 bioactivity, we have mapped its epitope by scanning IL-5 with synthetic peptides. Those peptides containing a region, ERRRV, corresponding to amino acids 89-93 of IL-5 specifically interact with both Sch 55700 and its parental rat IgG, 39D10. Among the five residues of this region, all three arginine residues were particularly critical for interaction of these peptides with Sch 55700. We further characterized this region by alanine scanning using site-directed mutagenesis. Examination of COS-expressed IL-5 mutants by Western blot showed that single mutations of E(89), R(90), R(91) or R(92) to alanine caused a loss of IL-5 binding to both Sch 55700 and 39D10. We further demonstrated in surface plasmon resonance studies using a BIAcore biosenosor that E(89), R(90) or R(91) are involved in the interaction between IL-5 and its receptor alpha subunit. Based upon the findings here and previously reported structures of the IL-5 and 39D10 variable region, we propose a model suggesting that the molecular interactions between the IL-5 and Sch 55700 mainly involve several ion pair interactions. We conclude that Sch 55700 occupies a region, ERRR, on IL-5 that is essential for its interaction with the receptor and thereby blocks IL-5 bioactivity.
    International Immunology 01/2000; 11(12):1935-44. · 3.41 Impact Factor
  • Article: Effect of Sch 55700, a humanized monoclonal antibody to human interleukin-5, on eosinophilic responses and bronchial hyperreactivity.
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    ABSTRACT: This report describes the development and the biology of Sch 55700, a humanized monoclonal antibody to human IL-5 (hIL-5). Sch 55700 was synthesized using CDR (complementarity determining regions) grafting technology by incorporating the antigen recognition sites for hIL-5 onto consensus regions of a human IgG4 framework. In vitro, Sch 55700 displays high affinity (Kd = 20 pmol/l) binding to hIL-5, inhibits the binding of hIL-5 to Ba/F3 cells (IC50 = 0.5 nmol/l) and blocks IL-5 mediated proliferation of human erythroleukemic TF-1 cells. In allergic mice, Sch 55700 (0.1-10 mg/kg, i.p. or i.m.) inhibits the influx of eosinophils in the lungs, demonstrates long duration of activity and the anti-inflammatory activity of this compound is additive with oral prednisolone. In allergic guinea pigs, Sch 55700 (0.03-30 mg/kg i.p.) inhibits both the pulmonary eosinophilia and airway hyperresponsiveness and at 30 mg/kg, i.p. inhibited allergic, but not histamine-induced bronchoconstriction. In allergic rabbits, Sch 55700 blocks cutaneous eosinophilia. Sch 55700 (0.1-1 mg/kg i.p.) also blocks the pulmonary eosinophilia and neutrophilia caused by tracheal injection of hIL-5 in guinea pigs. In allergic cynomolgus monkeys, a single dose of Sch 55700 (0.3 mg/kg i.v.) blocks the pulmonary eosinophilia caused by antigen challenge for up to six months. Sch 55700 is, therefore, a potent antibody against IL-5 in vitro and in a variety of species in vivo that could be used to establish the role of IL-5 in human eosinophilic diseases such as asthma.
    Arzneimittel-Forschung 10/1999; 49(9):779-90. · 0.72 Impact Factor
  • Article: Cutting edge: species specificity of the CC chemokine 6Ckine signaling through the CXC chemokine receptor CXCR3: human 6Ckine is not a ligand for the human or mouse CXCR3 receptors.
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    ABSTRACT: The CC chemokine known as 6Ckine (SLC, Exodus-2, or TCA4) has been identified as a ligand for CCR7. Mouse 6Ckine has also been shown to signal through mouse CXCR3 and share some of the activities of IFN-gamma inducible protein 10 and monokine induced by IFN-gamma. Nonetheless, human 6Ckine has not been shown to bind CXCR3 receptor or have angiostatic activity. In this study, we report that human 6Ckine does not induce a calcium flux in either human CXCR3 or mouse CXCR3 transfected cells, although it is an equally potent agonist as mouse 6Ckine and human macrophage inflammatory protein-3beta in human CCR7 transfected cells. Mouse 6Ckine (but not human 6Ckine) is capable of competing with radiolabeled IFN-gamma inducible protein 10 for human CXCR3. In addition, radiolabeled human 6Ckine does not bind to either human CXCR3 or mouse CXCR3. Together these data suggest that human CC chemokine 6Ckine is not a ligand for the human or mouse CXC chemokine receptor CXCR3.
    The Journal of Immunology 05/1999; 162(7):3765-9. · 5.79 Impact Factor
  • Article: An inhibitor of CD28-CD80 interactions impairs CD28-mediated costimulation of human CD4 T cells.
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    ABSTRACT: We have identified and characterized a microbial extract-derived inhibitor of T cell CD28-dependent costimulation, NP1835-2, utilizing an in vitro system in which anti-human CD3 antibody and a human CD80-Ig fusion protein are immobilized on protein A-coated microspheres. This system is CD28-CD80-dependent, as judged by the specific ability of anti-CD80 antibody or cytotoxic T lymphocyte antigen-4-Ig to block human CD4 T cell responses. Activation of CD4 T cells in this system in presence of NP1835-2 resulted in a concentration-dependent inhibition of T cell proliferation (IC50 of 1-4 microg/ml), surface activation marker expression, and the production of many T cell cytokines, with the exception of TGFbeta. Impairment of T cell activation correlated with a blockade of cell cycle progression at G0/G1 and was only partly restored by addition of 100 U/ml IL-2. No inhibition by NP1835-2 of T cell proliferation stimulated by plate-bound anti-CD3 antibody, phorbol 12-myristate 13-acetate + A23187, or P815 cells expressing the costimulatory molecule CD58 was observed. NP1835-2 was unable to modulate anti-IgM-stimulated B cell proliferation or LPS-induced monocyte activation. Suboptimal concentrations of NP1835-2 and cyclosporin together were able to impair T cell activation in an additive fashion. NP1835-2 was also able to inhibit the primary human MLR. These data indicate that NP1835-2 may belong to a class of molecules capable of selectively impairing CD28-mediated T cell costimulation and suggest its potential usefulness in the treatment of a variety of T cell-dependent diseases. Moreover, NP1835-2 may serve as a useful probe for investigating the mechanisms involved in T cell nonresponsiveness.
    Cellular Immunology 02/1999; 191(1):49-59. · 1.97 Impact Factor
  • Article: Expression, purification, and characterization of recombinant human interleukin-13 from NS-O cells.
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    ABSTRACT: Interleukin-13 is a cytokine which is secreted by activated T lymphocytes and primarily impacts monocytes, macrophages, and B cells. A synthetic gene coding for human interleukin-13 has been prepared and cloned into expression vector pEE12. The construct was transfected into NS-O cells, which showed stable expression of the recombinant protein. A four-step purification procedure consisting of S-Sepharose, Q-Sepharose, hydroxyapatite, and Sephacryl-100 chromatographies yielded bioactive interleukin-13 of > 98% purity. The purified protein was structurally characterized. The extinction coefficient at 280 nm was determined to be 5678 M-1 cm-1. Amino acid sequencing confirmed that the N-terminus of the purified protein was intact. Electrospray mass spectrometric analysis, size-exclusion chromatography, and SDS-PAGE revealed that the biologically active protein is monomeric and unglycosylated. Mass spectrometry and a chemical assay for free sulfhydryls indicated that the four cysteine residues of interleukin-13 are involved in two intramolecular disulfide bonds. The circular dichroism spectrum confirms that interleukin-13 belongs to the alpha-helical family of cytokines. A biologically inactive covalent trimer also forms in the cell culture, but can be separated from the monomer by the hydroxyapatite and size-exclusion chromatographies. These data indicate that human interleukin-13 retains many structural similarities to human interleukin-4, from which it arose by a gene duplication event.
    Protein Expression and Purification 04/1998; 12(2):239-48. · 1.59 Impact Factor
  • Article: Development of a CD28 receptor binding-based screen and identification of a biologically active inhibitor.
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    ABSTRACT: CD28 is a T-cell costimulatory receptor which plays a pivotal role in antigen-induced T-cell response. We have developed a cell-free and scintillation-proximity assay-based screen to search for molecules that inhibit ligand binding to CD28. The assay was shown to be versatile and adaptable to automation for high-throughput screening. Using this assay, we identified an inhibitor of CD28, NP2214. The inhibitor was shown to be active in vitro by suppressing IL-2 synthesis and proliferation of peripheral blood mononuclear cells in response to CD28 costimulation. We also demonstrated the additive effects of NP2214 and cyclosporine A which act mechanistically distinctly in inhibiting costimulation-induced IL-2 synthesis.
    Analytical Biochemistry 03/1998; 256(1):47-55. · 3.00 Impact Factor
  • Article: Characterization of potential antagonists of human interleukin 5 demonstrates their cross-reactivity with receptors for interleukin 3 and granulocyte-macrophage colony-stimulating factor.
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    ABSTRACT: The ligand-binding alpha-chain of the human interleukin 5 (IL-5) receptor was expressed in its soluble form, lacking the transmembrane and cytoplasmic domains, from recombinant baculovirus. The soluble receptor was used in a scintillation proximity assay to identify two chemical compounds that inhibit binding of human IL-5 to the soluble receptor alpha chain with IC50 of 8 microM and 11 microM. These compounds also inhibited the interaction of human IL-5 with its membrane-bound receptor, composed of the ligand-binding alpha chain and signal-transducing beta chain, and prevented signaling through the receptor. Analysis by surface plasmon resonance and matrix-assisted laser-desorption/ionization mass spectrometry showed that the identified compounds bound irreversibly to the receptor at a 1:1 (mol/mol) ratio, suggesting a covalent interaction with the alpha chain of the human IL-5 receptor. Both compounds also inhibited the interaction of the receptors for interleukin 3 (IL-3) and granulocyte-macrophage colony-stimulating factor (GM-CSF), which are involved in hematopoietic differentiation and activation of immune cells, thus eliminating them as potential therapeutic agents. The inhibition of the structurally closely related receptors for IL-5, IL-3 and GM-CSF by both compounds, while binding of interleukin-4 to its receptor was not affected, suggests that a similar reactive site exists in the ligand-binding domains of the receptors for IL-5, IL-3 and GM-CSF.
    European Journal of Biochemistry 07/1997; 246(3):625-32. · 3.58 Impact Factor
  • Article: Characterization of interleukin-10 receptor expression on B-cell chronic lymphocytic leukemia cells.
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    ABSTRACT: B-cell chronic lymphocytic leukemia (B-CLL) cells accumulate in vivo in the G0/G1 phase of the cell cycle, suggesting that their malignant expansion is due, at least in part, to a delay in cell death. However, the cellular or molecular factors responsible for a delay in B-CLL cell death are unknown. B-CLL cells do express receptors for interferon-alpha (IFN-alpha) and IFN-gamma, and activation of both has been shown to promote B-CLL survival in vitro by preventing apoptosis. The interleukin-10 (IL-10) receptor is another member of the IFN receptor family, but its ligand, IL-10, has been reported to induce apoptosis in B-CLL cells. In the current study, we undertook a biochemical analysis of IL-10 receptor expression on freshly isolated B-CLL cells and characterized the functional responsiveness of IL-10 binding to its constitutively expressed receptor. We show that B-CLL cells bind IL-10 with significant specificity and express between 47 and 127 IL-10 receptor sites per cell, with a dissociation constant in the range of 168 to 426 x 10(-12) mol/L. Ligand binding and activation of the IL-10 receptor expressed on B-CLL cells results in the phosphorylation of signal transducer and activator of transcription 1 (STAT1) and STAT3 proteins. This pattern of STAT protein phosphorylation is identical to IL-10 receptor activation on normal cells and similar to IFN-alpha (STAT1 and STAT3) and IFN-gamma (STAT1) receptor activation in CLL. Further, in consecutive samples of fresh blood obtained from patients with B-CLL cells, the addition of IL-10 inhibited B-CLL proliferation, enhanced B-CLL differentiation, but did not induce apoptosis. Indeed, IL-10, like IFN-gamma, was able to significantly reduce the amount of B-CLL cell death caused by hydrocortisone-induced apoptosis. We conclude that cytokines, which signal through the interferon family of receptors, have comparable functional effects on B-CLL cells.
    Blood 07/1997; 89(11):4146-52. · 9.90 Impact Factor
  • Article: Pulmonary biology of anti-interleukin 5 antibodies.
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    ABSTRACT: Interleukin-5 (IL-5) is a critical cytokine for the maturation of eosinophil precursors to eosinophils in the bone marrow and those eosinophils then accumulated in the lungs during asthma. We have studied anti IL-5 antibodies on allergic responses in mice, guinea pigs and monkeys and are extending this experiment into humans with a humanized antibody. In a monkey model of pulmonary inflammation and airway hyperreactivity, we found that the TRFK-5 antibody blocked both responses for three months following a single does of 0.3 mg/kg, i.v. This antibody also blocked lung eosinophilia in mice by inhibiting release from the bone marrow. To facilitate multiple dosing and to reduce immunogenicity in humans, we prepared Sch 55700, a humanized antibody against IL-5. Sch 55700 was also active against lung eosinophilia in allergic monkeys and mice and against pulmonary eosinophilia and airway hyperresponsiveness in guinea pigs. Furthermore, as opposed to steroids, Sch 55700 did not cause immunosuppression in guinea pigs. Studies with this antibody in humans will be critical to establishing the therapeutic potential of IL-5 inhibition.
    Memórias do Instituto Oswaldo Cruz 02/1997; 92 Suppl 2:69-73. · 2.15 Impact Factor
  • Article: Pulmonary biology of anti-interleukin 5 antibodies
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    ABSTRACT: Interleukin 5 (IL-5) is a critical cytokine for the maturation of eosinophil precursors to eosinophils in the bone marrow and those eosinophils then accumulate in the lungs during asthma. We have studied anti IL-5 antibodies on allergic responses in mice, guinea pigs and monkeys and are extending this experiment into humans with a humanized antibody. In a monkey model of pulmonary inflammation and airway hyperreactivity, we found that the TRFK-5 antibody blocked both responses for three months following a single dose of 0.3 mg/kg, i.v. This antibody also blocked lung eosinophilia in mice by inhibiting release from the bone marrow. To facilitate multiple dosing and to reduce immunogenicity in humans, we prepared Sch 55700, a humanized antibody against IL-5. Sch 55700 was also active against lung eosinophilia in allergic monkeys and mice and against pulmonary eosinophilia and airway hyperresponsiveness in guinea pigs. Furthermore, as opposed to steroids, Sch 55700 did not cause immunosuppression in guinea pigs. Studies with this antibody in humans will be critical to establishing the therapeutic potential of IL-5 inhibition.
    Memórias do Instituto Oswaldo Cruz. 01/1997;
  • Article: Structure and humanization of a rat monoclonal Fab to human interleukin-5.
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    ABSTRACT: The X-ray crystal structure of a rat monoclonal Fab JES1-39D10, raised against recombinant human interleukin-5, has been determined with the use of molecular replacement techniques and refined at 2.7 A resolution by simulated annealing. The overall structure is similar to a murine Fab HyHEL-10 that is specific for hen egg white lysozyme. An interesting feature of the structure is the presence of leucine residues to support the H1 complementarity-determining region (CDR) loop. To our knowledge this is the first Fab crystal structure containing this unusual H1 loop support pattern. The activity of three humanized versions of 39D10 is explained by analysis of Fv interface residues and H1 support patterns of 39D10 and the human template HIL.
    Protein engineering 08/1996; 9(7):623-8.
  • Article: The functional characterization of interleukin-10 receptor expression on human natural killer cells.
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    ABSTRACT: Human natural killer (NK) cells are large granular lymphocytes that constitutively express functional forms of the interleukin-2 receptor (IL-2R) and lyse tumor and virally infected cells without prior sensitization. NK cells with high density expression of CD56 (CD56bright) express the high affinity IL-2R and proliferate in response to low (picomolar) concentrations of IL-2. CD56dim NK cells express the intermediate affinity IL-2R and demonstrate enhanced cytotoxic activity without proliferation in response to high (nanomolar) concentrations of IL-2. In the present study, we characterized IL-10R expression on human NK cells and the functional consequences of IL-10 binding directly to highly purified subsets of CD56bright and CD56dim NK cells. Binding studies using 125I-IL-10 indicated that resting human NK cells constitutively express the IL-10 receptor protein at a surface density of approximately 90 receptor sites per cell, with a kd of approximately 1 nmol/L. Alone, IL-10 did not induce proliferation of CD56bright or CD56dim NK cell subsets. However, at low concentrations (0.5 to 5 ng/mL), IL-10 significantly augmented IL-2-induced proliferation of the CD56bright NK cell subset mediated via the high-affinity IL-2R. In the absence of IL-2, IL-10 was able to induce significant NK cytotoxic activity against NK-resistant tumor cell targets in both subsets of NK cells in a dose-dependent fashion. Furthermore, the combination of IL-10 and IL-2 had an additive effect on NK cytotoxic activity, whereas that of IL-10 and IL-12 did not. Production of interferon-gamma, tumor necrosis factor-alpha, and granulocyte-macrophage colony-stimulating factor by IL-2-activated NK cells was also significantly enhanced by IL-10. Neither resting nor activated human NK cells appear to produce human IL-10 protein. In summary, NK cells constitutively express the IL-10R protein in low density, and the functional consequences of IL-10 binding directly to human NK cell subsets appear to be stimulatory and dose-dependent. In contrast to its direct effects on human T cells and monocytes/macrophages, IL-10 potentiates cytokine production by human NK cells.
    Blood 07/1995; 85(12):3577-85. · 9.90 Impact Factor
  • Article: Characterization of recombinant extracellular domain of human interleukin-10 receptor.
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    ABSTRACT: The extracellular region of the human interleukin-10 (hIL-10) receptor was expressed using a myeloma cell line and was purified to homogeneity by ligand-affinity chromatography. SDS-polyacrylamide gel electrophoresis analysis indicated that the soluble receptor is glycosylated and has an apparent molecular mass of 35,000-45,000. Under native conditions, soluble hIL-10 receptor was determined by gel filtration to be a monomeric protein. Soluble hIL-10 receptor was able to inhibit the binding of 125I-hIL-10 to the full-length receptor and was able to antagonize the effect of human IL-10 in cell proliferation and cytokine synthesis inhibition. The apparent dissociation constant (Kd) of soluble hIL-10 receptor was determined to be 563 +/- 59 pM, approximately 2- to 10-fold higher than that found on intact cells (Tan, J. C., Indelicato, S. R., Narula, S. K., Zavodny, P. J., and Chou, C.-C. (1993) J. Biol. Chem. 268, 21053-21059; Liu, Y., Wei, S. H.-Y., Ho, A. S.-Y., de Waal Malefyt, R., and Moore, K. W. (1994) J. Immunol. 152, 1821-1829). When hIL-10 binds soluble hIL-10 receptor in solution, a single complex was detected by gel filtration, and the complex was found to consist of two hIL-10 dimers and four soluble receptor monomers, suggesting that hIL-10 may induce a novel mode of oligomerization of the receptor upon binding.
    Journal of Biological Chemistry 06/1995; 270(21):12906-11. · 4.77 Impact Factor
  • Article: Lymphomagenesis in the SCID-hu mouse involves abundant production of human interleukin-10.
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    ABSTRACT: Both human (hu) and viral (v) interleukin-10 (IL-10) appear to be important cofactors in the survival and growth of lymphoblastoid cell lines infected with Epstein-Barr virus (EBV). When mice with severe combined immune deficiency (SCID) are injected with human peripheral blood lymphocytes (PBL) from normal individuals who are seropositive for EBV, the majority of hu-PBL-SCID mice will develop an EBV-associated lymphoproliferative disease (EBV-LPD) of human B-cell origin, not unlike some cases of EBV-LPD that are seen in immunocompromised individuals. The role of huIL-10 or vIL-10 in this chimeric mouse model of EBV-LPD is unknown. In the present study, we show that hu-PBL-SCID mice that develop EBV-LPD have significant elevation of serum huIL-10 levels compared with mice that do not develop EBV-LPD (P = .005). vIL-10 was undetectable in all animals. The EBV+ tumor samples express transcript for huIL-10 and huIL-10 receptor, express huIL-10 protein by immunohistochemical staining, and show specific binding of recombinant (r) huIL-10. In vitro analysis of the functional consequences of rhuIL-10 binding to IL-10 receptors on fresh EBV+ tumor cells shows that rhuIL-10 can prevent programmed cell death as well as promote proliferation and can do so at concentrations of huIL-10 found in vivo. Thus, huIL-10 production by EBV+ tumor cells may contribute directly to their malignant outgrowth in the hu-PBL-SCID mouse by two autocrine mechanisms: prevention of programmed cell death and proliferation. The implications of such findings with regard to EBV-LPD in humans is discussed.
    Blood 03/1995; 85(4):1063-74. · 9.90 Impact Factor
  • Source
    Article: Characterization of interleukin-10 receptors on human and mouse cells.
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    ABSTRACT: Human interleukin (IL)-10 is a pleiotropic cytokine acting on a variety of immune cells. Here we show that the protein can be enzymatically iodinated to high specific radioactivity with retention of biological activity. The radiolabeled ligand binds specifically to its receptor in several mouse and human cell lines, notably human B-lymphoma line JY and mouse mast cell line MC/9. Human IL-10 apparently binds as a dimer to a single class of receptor in both the JY and MC/9 cell lines with a Kd in the 50-200 pM range. Interestingly, mouse IL-10 was capable of blocking binding of human IL-10 to mouse but not human cells. There appears to be at most only a few hundred IL-10 receptors/cell for both mouse and human cell lines examined. Chemical cross-linking of the radioiodinated hIL-10 to JY and MC/9 cells revealed a common protein complex with an apparent molecular mass of about 97 kDa. Additional high molecular weight complexes were detected with JY but not MC/9 cells.
    Journal of Biological Chemistry 11/1993; 268(28):21053-9. · 4.77 Impact Factor
  • Article: Inhibition of pulmonary eosinophilia and hyperreactivity by antibodies to interleukin-5.
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    ABSTRACT: Eosinophils infiltrate into the lungs during asthma and may cause the damage associated with pulmonary inflammation. In allergic animal models, antibodies to interleukin (IL)-5 inhibit pulmonary eosinophilia, tissue damage and hyperreactivity. Sch 55700, a humanized antibody against human IL-5, inhibits eosinophilia in these models with an extended biological duration. On the basis of this dosing regimen and the humanized nature of Sch 55700, it is anticipated that the host response leading to tolerance would be minimized.
    International Archives of Allergy and Immunology 08/1970; 107(1-3):321-2. · 2.40 Impact Factor