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J C Renauld

Publications and source records attributed to J C Renauld.

At least 19 recordsLinked to original sources

Cutting edge: STAT activation by IL-19, IL-20 and mda-7 through IL-20 receptor complexes of two types.

IL-10-related cytokines include IL-20 and IL-22, which induce, respectively, keratinocyte proliferation and acute phase production by hepatocytes, as well as IL-19, melanoma differentiation-associated gene 7, and AK155, three cytokines for which no activity nor receptor complex has been described thus far. Here, we show that mda-7 and IL-19 bind to the previously described IL-20R complex, composed by cytokine receptor family 2-8/IL-20Ralpha and DIRS1/IL-20Rbeta (type I IL-20R). In addition, mda-7 and IL-20, but not IL-19, bind to another receptor complex, composed by IL-22R and DIRS1/IL20Rbeta (type II IL-20R). In both cases, binding of the ligands results in STAT3 phosphorylation and activation of a minimal promoter including STAT-binding sites. Taken together, these results demonstrate that: 1) IL-20 induces STAT activation through IL-20R complexes of two types; 2) mda-7 and IL-20 redundantly signal through both complexes; and 3) IL-19 signals only through the type I IL-20R complex.

Carrier Proteins↗

Cloning and characterization of IL-22 binding protein, a natural antagonist of IL-10-related T cell-derived inducible factor/IL-22.

The class II cytokine receptor family includes the receptors for IFN-alphabeta, IFN-gamma, IL-10, and IL-10-related T cell-derived inducible factor/IL-22. By screening genomic DNA databases, we identified a gene encoding a protein of 231 aa, showing 33 and 34% amino acid identity with the extracellular domains of the IL-22 receptor and of the IL-20R/cytokine receptor family 2-8, respectively, but lacking the transmembrane and cytoplasmic domains. A lower but significant sequence identity was found with other members of this family such as the IL-10R (29%), cytokine receptor family 2-4/IL-10Rbeta (30%), tissue factor (26%), and the four IFN receptor chains (23-25%). This gene is located on chromosome 6q24, at 35 kb from the IFNGR1 gene, and is expressed in various tissues with maximal expression in breast, lungs, and colon. The recombinant protein was found to bind IL-10-related T cell-derived inducible factor/IL-22, and to inhibit the activity of this cytokine on hepatocytes and intestinal epithelial cells. We propose to name this natural cytokine antagonist IL-22BP for IL-22 binding protein.

Amino Acid Sequence↗

Interleukin 9 induces expression of three cytokine signal inhibitors: cytokine-inducible SH2-containing protein, suppressor of cytokine signalling (SOCS)-2 and SOCS-3, but only SOCS-3 overexpression suppresses interleukin 9 signalling.

Interleukin 9 (IL-9) is a cytokine preferentially produced by T helper type 2 lymphocytes and active on various cell types such as T- and B-lymphocytes, mast cells and haemopoietic progenitors. The IL-9 receptor (IL-9R) belongs to the haemopoietic receptor superfamily and its signal transduction involves mainly the Janus kinase/signal transducer and activator of transcription (JAK/STAT) pathway. Here we studied the implication of a novel family of suppressors of cytokine signalling (called CIS, for cytokine-inducible SH2-containing protein, and SOCS, for suppressor of cytokine signalling) in IL-9 signal attenuation. In BW5147 T-cell lymphoma, IL-9 induced the rapid expression of CIS, SOCS-2 and SOCS-3 with a peak after 2 h of stimulation. Using IL-9R mutants, we showed that STAT activation is required for CIS/SOCS induction: CIS and SOCS-2 expression was induced either via STAT1 and/or STAT3 or via STAT5 but only STAT1 and/or STAT3 were involved in SOCS-3 expression. The effect of these three proteins on IL-9 signal transduction was assessed by transient transfection in HEK-293 cells expressing the components of the IL-9 signalling pathway and a STAT-responsive reporter construct. These experiments showed that only SOCS-3 is able to inhibit IL-9-induced signal transduction; neither CIS nor SOCS-2 exerted any effect. Stable transfection of CIS and SOCS-3 in BW5147 lymphoma cells showed that only overexpression of SOCS-3 had an inhibitory activity on STAT activation, gene induction and the anti-apoptotic activity of IL-9. By contrast, CIS failed to affect the IL-9 response.

Blotting, Western↗

New insights into the role of cytokines in asthma.

Asthma is a triad of intermittent airway obstruction, bronchial smooth muscle cell hyperreactivity to bronchoconstrictors, and chronic bronchial inflammation. From an aetiological standpoint, asthma is a heterogeneous disease, but often appears as a form of immediate hypersensitivity. Many patients with asthma have other manifestations of atopy, such as rhinitis or eczema. Even among non-atopic patients with asthma, the pathophysiology of airway constriction is similar, raising the hypothesis that alternative mechanisms of mast cell degranulation may underlie the disease. The primary inflammatory lesion of asthma consists of accumulation of CD4(+) T helper type 2 (TH2) lymphocytes and eosinophils in the airway mucosa. TH2 cells orchestrate the asthmatic inflammation through the secretion of a series of cytokines, particularly interleukin 4 (IL-4), IL-13, IL-5, and IL-9. IL-4 is the major factor regulating IgE production by B cells, and is required for optimal TH2 differentiation. However, blocking IL-4 is not sufficient to inhibit the development of asthma in experimental models. In contrast, inhibition of IL-13, another TH2 cytokine whose signal transduction pathway overlaps with that of IL-4, completely blocks airway hyperreactivity in mouse asthma models. IL-5 is a key factor for eosinophilia and could therefore be responsible for some of the tissue damage seen in chronic asthma. IL-9 has pleiotropic activities on allergic mediators such as mast cells, eosinophils, B cells and epithelial cells, and might be a good target for therapeutic interventions. Finally, chemokines, which can be produced by many cell types from inflamed lungs, play a major role in recruiting the mediators of asthmatic inflammation. Genetic studies have demonstrated that multiple genes are involved in asthma. Several genome wide screens point to chromosome 5q31--33 as a major susceptibility locus for asthma and high IgE values. This region includes a cluster of cytokine genes, and genes encoding IL-3, IL-4, IL-5, IL-9, IL-13, granulocyte macrophage colony stimulating factor, and the beta chain of IL-12. Interestingly, for some of these cytokines, a linkage was also established between asthma and their receptor. Another susceptibility locus has been mapped on chromosome 12 in a region that contains other potential candidate cytokine genes, including the gene encoding interferon gamma, the prototypical TH1 cytokine with inhibitory activities for TH2 lymphocytes. Taken together, both experimental and genetic studies point to TH2 cytokines, such as IL-4, IL-13, IL-5, and IL-9, as important targets for therapeutic applications in patients with asthma.

Animals↗

Interleukin-9 reduces lung fibrosis and type 2 immune polarization induced by silica particles in a murine model.

We examined the effect of interleukin (IL)-9, a cytokine active on B and T lymphocytes and associated with bronchial asthma, on the development of lung fibrosis induced by crystalline silica particles. Therefore, we compared the response to silica (1 and 5 mg/animal, intratracheally) in transgenic mice that constitutively express high levels of IL-9 (Tg5) and their wild-type counterparts (FVB). At 2 and 4 mo after treatment with silica, histologic examination and measurement of lung hydroxyproline content showed that the severity of fibrosis was significantly less important in Tg5 mice than in their wild-type counterparts. Intraperitoneal injection of IL-9 in C57BL/6 mice also reduced the amplitude of silica-induced lung fibrosis. The reduction of lung fibrosis by IL-9 was associated with a significant expansion of the B-lymphocyte population, both in bronchoalveolar lavage (BAL) and in the pulmonary parenchyma. In wild-type animals, silica-induced fibrosis correlated with markers of a T helper 2-like response such as upregulation of IL-4 levels in lung tissue and an increased immunoglobulin (Ig) G1/IgG2a ratio in BAL. Immunohistochemical studies demonstrated that the upregulation of IL-4 associated with the development of fibrosis was mainly localized in inflammatory alveolar macrophages. In transgenic mice, the level of IL-4 in lung homogenates was not significantly affected by silica treatment, and a reduced IgG1/IgG2a ratio was observed upon treatment with silica. The levels of interferon-gamma were significantly decreased after silica treatment in both strains. Together, these observations point to an antifibrotic effect of IL-9 in pulmonary fibrosis associated with a limitation of the type 2 polarization which accompanies lung fibrosis.

Animals↗

Deleterious effects of IL-9-activated mast cells and neuroprotection by antihistamine drugs in the developing mouse brain.

Elevated mean IL-9 serum levels have been observed in human neonates who will later develop cerebral palsy. In earlier studies, using a newborn mouse model of excitotoxic lesions mimicking those described in human cerebral palsy, we found that IL-9 pretreatment exacerbated brain damage produced by intracerebral injections of the glutamatergic analog ibotenate. Among its different cell targets, the Th2 cytokine IL-9 is a mast cell growth and differentiation factor that can cause mast cells to release various substances including histamine. In the present study, we sought to determine whether the deleterious effects of IL-9 in our mouse model were mediated by mast cells through histamine release. All mouse pups were pretreated with intraperitoneal injections of IL-9 or saline between postnatal days (P) P1 and P5. Immunohistochemistry for murine mast cell protease-1 performed on P5 showed an increased density of labeled cells in the neopallium of IL-9-treated Swiss pups as compared with controls. Western blot analysis confirmed the increased murine mast cell protease-1 brain content of IL-9-treated Swiss mice. IL-9 pretreatment had no significant effect on ibotenate-induced excitotoxic brain lesions in mast cell-deficient P5 pups (WBB6F1/J kit(W/W-v)), whereas IL-9 exacerbated these lesions in the control littermates with normal mast cell populations. Finally, cromoglycate or antihistamine drugs significantly reduced ibotenate-induced brain lesions in IL-9-treated Swiss pups. Taken together, these data suggest that recruitment of cerebral mast cells with histamine release may contribute to the exacerbation of neonatal excitotoxic brain lesions produced by IL-9. Neuroprotective strategies targeting mast cells may be useful in some neonates at risk for cerebral palsy.

Animals↗

Interleukin-9 induces 24P3 lipocalin gene expression in murine T cell lymphomas.

Interleukin-9 (IL-9) is a Th2 cytokine whose overexpression is associated with asthma and T cell lymphomagenesis. All the IL-9 activities studied so far are mediated by a specific hemopoietin receptor that activates a Jak/STAT pathway. Searching for genes specifically modulated by IL-9, we observed that the 24P3 mRNA is strongly upregulated in BW5147 T lymphoma cells upon IL-9 stimulation. 24P3 is a member of the lipocalin family, and has been reported to bind N-formyl-Met-Leu-Phe, a potent neutrophil chemoattractant, and possibly other lipophilic mediators of inflammation. A similar 24P3 induction was observed in other T cell lymphomas (EL4 and TH201) in response to IL-9, as well as in EL4 cells stimulated with IL-6 or IL-1. By contrast, other IL-9-responsive cells such as mast cell line MC9 and B cell lymphoma A20 showed no 24P3 induction upon IL-9 stimulation. Experiments using IL-9R mutants indicated that STAT transcription factors, particularly STAT3, are involved in this process. However, 24P3 gene induction was slow, reaching a plateau from 36 to 72 hours after stimulation and was inhibited if cells were treated with cycloheximide during the first 8 hours of IL-9 stimulation, suggesting an indirect induction requiring new protein synthesis.

Acute-Phase Proteins↗

Interleukin-9 (IL-9) induces cell growth arrest associated with sustained signal transducer and activator of transcription activation in lymphoma cells overexpressing the IL-9 receptor.

Murine interleukin (IL)-9 inhibits apoptosis in murine T lymphomas via signal transducer and activator of transcription (STAT) factors. After transfection of the human IL-9 receptor, human IL-9 had a similar antiapoptotic activity, but, unlike the mouse protein, inhibited proliferation. This effect was correlated with the level of receptor expression and the extent of STAT phosphorylation. Expression of a moderate level of suppressor of cytokine signaling 3 (SOCS3) reduced STAT activation by human IL-9 and prevented inhibition of growth but not of apoptosis. Using mutated IL-9 receptors, we showed that inhibition of proliferation was correlated with STAT1 and STAT3 activation by IL-9 and induction of the cell cycle inhibitor p19/ink4d, a STAT3 target gene. Activation of STAT1 by IFN-gamma did not result in cell growth arrest. In this model, cell growth inhibition is therefore associated with a higher number of receptors, a more robust STAT activation, and a greater sensitivity to SOCS3 expression, compared to apoptosis inhibition.

Animals↗

Role of insulin receptor substrate-2 in interleukin-9-dependent proliferation.

Interleukin-9 (IL-9) stimulation results in JAK, STAT and IRS1/2 phosphorylation. The role of IRS adaptor proteins in IL-9 signaling is not clear. We show that IL-9 induces IRS2 phosphorylation and association with phosphatidylinositol-3 kinase (PI 3-K) p85 subunit in TS1 cells and BaF/9R cells, which proliferate upon IL-9 stimulation. We observed a PI 3-K-dependent phosphorylation of protein kinase B (PKB) in TS1 cells, but not in BaF/9R, nor in other IL-9-dependent cell lines. Finally, 32D cells that were transfected with the IL-9 receptor but lack IRS expression survived in the presence of IL-9. Ectopic IRS1 expression allowed for IL-9-induced proliferation, in the absence of significant PKB phosphorylation.

Animals↗

Human interleukin-10-related T cell-derived inducible factor: molecular cloning and functional characterization as an hepatocyte-stimulating factor.

IL-10-related T cell-derived inducible factor (IL-TIF or IL-21) is a new cytokine structurally related to IL-10 and originally identified in the mouse as a gene induced by IL-9 in T cells and mast cells. Here, we report the cloning of the human IL-TIF cDNA, which shares 79% amino acid identity with mouse IL-TIF and 25% identity with human IL-10. Recombinant human IL-TIF was found to activate signal transducer and activator of transcription factors-1 and -3 in several hepatoma cell lines. IL-TIF stimulation of HepG2 human hepatoma cells up-regulated the production of acute phase reactants such as serum amyloid A, alpha1-antichymotrypsin, and haptoglobin. Although IL-10 and IL-TIF have distinct activities, antibodies directed against the beta chain of the IL-10 receptor blocked the induction of acute phase reactants by IL-TIF, indicating that this chain is a common component of the IL-10 and IL-TIF receptors. Similar acute phase reactant induction was observed in mouse liver upon IL-TIF injection, and IL-TIF expression was found to be rapidly increased after lipopolysaccharide (LPS) injection, suggesting that this cytokine contributes to the inflammatory response in vivo.

Acute-Phase Proteins↗

Cytokine production and killer activity of NK/T-NK cells derived with IL-2, IL-15, or the combination of IL-12 and IL-18.

NK cell populations were derived from murine splenocytes stimulated by IL-2, IL-15, or the combination of IL-12 and IL-18. Whereas NK cells derived with the latter cytokines consisted of an homogeneous population of NK cells (DX5+CD3-), those derived with IL-2 or IL-15 belonged to two different populations, namely NK cells (DX5+CD3-) and T-NK cells (DX5+CD3+). Among NK cells, only those derived with IL-12/IL-18 produced detectable levels of cytokines, namely IFN-gamma, IL-10, and IL-13 (with the exception of IL-13 production by NK cells derived with IL-2). As for T-NK cells, IL-2-stimulated cells produced a wide range of cytokines, including IL-4, IL-5, IL-9, IL-10, and IL-13, but no IFN-gamma, whereas IL-15-derived T-NK cells failed to produce any cytokine. Switch-culture experiments indicated that T-NK cells derived in IL-2 and further stimulated with IL-12/IL-18 produced IFN-gamma and higher IL-13 levels. Next, we observed that NK/T-NK cell populations exerted distinct effects on Ig production by autologous splenocytes according to the cytokines with which they were derived. Thus, addition of NK cells derived in IL-12/IL-18 inhibited Ig production and induced strong cytotoxicity against splenocytes, whereas addition of NK or T-NK cells grown in IL-2 or IL-15 did not. Experiments performed in IFN-gammaR knockout mice demonstrated that IFN-gamma was not involved in the killer activity of IL-12/IL-18-derived NK cells. The hypothesis that their cytotoxic activity was related to the induction of target apoptosis was confirmed on murine A20 lymphoma cells. Experiments performed in MRL/lpr mice indicated that IL-12/IL-18-derived NK cells displayed their distinct killer activity through a Fas-independent pathway. Finally, perforin was much more expressed in IL-12/IL-18-derived NK cells as compared with IL-2- or IL-15-derived NK cells, an observation that might explain their unique cytotoxicity.

Adjuvants, Immunologic↗

STAT5 activation is required for interleukin-9-dependent growth and transformation of lymphoid cells.

Interleukin-9 (IL-9) is a growth factor for T cells and various hematopoietic and lymphoid tumor cells. IL-9 signaling involves activation of Janus kinase (JAK)1 and JAK3 kinases, and signal transducer and activator of transcription (STAT)1, STAT3 and STAT5. Using a dominant negative form of STAT5 (STAT5delta), we demonstrated that this factor is an important mediator of IL-9-dependent Ba/F3 cell growth. Mutation of the STAT binding site of the IL-9 receptor (tyr116phe) results in an important decrease in STAT activation and inhibition of proliferation in the presence of IL-9. A small number of cells escape this inhibition, and IL-9-dependent cell lines could be derived. The selected cells required activation of STAT5 for growth, which was blocked by STAT5delta expression and enhanced by overexpression of wild-type STAT5. In contrast to parental cells, Ba/F3-Phe116 cells growing in the presence of IL-9 further progress to cytokine-independent tumorigenic clones. These tumorigenic clones exhibited a strong cytokine-independent activation of JAK1 and STAT5, which most likely supports their proliferation. Transfection of a constitutively activated variant of STAT5 promoted the growth of wild-type Ba/F3 cells in the absence of cytokine. Finally, the expression of the proto-oncogene pim-1 was correlated with STAT5 activation and cell growth. Our data suggest that STAT5 is an important mediator of IL-9-driven proliferation and that dysregulation of STAT5 activation favors tumorigenesis of lymphoid cells.

Animals↗

IL-9 protects mice from Gram-negative bacterial shock: suppression of TNF-alpha, IL-12, and IFN-gamma, and induction of IL-10.

IL-9 is a T cell-derived cytokine that, similar to the Th2 cytokines IL-4 and IL-10, has been implicated in the response to parasitic infections, allergy, and inflammatory processes. Because both IL-4 and IL-10 can confer protection to mice from septic shock, we investigated whether IL-9 may also be capable of conferring resistance on recipients of an otherwise lethal challenge with Pseudomonas aeruginosa. Prophylactic injections of rIL-9 appeared to be most effective in preventing the onset of a lethal shock, according to a pattern that was both dose dependent and time dependent. The protective effect of IL-9 was correlated with marked decreases in the production of the inflammatory mediators TNF-alpha, IL-12, and IFN-gamma, as well as the induction of the anti-inflammatory cytokine IL-10. Sustained levels of IL-9-specific transcripts could be detected in the spleens of mice recovering from sublethal P. aeruginosa infection. Therefore, IL-9 may be protective in septic shock via a rather unique mechanism involving a complex modulation of inflammatory and anti-inflammatory mediators.

Adjuvants, Immunologic↗

Signals from the IL-9 receptor are critical for the early stages of human intrathymic T cell development.

Highly purified human CD34+ hemopoietic precursor cells differentiate into mature T cells when seeded in vitro in isolated fetal thymic lobes of SCID mice followed by fetal thymus organ culture (FTOC). Here, this chimeric human-mouse FTOC was used to address the role of IL-9 and of the alpha-chain of the IL-9 receptor (IL-9Ralpha) in early human T cell development. We report that addition of the mAb AH9R7, which recognizes and blocks selectively the human high affinity alpha-chain of the IL-9R, results in a profound reduction of the number of human thymocytes. Analysis of lymphoid subpopulations indicates that a highly reduced number of cells undergo maturation from CD34+ precursor cells toward CD4+CD3-CD8-CD1+ progenitor cells and subsequently toward CD4+CD8+ double positive (DP) thymocytes. Addition of IL-9 to the FTOC resulted in an increase in cell number, without disturbing the frequencies of the different subsets. These data suggest that IL-9Ralpha signaling is critical in early T lymphoid development.

Adjuvants, Immunologic↗

Cloning and characterization of IL-10-related T cell-derived inducible factor (IL-TIF), a novel cytokine structurally related to IL-10 and inducible by IL-9.

IL-9 is a Th2 cytokine active on various cell types such as T and B lymphocytes, mast cells, and eosinophils, and potentially involved in allergy and asthma. To understand better the molecular mechanisms underlying the activity of this cytokine, we used a cDNA subtraction method to identify genes specifically induced by IL-9 in mouse T cells. One of the IL-9-regulated genes isolated by this approach turned out to encode a 180-amino acid long protein, including a potential signal peptide, and showing 22% amino acid identity with IL-10. This protein, designated IL-10-related T cell-derived inducible factor (IL-TIF), is induced by IL-9 in thymic lymphomas, T cells, and mast cells, and by lectins in freshly isolated splenocytes. Experiments concerning the mechanism regulating IL-TIF expression in T cells indicate that IL-9 induction is rapid (within 1 h), does not require protein synthesis, and depends on the activation of the Janus kinase (JAK)-STAT pathway. In vivo, constitutive expression of IL-TIF was detected by RT-PCR in thymus and brain, suggesting that the role of this new factor is not restricted to the immune system. Transfection of HEK293 cells with the IL-TIF cDNA resulted in the production of a glycosylated protein of about 25 kDa that was found to induce STAT activation in mesangial and neuronal cell lines. Further studies will have to address the possibility that some of the IL-9 activities may be mediated by IL-TIF.

Amino Acid Sequence↗

Anti-IL-9 vaccination prevents worm expulsion and blood eosinophilia in Trichuris muris-infected mice.

Production of neutralizing anti-IL-9 antibodies was induced in mice by immunization with mouse IL-9 coupled to ovalbumin. In the six mouse strains tested, a strong and long-lasting anti-IL-9 response developed with seric inhibitory titers of 10(-3) to 10(-5), as measured in an in vitro IL-9-dependent cell proliferation assay. In vivo, this immunization completely abrogated the increase in mast-cell protease-1 levels as well as the eosinophilia observed in mice after implantation of an IL-9-secreting tumor. We took advantage of this method to assess the role of IL-9 in infections with nematode Trichuris muris, where IL-9 production correlates with the resistant phenotype. C57BL/6 mice, which normally expel the parasite, became susceptible after anti-IL-9 immunization, demonstrating that IL-9 plays a critical role in this model. In addition, neutralization of IL-9 also inhibited parasite-induced blood eosinophilia. Taken together, the present data demonstrate the potency of our strategy to antagonize IL-9 in vivo and shows that this cytokine plays a major role in resistance against T. muris infection.

Animals↗

Interleukin-10 blockade corrects impaired in vitro cellular immune responses of systemic lupus erythematosus patients.

OBJECTIVE: Many systemic lupus erythematosus (SLE) patients display impaired cellular immune responses against allo- or recall antigens. Given the down-regulating properties of interleukin-10 (IL-10) on antigen-presenting cell functions, this study was undertaken to investigate whether the well-known overproduction of IL-10 by SLE peripheral blood mononuclear cells (PBMC) was involved in this process. METHODS: We measured the proliferation of SLE or control PBMC against irradiated allogeneic dendritic cells in the absence or presence of antibodies blocking IL-10 activity, or in the absence or presence of IL-12. RESULTS: As a group, SLE PBMC proliferated against allogeneic targets less than control PBMC. However, SLE patients could be categorized as good responders or poor responders according to the amplitude of their allogeneic response. Interestingly, serum IL-10 concentrations were significantly higher in the poor responders than in the good responders or in the controls, and addition of antibodies blocking IL-10 activity significantly increased the proliferative responses of the group. We confirmed the role of IL-10 in the impaired allogeneic responses displayed by SLE PBMC by demonstrating that addition of IL-10-containing SLE PBMC supernatants inhibited a normal allogeneic response between unrelated healthy controls, and by showing that this inhibitory effect was commensurate with the concentrations of IL-10 measured in the supernatants. In this experimental setting, we also demonstrated that IL-10-containing SLE PBMC supernatants inhibited IL-12 p35 and IL-12 p40 gene expression. Consistent with the last observation, we found that addition of exogenous IL-12 restored the proliferation of poor-responder SLE patients' PBMC. CONCLUSION: Taken together, these results indicate that dysregulation of the IL-10/IL-12 balance plays a critical role in the impaired cellular immune responses observed in SLE patients.

Adolescent↗

An animal model for anaplastic large cell lymphoma in the immunocompetent syngeneic C57Bl/6 mouse.

We report on the analysis of a murine anaplastic lymphoid cell line TS1G6, established recently by interleukin (IL)-9 transfection. TS1G6 revealed a highly characteristic pattern of large anaplastic cells with mononuclear, binuclear, or multinuclear cells resembling Hodgkin (H) or Sternberg-Reed (SR) cells. This cell line is tumorigenous after injection of as few as 10(4) lymphoma cells into nude or immunocompetent C57Bl/6 mice and leads to death from progressive disease of all treated animals within a few weeks. The histological analysis of these tumors revealed a diffuse large cell malignant lymphoma that is morphologically almost identical to human anaplastic large cell lymphoma (ALCL). The lymphoma cells did not show overexpression of the anaplastic lymphoma kinase (ALK) gene, which is found in about 50% of the cases of human ALCL. Thus, this model may be an animal model for an important subset of human ALCL. The cytokine profile, which is of the T helper 2 type, showed strong parallels to the human lymphoma counterpart. Mice suffering from such lymphomas could not be cured with a regimen using high dose cyclophosphamide similar to many ALCL patients. Such an animal model for ALCL has not yet been recognized, but may provide the basis for investigating new antitumor immunotherapies in a fully immunocompetent host.

Anaplastic Lymphoma Kinase↗