Biomedical subjects

N Janakiraman

Publications and source records attributed to N Janakiraman.

At least 19 recordsLinked to original sources

PubMed2002

Human marrow stromal cell therapy for stroke in rat: neurotrophins and functional recovery.

OBJECTIVE: To test the effect of i.v.-injected human bone marrow stromal cells (hMSC) on neurologic functional deficits after stroke in rats. METHODS: Rats were subjected to transient middle cerebral artery occlusion and IV injected with 3 x 10(6) hMSC 1 day after stroke. Functional outcome was measured before and 1, 7, and 14 days after stroke. Mixed lymphocyte reaction and the development of cytotoxic T lymphocytes measured the immune rejection of hMSC. A monoclonal antibody specific to human cellular nuclei (mAb1281) was used to identify hMSC and to measure neural phenotype. ELISA analyzed neurotrophin levels in cerebral tissue from hMSC-treated or nontreated rats. Bromodeoxyuridine injections were used to identify newly formed cells. RESULTS: Significant recovery of function was found in rats treated with hMSC at 14 days compared with control rats with ischemia. Few (1 to 5%) hMSC expressed proteins phenotypic of brain parenchymal cells. Brain-derived neurotrophic factor and nerve growth factor significantly increased, and apoptotic cells significantly decreased in the ischemic boundary zone; significantly more bromodeoxyuridine-reactive cells were detected in the subventricular zone of the ischemic hemisphere of rats treated with hMSC. hMSC induced proliferation of lymphocytes without the induction of cytotoxic T lymphocytes. CONCLUSION: Neurologic benefit resulting from hMSC treatment of stroke in rats may derive from the increase of growth factors in the ischemic tissue, the reduction of apoptosis in the penumbral zone of the lesion, and the proliferation of endogenous cells in the subventricular zone.

Animals↗

PubMed2001

Immunomodulatory activity of resveratrol: suppression of lymphocyte proliferation, development of cell-mediated cytotoxicity, and cytokine production.

trans-Resveratrol, a phytoalexin found in grapes, wine, and other plant products, has been shown to have anti-inflammatory, antioxidant, and antitumor activities. Many of these beneficial effects of resveratrol require participation of the cells of the immune system; however, the effect of resveratrol on the development of immunological responses remains unknown. We have investigated the effect of resveratrol on mitogen/antigen-induced proliferation of splenic lymphocytes, induction of cytotoxic T lymphocytes (CTLs) and lymphokine activated killer (LAK) cells, and the production of the cytokines interferon (IFN)-gamma, interleukin (IL)-2, tumor necrosis factor (TNF)-alpha, and IL-12. We found that mitogen-, IL-2-, or alloantigen-induced proliferation of splenic lymphocytes and the development of antigen-specific CTLs were suppressed significantly at 25-50 microM resveratrol. The generation of LAK cells at similar concentrations was less sensitive to the suppressive effect of resveratrol. The suppression of cell proliferation and CTL generation by resveratrol was not only reversible, but in some cases the response (mitogen/IL-2-induced proliferation and CTL generation) was actually enhanced following pretreatment of cells with resveratrol. Resveratrol also inhibited the production of IFN-gamma and IL-2 by splenic lymphocytes, and the production of TNF-alpha and IL-12 by peritoneal macrophages. The inhibition of cytokine production by resveratrol was irreversible. Further, resveratrol blocked the activation of the transcription factor NF-kappaB without affecting basal NF-kappaB activity. The latter result suggests that resveratrol inhibits cell proliferation, cell-mediated cytotoxicity, and cytokine production, at least in part through the inhibition of NF-kappaB activation.

Adjuvants, Immunologic↗

PubMed2001

IL-12 gene therapy of leukemia with hematopoietic progenitor cells without the toxicity of systemic IL-12 treatment.

We have previously shown that the myeloid progenitor cell line 32Dc13 transduced with mIL-12 cDNAs (32DIL-12 cells) induces IFN-gamma and NK-cell-mediated cytotoxicity in vivo. Since systemic therapy with recombinant IL-12 protein has been shown to produce moderate to severe toxic side effects we examined whether IL-12 gene therapy with hematopoietic progenitor cells also induces systemic toxicities that are commonly associated with the administration of rIL-12 protein. Injection of large doses of IL-12 secreting 32DIL-12 cells (5 to 6 x 10(7) cells) significantly reduced mortality in mice injected with a lethal dose of 32Dp210 myeloid leukemia cells. More importantly, injection of similar doses of transduced cells failed to reduce body weight significantly or produce other visible signs of toxicity, i.e., fur ruffling or lethargy. There was no evidence of hematologic or hematopoietic toxicity resulting from the injection of transduced cells. In addition, microscopic examination of liver, kidney, lung, and intestine of mice injected with transduced cells revealed the absence of tissue necrosis or inflammatory response in any of these organs. Finally, 32DIL-12 cells were not found to interfere with the engraftment of syngeneic bone marrow transplant or the hematopoietic reconstitution of irradiated mice. These results demonstrate that IL-12 gene therapy with hematopoietic progenitor cells is nontoxic and provide a rationale for exploring the feasibility of treating minimal residual leukemia with IL-12 gene therapy.

Animals↗

PubMed2001

Therapy-related myelodysplastic syndrome (t-MDS) in a patient with anaplastic astrocytoma: successful treatment with allogeneic bone marrow transplant.

OBJECTIVE: and importance Therapy-related myelodysplastic syndrome (t-MDS) is a rare and typically fatal complication of therapy for cancer, including brain tumors. We report successful therapy of t-MDS that developed after treatment for an anaplastic astrocytoma. CLINICAL PRESENTATION: t-MDS developed four and one-half years after successful therapy (resection, radiation and chemotherapy) administered for a cerebral anaplastic astrocytoma in a 34-year-old patient. INTERVENTION: The patient was treated with allogeneic bone marrow transplant (BMT) for t-MDS. CONCLUSION: She is alive three years after BMT with no evidence of brain tumor and in complete remission from t-MDS. To our knowledge, this is the first report of allogeneic BMT administered for t-MDS in an adult brain tumor patient. Clinicians must be alert to the development of t-MDS following chemotherapy for brain tumors and initiate appropriate treatment promptly.

Adult↗

PubMed2000

Resveratrol selectively inhibits leukemia cells: a prospective agent for ex vivo bone marrow purging.

Ex vivo purging of contaminating tumor cells may reduce the incidence of relapse in patients undergoing bone marrow transplantation. In this study we demonstrate that resveratrol, a phytoalexin with anti-oxidant and chemopreventive activity, exhibits anti-leukemic activity against mouse (32Dp210, L1210) and human (U937, HL-60) leukemic cell lines by inhibiting cell proliferation. Long-term exposure to resveratrol also inhibits the clonal growth of normal hematopoietic progenitor cells but at a higher IC50 of resveratrol than that for most of the leukemia cell lines tested. The inhibitory effect of resveratrol on hematopoietic progenitors is partially reversible, whereas the effect on leukemia cells is largely irreversible. The inhibition of leukemia cells by resveratrol involves nucleosomal DNA fragmentation (apoptosis). On the other hand, resveratrol does not induce or enhance spontaneously occurring apoptotic death in normal hematopoietic progenitor cells. In vivo experiments performed with untreated and resveratrol-treated bone marrow showed comparable hematopoietic reconstitution in lethally irradiated mice (10 Gy) as determined by survival, hematologic recovery, and the number of hematopoietic progenitor cells present in the marrow of reconstituted animals. Taken together, these results indicate the potential use of resveratrol for ex vivo pharmacological purging of leukemia cells from bone marrow autografts without significant loss in the hematopoietic activity of progenitor cells.

Animals↗

PubMed2000

Interleukin-12 (IL-12) gene therapy of leukemia: immune and anti-leukemic effects of IL-12-transduced hematopoietic progenitor cells.

Recombinant interleukin-12 (rlL-12) is a potent immunomodulatory cytokine that has been shown to exert strong antitumoral and antimetastatic activity against several mouse tumors grown as solid lesions. The therapeutic efficacy of rIL-12 against hematological tumors and the transfer of IL-12 genes into hematopoietic progenitor cells to deliver IL-12 to the bone marrow (BM) to treat residual leukemia has not been studied adequately. We have investigated the retroviral-mediated transduction of hematopoietic progenitor cells with IL-12 genes and the in vivo anti-leukemic activity of transduced cells against the murine myeloid leukemia cell line 32Dp210. We were able to efficiently transduce the IL-3-dependent 32Dc13 myeloid progenitor cell line and primary hematopoietic progenitor cells using an MFG-based polycistronic retroviral vector containing the cDNAs of p35 and p40 murine IL-12 genes. 32Dc13 myeloid progenitor cells expressing IL-12 genes (32DIL-12 cells) have stably secreted biologically active murine IL-12 for >9 months. Mice transplanted with 32DIL-12 cells transiently express the transgene in the BM and spleen, which is associated with a rapid elevation of interferon-gamma (IFN-gamma) in the circulation and with secretion of IFN-gamma by spleen cells in vitro. In addition, spleen and BM cells of mice injected with 32DIL-12 cells readily acquire the capacity to lyse natural killer cell-sensitive YAC-1 target cells and 32Dp210 myeloid leukemia cells. Furthermore, whereas mice challenged with leukemia cells suffered 100% mortality within 14 days, approximately 40% of mice coinjected with 32Dp210 leukemia cells and 32DIL-12 progenitor cells exhibited long-term, leukemia-free survival (>60 days). This study demonstrates that IL-12 can be stably expressed in hematopoietic cells; in addition, when transplanted, transduced cells induce IFN-gamma production and activation of natural killer cells, both of which may be involved in inhibiting the progression of leukemia in vivo.

Animals↗

PubMed1999

Extended Rituximab (anti-CD20 monoclonal antibody) therapy for relapsed or refractory low-grade or follicular non-Hodgkin's lymphoma.

BACKGROUND: Rituximab is a chimeric monoclonal antibody directed against the B-cell CD20 antigen which has been utilized for therapy of B-cell non-Hodgkin's lymphoma (NHL). A previous clinical trial demonstrated that treatment with four weekly doses of 375 mg/m2 of Rituximab in patients with relapsed or refractory low-grade or follicular B-cell non-Hodgkin's lymphoma was well tolerated and had significant clinical activity. PATIENTS AND METHODS: To assess the safety and efficacy of Rituximab treatment, an open-label, single-arm, multi-center, phase II study of eight consecutive weekly infusions of 375 mg/m2 Rituximab in patients with low-grade or follicular B-cell NHL who had relapsed or had failed primary therapy was conducted. Thirty-seven patients with a median age of 55 years were treated. RESULTS: Grade 1 or 2 adverse events were the majority of reported toxicities and occurred most frequently with the first infusion, decreasing with subsequent infusions. No patients developed a host antibody response (HACA) to Rituximab. The mean serum immunoglobulin levels for IgG, IgA, and IgM stayed within the normal range throughout the study. The majority of patients who were bcl-2 positive at baseline in peripheral blood became bcl-2 negative during treatment and remained negative at the time of B-cell recovery. In the 37 intent-to-treat patients, 5 (14%) had a complete response and 16 (43%) had a partial response for an overall response rate of 57%. Of 35 evaluable patients, 21 (60%) responded to treatment (14% CR and 46% PR). In responders, the median time to progression (TTP) and the median response duration have not been reached after 19.4+ months and 13.4+ months, respectively. CONCLUSIONS: The safety profile and efficacy achieved in this pilot study of extended treatment with Rituximab compares favorably with those seen with four weekly doses. Further studies are warranted to investigate whether this or other extended Rituximab schedules will result in increased efficacy in all or in certain subgroups of patients with low-grade or follicular NHL.

Adult↗

PubMed1999

Enhanced assessment of allogeneic bone marrow transplant engraftment using automated fluorescent-based typing.

Traditional qualitative gel electrophoresis approaches lack accurate' and quantitative assessment of mixed chimerism in BMT patients. The likelihood of informative markers is greatly increased using simultaneous amplification of 10 highly polymorphic loci with fluorescent-labeled primers in an automated DNA sequencer. This allows for more precise interpretation of mixed chimerism with a detection level approximating 1%. To evaluate this approach to quantitative assessment of chimeric populations we mixed varying proportions of samples from two unrelated donors, by either mixing aliquots of DNA isolated from whole blood, or by first counting the white blood cells and mixing varying proportions of cells together prior to DNA isolation. The allelic-peak area ratios were identical to allelic-peak height ratios and corresponded to the proportion of mixed DNA, regardless of the method used to create the mixture. Formulas to provide routine, consistent and quantitative interpretation of mixed chimerism are presented. We analyzed 14 allograft recipients and one autologous BMT patient with transfusion-induced GVHD. In all cases, at least four out of nine markers were informative. Inter-laboratory concordance of results was also obtained with an eight marker panel using an automated Alf-Express. In conclusion, the automated DNA fluorescent-labeled primer approach using an eight to 10 marker panel is quantitative and informative in assessing chimerism.

Alleles↗

PubMed1999

TNF-alpha gene therapy with myeloid progenitor cells lacks the toxicities of systemic TNF-alpha therapy.

We examined the antileukemic activity and the toxicity of HPC transduced with human tumor necrosis factor (TNF) cDNA. Both clonal (32Dcl3) and BM-derived primary hematopoietic progenitors (BM-Prog) expressing hTNF-alpha gene (32DTNF-alpha and BMTNF-alpha cells, respectively) inhibited the development of leukemia in mice with a small dose of 32Dp210 cells, a myeloid leukemia cell line. Whether the trans-gene expressing 32DTNF-alpha cells produce toxicities commonly associated with systemic TNF-alpha therapy was determined by examining the effect of TNF-alpha-secreting progenitor cells on body weight, tissue histology, growth of HPC, and engraftment of BMT. Administration of a low or high dose of TNF-alpha-secreting 32DTNF-alpha cells to mice failed to produce loss in body weight, a measure of TNF-alpha-related cachexia. There was also no evidence of tissue necrosis or mononuclear cell (MNC) infiltration in lung, liver, kidney, or intestine of mice injected with transduced progenitor cells. Furthermore, 32DTNF-alpha cells showed no effect on the clonal growth of HPC in colony-forming assays or loss of cellularity in BM, spleen, or blood. Finally, TNF-alpha-secreting cells were found not to interfere with the engraftment of BM transplant and hematopoietic reconstitution thereafter. We conclude from these findings that unlike systemic administration of TNF-alpha, TNF-alpha gene therapy with transduced HPC is nontoxic and may have a role in eradicating residual leukemia after BMT.

Animals↗

PubMed1999

Phase I/II trial of IDEC-Y2B8 radioimmunotherapy for treatment of relapsed or refractory CD20(+) B-cell non-Hodgkin's lymphoma.

PURPOSE: Yttrium-90 ibritumomab tiuxetan (IDEC-Y2B8) is a murine immunoglobulin G1 kappa monoclonal antibody that covalently binds MX-DTPA (tiuxetan), which chelates the radioisotope yttrium-90. The antibody targets CD20, a B-lymphocyte antigen. A multicenter phase I/II trial was conducted to compare two doses of unlabeled rituximab given before radiolabeled antibody, to determine the maximum-tolerated single dose of IDEC-Y2B8 that could be administered without stem-cell support, and to evaluate safety and efficacy. PATIENTS AND METHODS: Eligible patients had relapsed or refractory (two prior regimens or anthracycline if low-grade disease) CD20(+) B-cell low-grade, intermediate-grade, or mantle-cell non-Hodgkin's lymphoma (NHL). There was no limit on bulky disease, and 59% had at least one mass > or = 5 cm. RESULTS: The maximum-tolerated dose was 0.4 mCi/kg IDEC-Y2B8 (0.3 mCi/kg for patients with baseline platelet counts 100 to 149,000/microL). The overall response rate for the intent-to-treat population (n = 51) was 67% (26% complete response [CR]; 41% partial response [PR]); for low-grade disease (n = 34), 82% (26% CR; 56% PR); for intermediate-grade disease (n = 14), 43%; and for mantle-cell disease (n = 3), 0%. Responses occurred in patients with bulky disease (> or = 7 cm; 41%) and splenomegaly (50%). Kaplan-Meier estimate of time to disease progression in responders and duration of response is 12.9+ months and 11.7+ months, respectively. Adverse events were primarily hematologic and correlated with baseline extent of marrow involvement with NHL and baseline platelet count. One patient (2%) developed an anti-antibody response (human antichimeric antibody/human antimouse antibody). CONCLUSION: These phase I/II data demonstrate that IDEC-Y2B8 radioimmunotherapy is a safe and effective alternative for outpatient therapy of patients with relapsed or refractory NHL. A phase III study is ongoing.

Adolescent↗

PubMed1999

Radioimmunotherapy of relapsed non-Hodgkin's lymphoma with zevalin, a 90Y-labeled anti-CD20 monoclonal antibody.

Approximately 55,400 new cases of non-Hodgkin's lymphoma (NHL) are diagnosed each year, with the overall prevalence of the disease now estimated to be 243,000. Until recently, treatment alternatives for advanced disease included chemotherapy with or without external beam radiation. Based on the results of several clinical trials, the chimeric monoclonal antibody Rituximab has now been approved by the United States Food and Drug Administration as a treatment for patients with relapsed or refractory, low-grade or follicular, B-cell NHL. Several other monoclonal antibodies in conjugated and unconjugated forms have been evaluated in the treatment of NHL. Ibritumomab, the murine counterpart to Rituximab, radiolabeled with 90Y (Zevalin), is presently being evaluated in clinical trials. The success of radioimmunotherapy is dependent upon the appropriate choice of antibody, isotope, and chelator-linker. The Ibritumomab antibody targets the CD20 antigen. The antibody is covalently bound to the chelator-linker tiuxetan (MX-DTPA), which tightly chelates the isotope 90Y. To date, two Phase I/II Zevalin clinical trials have been completed in patients with low-grade, intermediate-grade, and mantle cell NHL. The overall response rate was 64% in the first trial and 67% in the later trial. Phase II and III trials are ongoing.

Antibodies, Monoclonal↗

PubMed1998

Nonselective inhibition of proliferation of transformed and nontransformed cells by the anticancer agent curcumin (diferuloylmethane).

We have investigated the antiproliferative effect of curcumin, an antitumor agent with antioxidant and anti-inflammatory properties, against a variety of transformed and nontransformed cell types. At equimolar concentrations ranging from 6.25 to 50 microM, curcumin inhibited DNA synthesis, as revealed by 3H-incorporation, in five leukemia lines, three nontransformed hematopoietic progenitor cell populations, and four nontransformed fibroblastic cell lines in a concentration-dependent manner. Curcumin also inhibited the cellular growth of both transformed and nontransformed cells in clonogenic assays. Without discriminating between transformed or nontransformed cells, the inhibition of cell proliferation by curcumin was not always associated with programmed cell death. These findings have implications for developing curcumin-based anticancer and anti-inflammation therapies.

Animals↗

PubMed1998

Aspergillus fungal mass detected by transesophageal echocardiography.

Cardiac fungal infections have become more prevalent and are being diagnosed with increasing frequency. The most common infective organism is Candida albicans, followed by Aspergillus fumigatus and Cryptococcus. Cardiac involvement is usually associated with endocarditis, myocarditis, pericarditis, or intracardiac fungal mass. Early diagnosis is imperative, as these patients have poor outcome once there is cardiac involvement. In this report we describe a patient in whom an intracardiac mass was detected with transesophageal echocardiography and confirmed to be aspergillus fungal ball at surgery.

Adult↗

PubMed1998

Antileukemic activity of TNF-alpha gene therapy with myeloid progenitor cells against minimal leukemia.

Tumor necrosis factor-alpha (TNF-alpha) has exhibited antitumor activity against a variety of tumors in rodents and human tumor xenografts in nude mice, but it has been only marginally effective in cancer patients because of dose-limiting toxicity associated with systemic TNF-alpha therapy. To circumvent toxicity and to test the antileukemic activity against quantitated minimal leukemia, we have cloned human TNF-alpha (HuTNF-alpha) gene in an advanced myeloid progenitor cell line. 32Dcl3 myeloid progenitor cells transfected with HuTNF-alpha cDNA by the retroviral supernatant infection method stably express HuTNF-alpha gene and secrete substantial amounts of HuTNF-alpha. When injected i.v. into irradiated mice, transduced cells could be detected in the marrow but not in spleen or liver 10-12 days later. Injection of 5 x 10(6) transduced cells produced no obvious symptoms of TNF-alpha toxicity (i.e., weight loss, cachexia, or fever) suggesting that TNF-alpha producing cells are well tolerated by the recipient mice. Coinjection of 5 x 10(6) transduced cells and 10(2) or 10(3) 32Dp210 leukemia (BCR/ABL+) cells resulted in inhibition of leukemia development by 10(2) but not 10(3) 32Dp210 cells. An equal dose of nontransduced 32Dcl3 cells was ineffective in inhibiting leukemia progression by 10(2) 32Dp210 cells. Mice that rejected leukemia were BCR/ABL oncogene negative 8 weeks after leukemia cell injection. These data demonstrate the potential for TNF-alpha gene therapy for destroying residual leukemia, without the toxicity of systemic TNF-alpha therapy, following cytoreductive therapy and bone marrow transplant.

3T3 Cells↗

PubMed1997

IDEC-C2B8 (Rituximab) anti-CD20 monoclonal antibody therapy in patients with relapsed low-grade non-Hodgkin's lymphoma.

IDEC-C2B8 is a chimeric monoclonal antibody (MoAb) directed against the B-cell-specific antigen CD20 expressed on non-Hodgkin's lymphomas (NHL). The MoAb mediates complement and antibody-dependent cell-mediated cytotoxicity and has direct antiproliferative effects against malignant B-cell lines in vitro. Phase I trials of single doses up to 500 mg/m2 and 4 weekly doses of 375 mg/m2 showed clinical responses with no dose-limiting toxicity. We conducted a phase II, multicenter study evaluating four weekly infusions of 375 mg/m2 IDEC-C2B8 in patients with relapsed low-grade or follicular NHL (Working Formulation groups A-D). Patients were monitored for adverse events, antibody pharmacokinetics, and clinical response. Thirty-seven patients with a median age of 58 years (range, 29 to 81 years) were treated. All patients had relapsed after chemotherapy (median of 2 prior regimens) and 54% had failed aggressive chemotherapy. Infusional side effects (grade 1-2) consisting of mild fever, chills, respiratory symptoms, and occasionally hypotension were observed mostly with the initial antibody infusion and were rare with subsequent doses. Peripheral blood B-cell depletion occurred rapidly, with recovery beginning 6 months posttreatment. There were no significant changes in mean IgG levels and infections were not increased over what would be expected in this population. Clinical remissions were observed in 17 patients (3 complete remissions and 14 partial remissions), yielding an intent to treat response rate of 46%. The onset of these tumor responses was as soon as 1 month posttreatment and reached a maximum by 4 months posttreatment. In the 17 responders, the median time to progression was 10.2 months (5 patients exceeding 20 months). Likelihood of tumor response was associated with a follicular histology, with the ability to sustain a high serum level of antibody after the first infusion, and with a longer duration of remission to prior chemotherapy. One patient developed a detectable but not quantifiable immune response to the antibody that had no clinical significance. IDEC-C2B8 in a dose of 375 mg/m2 weekly for 4 weeks has antitumor activity in patients with relapsed low-grade or follicular NHL. Results with this brief, outpatient treatment compare favorably with results with standard chemotherapy, and IDEC-C2B8 has a better safety profile. Further studies evaluating IDEC-C2B8 in other types of lymphoma either alone or combined with chemotherapy are warranted.

Adult↗

PubMed1997

Transplantation in patients with multiple myeloma: a multicenter comparative analysis of peripheral blood stem cell and allogeneic transplant.

We performed a multicenter comparative analysis of autologous peripheral blood stem cell transplantation (PBSCT) and allogeneic bone marrow transplantation (alloBMT) in multiple myeloma. Forty-eight consecutive patients received either PBSCT (24 patients) or alloBMT (24 patients) at one of three institutions in the study group. Preparatory regimens consisted of melphalan and total body irradiation (TBI) or melphalan alone in the PBSCT group. The alloBMT group received one of four regimens: cyclophosphamide and TBI; cyclophosphamide, VP-16 and 1,3-bis(2-chloroethyl)-1-nitrosourea (CVB); busulfan and cyclophosphamide (BU/CY) and total marrow irradiation (TMI); or melphalan and TBI. Procedure-related mortality was 12.5% for the PBSCT group and 25% for the alloBMT group. With a median follow-up for survivors in the PBSCT and alloBMT groups of 11 months (range, 4-46) and 15 months (range, 2-84 months), respectively, there was no significant difference in median overall survival (33.5 versus 38.6 months, p = 0.7637) or event-free survival (16.7 versus 31 months, p = 0.8450). There was, however, a plateau in survival at 40% in the alloBMT group. No plateau in survival was seen in the PBSCT group. Clinical relapses occurred as late as 39 months posttransplant. Patients have survived up to 28 months postrelapse.

Adult↗

PubMed1997

Curcumin, a compound with anti-inflammatory and anti-oxidant properties, down-regulates chemokine expression in bone marrow stromal cells.

Chemotactic cytokines or chemokines play an important role in the regulation of myelopoiesis. Since the production of chemokines and colony stimulating factors (CSFs) by bone marrow stromal cells requires inflammatory conditions, we investigated the effect of curcumin, an agent with anti-inflammatory and anti-oxidant activities, on the expression of monocyte chemoattractant protein-1 (MCP-1 or MCP-1/JE) and interferon inducible protein-10kD (IP-10) in mouse bone marrow stromal cell line +/+-1.LDA11. Both chemokines are readily expressed in stromal cells after stimulation with pro-inflammatory interleukin-1alpha (IL-1alpha), interferon-gamma (IFN-gamma), tumor necrosis factor-alpha (TNF-alpha), and endotoxin lipopolysaccharide (LPS). Curcumin attenuates the levels of MCP-1/JE and IP-10 mRNA expression by all of these stimulatory agents. A detailed analysis of the regulatory effects of curcumin on chemokine expression by IL-1alpha was performed. Curcumin inhibits both chemokine mRNAs in a dose- and time-dependent manner. The suppressive effect of curcumin on both mRNAs is reversible with complete recovery from suppression within 24 hours after removal of curcumin. The suppression of mRNA by curcumin is dependent on de novo synthesis of an intermediary protein(s), since suppression is abrogated by concomitant treatment with cycloheximide (CHX). Destabilization of mRNA transcripts is not the mechanism by which curcumin lowers the levels of mRNA; however, transcripts formed in the presence of curcumin are more stable, as indicated by their slower degradation kinetics. Run-on transcriptional assays demonstrate that curcumin inhibits the transcriptional activity of both genes. Finally, the attenuation of chemokine gene expression is associated with decreased production of chemotactic activity. Together, these findings indicate that while curcumin may post-transcriptionally stabilize mRNA transcripts formed in its presence, the overall reduction in mRNA levels by curcumin is mediated by inhibition of the transcription of chemokine genes.

Animals↗

PubMed1996

IL-4 upregulates IL-1-induced chemokine gene expression in bone marrow stromal cells by enhancing NF-kB activation.

Bone marrow stromal cells play a critical role in the proliferation and differentiation of hematopoietic stem and progenitor cells by secreting numerous hematopoietic growth factors and colony-stimulating factors (CSFs). We have previously reported that monocyte chemotactic protein-1 (MCP-1 or MCP-1/JE) and interferon-inducible protein 10 KD (IP-10) are both induced in murine bone marrow stromal cell line +/(+)-1.LDA11 upon stimulation with various inflammatory agents, including IL-1 alpha, IFN-gamma, TNF-alpha, or LPS. In addition, the expression of MCP-1/JE and IP-10 mRNA by these inducers is potentiated by IL-4 and TGF-beta 1. In the present study we have investigated the mechanism of IL-4-mediated upregulation of MCP-1/JE gene expression. Our results of nuclear run-on experiments show that IL-4 enhances the IL-1-induced transcription of MCP-1/JE gene. Because the transcription of genes is regulated by DNA binding nuclear factors and binding sites for transcription factors AP-1 and SP-1, and NF-kB in the enhancer region of MCP-1/JE have been demonstrated, we examined the effect of IL-4 on the levels of these factors in stromal cells stimulated with IL-1. Whereas AP-1 and SP-1 are constitutively expressed in stromal cells, NF-kB is detected only after stimulation with IL-1. Furthermore, while unable to induce the activation of NF-kB alone, IL-4 enhanced the activation of NF-kB by IL-1. Taken together, these data suggest that upregulation of NF-kB may be the mechanism by which IL-4 increases the transcription of MCP-1/JE gene resulting in overabundance of the chemokine mRNA.

Animals↗