Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P05231 (interleukin-6)
 23,907 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Multiple cycles of high-dose chemotherapy can be hematologically supported by repeated administration of peripheral blood progenitors obtained after mobilization using cytokine alone or in combination with chemotherapy. We have explored the quality of such cells and their potential to undergo ex vivo expansion. Twenty-five leukapheresis samples from 19 patients who had received extensive prior chemotherapy for stage IV breast cancer were subjected to CD34+ cell selection using immunoaffinity columns of immunomagnetic bead separation. Cells were cultured in suspension in the presence of c-kit ligand, interleukin-3, interleukin-6, erythropoietin, and granulocyte colony-stimulating factor. Ten experiments were performed using weekly exchange of media and cytokines (Delta assay). Median myeloid and erythroid progenitors expanded 15-fold at 7 days (range, 7 to 43), 40-fold at 14 days (range, 18 to 470), 46-fold at 21 days (range, 0 to 118), and 21-fold at 28 days (range, 0 to 61). In a system using gas-permeable bags without exchange of media or cytokine, median progenitors expanded 13-fold at 7 days (range, 7 to 36), 14-fold at 10 days (range, 4 to 61), 14-fold at 12 days (range, 3 to 46), and 10-fold at 14 days (range, 1 to 35). Progenitor expansion less than 10-fold occurred in 8% of experiments at day 7, in 17% at day 10, in 43% at day 12, and in 50% at day 14. When autologous plasma, autologous plasma processed (removal of cryoprecipitate, centrifugation, then filtration), or human serum were substituted for 20% fetal calf serum, the ratio of progenitor expansion at 7 days relative to 20% fetal calf serum for 10% human serum, 20% human serum, and 1% autologous plasma processed was 1.01 (range, 0.62 to 1.33), 0.88 (range, 0.61 to 1.20), and 0.96 (range, 0.55 to 1.64), respectively. These findings support the feasibility of ex vivo expansion in a system free of nonhuman proteins of CD34(+)-derived progenitors obtained from the peripheral blood of patients who have received prior chemotherapy.
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PMID:Optimization of conditions for ex vivo expansion of CD34+ cells from patients with stage IV breast cancer. 752 42

Stromal cell lines derived from canine long-term bone marrow cultures (LTBMC) were characterized regarding the expression of growth factors and especially the localization of stem cell factor (SCF) (c-kit ligand). One cell line (DO64) was immortalized by transformation with a retroviral vector containing the open reading frames (ORFs) E6 and E7 of the human papilloma virus type 16 (HPV-16). Transfection did not change cellular characteristics but rendered the cell line more independent from culture conditions. The transformed line DO64 consisted mainly of fibroblast-like cells. In addition, some cells showed endothelial and some smooth-muscle cell features. Stromal cells expressed a broad spectrum of surface markers, including low levels of major histocompatibility-complex (MHC) class-II antigens. A new murine monoclonal antibody (MAb), RG7.6 (IgG1), specific for canine SCF, recognized the majority of fibroblast-like stromal cells. The staining pattern for SCF showed perinuclear and intracytoplasmic dense areas. Immunoelectron microscopy revealed the localization of SCF in secretory vesicles, the perivesicular cytoplasm, and bound to the cytoplasmatic membrane. RNA analysis showed that stromal cells transcribed, in addition to SCF, messages for granulocyte colony-stimulating factor (G-CSF), granulocyte-monocyte CSF (GM-CSF), interleukin-6 (IL-6), and transforming growth factor-beta (TGF-beta). In summary, we have established and characterized canine marrow-derived stromal cell lines, and using the new MAb RG7.6, we have localized SCF to cytoplasmatic vesicles as well as the membrane of stromal cells.
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PMID:Ultrastructural localization of stem cell factor in canine marrow-derived stromal cells. 752 83

Interleukin-6 (IL-6), leukemia inhibitory factor, oncostatin M, IL-11, and ciliary neurotrophic factor constitute the IL-6 family of cytokines and play important roles in hematopoiesis, immune response, and nervous system. The receptors for the IL-6 family of cytokines share gp130 through which signals are generated, although the cytoplasmic region of gp130 does not contain any catalytic domain. In this study we show that in addition to Jak family tyrosine kinase, the stimulation of gp130 by IL-6 plus soluble IL-6 receptor alpha induced the activation of Btk and Tec tyrosine kinases, whereas IL-3 and granulocyte colony-stimulating factor activated Tec but not Btk in a pro-B cell line. Furthermore, both Btk and Tec kinases were associated with gp130 without the ligand stimulation. Because Btk is a critical tyrosine kinase for B lymphopoiesis and Tec is considered to be involved in hematopoiesis, the results suggest the involvement of gp130-Btk-Tec signal pathway in early lymphohematopoiesis.
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PMID:Association and activation of Btk and Tec tyrosine kinases by gp130, a signal transducer of the interleukin-6 family of cytokines. 753 May

A new human carcinoma cell line, MISK81-5, was established from a metastatic lymph node of oral squamous cell carcinoma. Immunocytochemical and ultrastructural observations revealed an obvious epithelial origin of the cell line. Chromosome analysis revealed a hypertriploid karyotype with numerical and structural anomalies. MISK81-5 cells could form a tumor mass in the subcutaneous tissue of recipient BALB/c athymic mice only when coinjected with Matrigel. A stem cell assay revealed that conditioned medium (CM) of MISK81-5 contained granulocyte colony-stimulating factor (G-CSF) or interleukin-6 activity. Quantitation by ELISA disclosed a higher concentration of G-CSF in the CM of MISK81-5 than in the CM of other squamous and gastric carcinoma cell lines. The sMISK, that was derived from MISK81-5 as a subpopulation of the cell line having higher tumorigenicity, also showed a similar hematopoietic stimulating activity to that of MISK81-5. These characteristics of the MISK81-5 cell line and its subpopulation, sMISK will be useful for studying the biological behavior of oral squamous cell carcinomas and its relation to hematopoietic stimulating factors.
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PMID:New human oral squamous carcinoma cell line and its tumorigenic subline producing granulocyte colony-stimulating factor. 753 80

By use of the in vitro murine blast cell colony (Bl) assay system, Bl-constituting cells supported by interleukin-3 (IL-3), IL-3 + interleukin-6 (IL-6), IL-3 + granulocyte colony-stimulating factor (G-CSF) and IL-3 + interleukin-1 (IL-1) were replated and the frequencies of secondary (2nd) granulocyte/erythrocyte/macrophage/megakaryocyte (GEMM) colony and Bl progenitors were examined. According to the statistical method reported by Nakahata et al, the p values for the hemopoietic stem cells to self-renew were calculated and all cytokine groups produced similar p values ranging between 0.576 and 0.596. Further studies using IL-3-supported and IL-3 + G-CSF-supported Bl showed that the 2nd Bl progenitors could be produced even when there were more than 150 primary Bl-constituting cells per colony in the case of IL-3 + G-CSF, but no 2nd Bl progenitors were found in the case of IL-3. Their appearance was limited within the smaller primary Bl when supported by IL-3. Again there was a difference in the net product number of 2nd Bl progenitors, that is, the addition of G-CSF to the primary culture could produce around double the number of 2nd Bl progenitors. These data led us to hypothesize that synergistic factors could not modify the self-renewal probability, but maintained the self-renewal process for a longer period, in other words, for several cellular divisions.
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PMID:The self-renewal process of murine hemopoietic stem cells supported by interleukin-3 and the synergistic factors and the probability of its occurrence. 753 53

Interleukin-6 (IL-6) is a multifunctional cytokine that plays an important role in host defense. It has been predicted that IL-6 may fold as a 4 alpha-helix bundle structure with up-up-down-down topology. Despite a high degree of sequence similarity (42%) the human and mouse IL-6 polypeptides display distinct species-specific activities. Although human IL-6 (hIL-6) is active in both human and mouse cell assays, mouse IL-6 (mIL-6) is not active on human cells. Previously, we demonstrated that the 5 C-terminal residues of mIL-6 are important for activity, conformation, and stability (Ward LD et al., 1993, Protein Sci 2:1472-1481). To further probe the structure-function relationship of this cytokine, we have constructed several human/mouse IL-6 hybrid molecules. Restriction endonuclease sites were introduced and used to ligate the human and mouse sequences at junction points situated at Leu-62 (Lys-65 in mIL-6) in the putative connecting loop AB between helices A and B, at Arg-113 (Val-117 in mIL-6) at the N-terminal end of helix C, at Lys-150 (Asp-152 in mIL-6) in the connecting loop CD between helices C and D, and at Leu-178 (Thr-180 in mIL-6) in helix D. Hybrid molecules consisting of various combinations of these fragments were constructed, expressed, and purified to homogeneity. The conformational integrity of the IL-6 hybrids was assessed by far-UV CD. Analysis of their biological activity in a human bioassay (using the HepG2 cell line), a mouse bioassay (using the 7TD1 cell line), and receptor binding properties indicates that at least 2 regions of hIL-6, residues 178-184 in helix D and residues 63-113 in the region incorporating part of the putative connecting loop AB through to the beginning of helix C, are critical for efficient binding to the human IL-6 receptor. For human IL-6, it would appear that interactions between residues Ala-180, Leu-181, and Met-184 and residues in the N-terminal region may be critical for maintaining the structure of the molecule; replacement of these residues with the corresponding 3 residues in mouse IL-6 correlated with a significant loss of alpha-helical content and a 200-fold reduction in activity in the mouse bioassay. A homology model of mIL-6 based on the X-ray structure of human granulocyte colony-stimulating factor is presented.
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PMID:Structure-function analysis of human IL-6: identification of two distinct regions that are important for receptor binding. 753 47

The ifosfamide/carboplatin/etoposide (ICE) combination represents an active chemotherapy regimen across a wide variety of disease types. The most common limiting toxicity for all three of these agents individually and in combination is myelosuppression. Thus, this regimen represents an ideal model to evaluate the role of hematopoietic growth factor support in amelioration of hematologic toxicity, maintenance of dose intensity, and dose escalation. While chemotherapy strategies using colony-stimulating factors have abrogated neutropenia, cumulative thrombocytopenia is common with many chemotherapy regimens, including ICE chemotherapy. In preclinical and phase II trials, monotherapy with recombinant human interleukin-6 (IL-6) has demonstrated substantial thrombopoietic activity, but with little enhancement of neutrophil recovery. Thus, this study was designed to evaluate combination cytokine therapy with both recombinant IL-6 and granulocyte colony-stimulating factor (G-CSF) after ICE chemotherapy. Previously untreated patients with inoperable non-small cell lung cancer are eligible. Treatment includes two monthly cycles of ifosfamide 2,000 mg/m2 with mesna 1,600 mg/m2 intravenously on days 1, 2, and 3, carboplatin 350 mg/m2 intravenously on day 1 only, and etoposide 75 mg/m2 intravenously on days 1, 2, and 3. All patients then receive G-CSF at a dose of 5 micrograms/kg/d subcutaneously beginning on day 4 until a postnadir absolute neutrophil count of more than 10 x 10(9)/L. Cohorts of patients (n = 15) are randomized to receive 0, 1, 2.5, or 5 micrograms/kg/d of IL-6 subcutaneously on days 4 to 13 in successive cohorts. This study has now reached its target accrual in all cohorts. The final data analysis is in progress. It is hoped that this trial will define the safety and tolerability of the simultaneous administration of IL-6 and G-CSF following ICE chemotherapy in patients with non-small cell lung cancer. In addition, this trial should determine the biologic activity and hematopoietic recovery observed during the simultaneous administration of these two cytokines in this setting.
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PMID:The role of hematopoietic growth factors in support of ifosfamide/carboplatin/etoposide chemotherapy. 754 16

We have previously shown that early human CD34high hematopoietic progenitors are maintained quiescent in part through autocrine transforming growth factor-beta 1 (TGF-beta 1). We also demonstrated that, in the presence of interleukin-3, interleukin-6, granulocyte colony-stimulating factor, and erythropoietin, TGF-beta 1 antisense oligonucleotides or anti-TGF-beta serum have an additive effect with KIT ligand (Steel factor [SF]), which suggests that they control different pathways of regulation in these conditions. This finding also suggests that autocrine TGF-beta 1 might suppress c-kit expression in primitive human hematopoietic progenitors. We have now distinguished two subpopulations of CD34high cells. One subpopulation expresses a c-kit mRNA that can be downmodulated by exogenous TGF-beta 1 within 6 hours. Another subpopulation of early CD34high cells expresses a low or undetectable level of c-kit mRNA, but its expression can be upmodulated within 6 hours by anti-TGF-beta. These effects disappear 48 hours after induction and cannot be maintained longer than 72 hours, even if TGF-beta 1 or anti-TGF-beta serum are added every day. Similar kinetics, although delayed, are observed with KIT protein expression. On the contrary, no specific effect of TGF-beta 1 was observed on c-fms, GAPDH, and transferrin receptor gene expression in these early progenitors. These results clarify the complex interaction between TGF-beta 1 and SF in normal early hematopoietic progenitors. SF does not switch off the TGF-beta 1 inhibitory pathway. Autocrine TGF-beta 1 appears to maintain these cells in a quiescent state, suppressing cell division by downmodulating the receptor of SF, a key cytokine costimulator of early progenitors.
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PMID:Early CD34high cells can be separated into KIThigh cells in which transforming growth factor-beta (TGF-beta) downmodulates c-kit and KITlow cells in which anti-TGF-beta upmodulates c-kit. 754 39

In the osteopetrotic op/op mouse, the absence of macrophage colony-stimulating factor (M-CSF) prevents the growth of macrophages and osteoclasts and, consequently, bone resorption. In the present study, we investigated whether this deficiency in M-CSF production alters the production of cytokines in op/op bones. Calvariae of phenotypically normal (+/?) and op/op mice were stimulated in vitro with lipopolysaccharide or Pasteurella multocida toxin to produce cytokines. Interleukin-3 (IL-3) and granulocyte-macrophage colony-stimulating factor (GM-CSF) synthesis was the same both in calvaria from osteopetrotic and phenotypically normal animals. However, the production of granulocyte colony-stimulating factor (G-CSF), interleukin-6 (IL-6), and tumor necrosis factor-alpha (TNF alpha) was lower in calvaria from op/op animals than was the case in +/? calvaria. Thus, the lack of biologically active M-CSF causes defects which are not compensated by cells independent of M-CSF.
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PMID:Cytokine production by calvariae of osteopetrotic mice. 757 58

Endothelial cells are a major component of the bone marrow (BM) microenvironment that regulate the trafficking and homing of hematopoietic progenitor and stem cells. In this paper, we provide evidence that BM endothelial cells (BMECs) also support multilineage hematopoiesis by elaboration of soluble cytokines. Hematopoietic progenitor cells incubated in direct contact with BMEC monolayers, or physically separated by microporous membrane, expanded five-fold to sevenfold at 7 days, in the absence of exogenous cytokines. Flow cytometric analysis of proliferating progenitor cells grown in the presence of BMEC monolayers showed that by day 14 of coculture, 70% to 80% of hematopoietic cells were myeloid, expressing CD15 or CD14, and 14% to 19% were megakaryocytic, expressing GPIIb/IIIa or GPIb. CD34+ cells derived from umbilical cord blood, cultured in the upper chamber of transwell culture plates, as well as the cells grown in direct contact with BMEC monolayers, generated progenitors for up to 70 days. Unstimulated BMEC monolayers constitutively produce interleukin-6, Kit-ligand, granulocyte colony-stimulating factor, and granulocyte macrophage colony-stimulating factor. These data suggest that BMEC regulate proliferation of hematopoietic progenitor cells and long-term culture initiating cells by elaboration of lineage-specific cytokines.
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PMID:Human bone marrow microvascular endothelial cells support long-term proliferation and differentiation of myeloid and megakaryocytic progenitors. 757 38


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