transforming-growth-factor-beta and Anemia

Myelodysplastic syndromes (MDS) are acquired bone marrow malignant disorders characterized by ineffective hematopoiesis, resulting from a complex interaction between genetic and epigenetic mutations, alterations of the marrow microenvironment, and the immune system. In 2001, the World Health Organization (WHO) proposed a classification that integrates morphologic and genetic information, considering the MDS with ring sideroblasts (MDS-RS) as a distinct entity. Considering the strong association between MDS-RS and SF3B1 mutation and its importance in the development of MDS, the last WHO classification replaced the prior entity of MDS-RS with MDS with SF3B1 mutation. Several studies were performed to explore this genotype-phenotype correlation. Mutant SF3B1 protein deregulates the expression of genes implicated in developing hematopoietic stem and progenitor cells. Of paramount importance are PPOX and ABCB7 involved in iron metabolism. Another essential role in hemopoiesis is played by the transforming growth factor-beta (TGF-β) receptor. This gene exerts its effects on SMAD pathways, regulating hematopoiesis through effects on balancing proliferation and apoptosis cell inactivity, differentiation, and migration. Luspatercept (ACE-536) is a soluble fusion protein that inhibits molecules in the TGF-β superfamily. Since its structure resembles the TGF-β family receptor, it catches TGF-β superfamily ligands before binding to the receptor, resulting in reduced activation of SMAD signaling, thus enabling erythroid maturation. Luspatercept was investigated in the phase III trial MEDALIST, showing promising efficacy in treating anemia compared to placebo. Nowadays, further studies are needed to explore the real potential of luspatercept, investigating the biological features likely associated with treatment response, the potential use in combination treatments, and its role in the treatment of naïve MDS.

Topics: Anemia; Bone Marrow; Flavoproteins; Humans; Mitochondrial Proteins; Mutation; Myelodysplastic Syndromes; Phosphoproteins; Protoporphyrinogen Oxidase; RNA Splicing Factors; Transforming Growth Factor beta

Sotatercept (ACE-011) is an activin receptor IIA-Fc (ActRIIA-Fc) fusion protein currently under investigation for its potential in the treatment of hematologic diseases. By impeding the activities of the overexpressed growth and differentiation factor 11 (GDF11), activin A, and other members of the transforming growth factor-β (TGF-β) superfamily, commonly found in hematologic disorders, sotatercept aims to restore the normal functioning of red blood cell maturation and osteoblast differentiation. This action is anticipated to enhance anemia management and hinder the progression of myeloma. Simultaneously, comprehensive research is ongoing to investigate sotatercept's pharmacokinetics and potential adverse reactions, thus laying a robust foundation for its prospective clinical use. In this review, we provide a detailed overview of TGF-β pathways in physiological and hematologic disorder contexts, outline the potential mechanism of sotatercept, and delve into its pharmacokinetics and clinical research advancements in various hematologic diseases. A particular emphasis is given to the relationship between sotatercept dosage and its efficacy or associated adverse reactions.

Topics: Activins; Anemia; Bone Morphogenetic Proteins; Erythropoiesis; Growth Differentiation Factors; Humans; Prospective Studies; Recombinant Fusion Proteins; Transforming Growth Factor beta

Anemia is the most common clinical manifestation of myelodysplastic syndrome (MDS), and most patients become red blood cell transfusion dependent. Defective erythropoiesis includes impaired terminal erythroid maturation. There are limited options for treatments of anemia in lower-risk MDS after failure of erythroid-stimulating agents. Luspatercept is an activin receptor type IIB fusion ligand trap novel agent. Luspatercept showed promising activity for treating anemia in patients with MDS with ring sideroblast subtypes. This article reviews the mechanism of impaired erythropoiesis in MDS. It summarizes clinical data with luspatercept and foresees how to best use this treatment in practice.

Topics: Activin Receptors, Type II; Anemia; Clinical Trials as Topic; Erythropoiesis; Humans; Immunoglobulin Fc Fragments; Myelodysplastic Syndromes; Recombinant Fusion Proteins; Signal Transduction; Transforming Growth Factor beta

Myelodysplastic syndromes (MDS) encompass a clinically heterogenous group of diseases defined by a clonal bone marrow failure state. Patients with lower-risk MDS primarily suffer from the consequences of anemia, with a subset having increased risks of bleeding and infection. There are few good therapeutic options for this patient population, as patients are dependent on cytokine support to improve hematopoiesis. Our review will discuss luspatercept, a transforming growth factor (TGF)-Beta ligand trap, the first new Food & Drug Administration (FDA)-approved treatment in MDS in over a decade. We will explore the different TGF-Beta ligand traps that have been developed for a number of diseases, with a focus on myeloid malignancies.

Topics: Activin Receptors, Type II; Anemia; Animals; Hematinics; Humans; Immunoglobulin Fc Fragments; Myelodysplastic Syndromes; Recombinant Fusion Proteins; Transforming Growth Factor beta

Sotatercept and luspatercept are recombinant soluble activin type-II receptor-IgG-Fc fusion proteins that are tested in clinical trials for the treatment of various types of anemias, including renal anemia. The mechanism of the action of the novel drugs is incompletely understood, but it seems to be based on the inactivation of soluble proteins of the transforming growth factor-ß (TGFß) family. This review considers pros and cons of the clinical use of the drugs in reference to the current therapy with recombinant erythropoiesis-stimulating agents (ESAs).. One or more activin type-II receptor (ActRII) ligands appear to inhibit erythroid precursors, for example growth and differentiation factor 11. Trapping of these ligands by the recombinant ActRII fusion proteins, sotatercept and luspatercept increases red blood cell numbers and hemoglobin levels in humans. Reportedly, the novel compounds were well tolerated in trials on healthy volunteers and patients suffering from anemia due to chronic kidney disease or malignancies. On approval, the drugs may prove particularly useful in patients suffering from ineffective erythropoiesis, such as in myelodysplastic syndrome, multiple myeloma or ß-thalassemia, where ESAs are of little use. Independent of their effect on erythropoiesis, ActRII ligand traps were found to exert beneficial effects on renal tissue in experimental animals.. ESAs are likely to remain standard of care in renal anemia. There is a need for a better understanding of the effects of ActRII ligand traps on TGFß-like proteins. The novel drugs have not been approved for sale as therapeutics so far. Their long-term efficacy and safety still needs to be proven, particularly with respect to immunogenicity. Antifibrotic effects may be worthy to be investigated in humans.

Topics: Activin Receptors; Activin Receptors, Type II; Activins; Anemia; Animals; Erythropoiesis; Hematinics; Humans; Immunoglobulin Fc Fragments; Ligands; Recombinant Fusion Proteins; Renal Insufficiency, Chronic; Transforming Growth Factor beta

β-thalassemia, a hereditary blood disorder caused by defective synthesis of hemoglobin β globin chains, leads to ineffective erythropoiesis and chronic anemia that may require blood transfusions. Sotatercept (ACE-011) acts as a ligand trap to inhibit negative regulators of late-stage erythropoiesis in the transforming growth factor β superfamily, correcting ineffective erythropoiesis. In this phase II, open-label, dose-finding study, 16 patients with transfusion-dependent β -thalassemia and 30 patients with non-transfusion-dependent β-thalassemia were enrolled at seven centers in four countries between November 2012 and November 2014. Patients were treated with sotatercept at doses of 0.1, 0.3, 0.5, 0.75, or 1.0 mg/kg to determine a safe and effective dose. Doses were administered by subcutaneous injection every 3 weeks. Patients were treated for ≤22 months. Response was assessed as a ≥20% reduction in transfusion burden sustained for 24 weeks in transfusion-dependent β-thalassemia patients, and an increase in hemoglobin level of ≥1.0 g/dL sustained for 12 weeks in non-transfusion-dependent β-thalassemia patients. Sotatercept was well tolerated. After a median treatment duration of 14.4 months (range 0.6-35.9), no severe life-threatening adverse events were observed. Thirteen percent of patients reported serious but manageable adverse events. The active dose of sotatercept was ≥0.3 mg/kg for patients with non-transfusion-dependent β-thalassemia and ≥0.5 mg/kg for those with transfusion-dependent β-thalassemia. Of 30 non-transfusion-dependent β-thalassemia patients treated with ≥0.1 mg/kg sotatercept, 18 (60%) achieved a mean hemoglobin increase ≥1.0 g/dL, and 11 (37%) an increase ≥1.5 g/dL, sustained for ≥12 weeks. Four (100%) transfusion-dependent β-thalassemia patients treated with 1.0 mg/kg sotatercept achieved a transfusion-burden reduction of ≥20%. Sotatercept was effective and well tolerated in patients with β-thalassemia. Most patients with non-transfusion-dependent β-thalassemia treated with higher doses achieved sustained increases in hemoglobin level. Transfusion-dependent β-thalassemia patients treated with higher doses of sotatercept achieved notable reductions in transfusion requirements. This trial was registered at ClinicalTrials.gov with the number NCT01571635.

Topics: Adult; Anemia; beta-Thalassemia; Biomarkers; Blood Transfusion; Combined Modality Therapy; Erythrocyte Indices; Erythropoiesis; Female; Hemoglobins; Humans; Ligands; Male; Middle Aged; Recombinant Fusion Proteins; Transforming Growth Factor beta; Treatment Outcome

Purpose Interleukin-10 (IL-10) stimulates the expansion and cytotoxicity of tumor-infiltrating CD8+ T cells and inhibits inflammatory CD4+ T cells. Pegylation prolongs the serum concentration of IL-10 without changing the immunologic profile. This phase I study sought to determine the safety and antitumor activity of AM0010. Patients and Methods Patients with selected advanced solid tumors were treated with AM0010 in a dose-escalation study, which was followed by a renal cell cancer (RCC) dose-expansion cohort. AM0010 was self-administered subcutaneously at doses of 1 to 40 μg/kg once per day. Primary end points were safety and tolerability; clinical activity and immune activation were secondary end points. Results In the dose-escalation and -expansion cohorts, 33 and 18 patients, respectively, were treated with daily subcutaneous injection of AM0010. AM0010 was tolerated in a heavily pretreated patient population. Treatment-related adverse events (AEs) included anemia, fatigue, thrombocytopenia, fever, and injection site reactions. Grade 3 to 4 nonhematopoietic treatment-related AEs, including rash (n = 2) and transaminitis (n = 1), were observed in five of 33 patients. Grade 3 to 4 anemia or thrombocytopenia was observed in five patients. Most treatment-related AEs were transient or reversible. AM0010 led to systemic immune activation with elevated immune-stimulatory cytokines and reduced transforming growth factor beta in the serum. Partial responses were observed in one patient with uveal melanoma and four of 15 evaluable patients with RCC treated at 20 μg/kg (overall response rate, 27%). Prolonged stable disease of at least 4 months was observed in four patients, including one with colorectal cancer with disease stabilization for 20 months. Conclusion AM0010 has an acceptable toxicity profile with early evidence of antitumor activity, particularly in RCC. These data support the further evaluation of AM0010 both alone and in combination with other immune therapies and chemotherapies.

Topics: Adult; Aged; Aged, 80 and over; Anemia; Carcinoma, Renal Cell; Cytokines; Drug Eruptions; Exanthema; Fatigue; Female; Fever; Humans; Injections, Subcutaneous; Interferon-gamma; Interleukin-10; Interleukin-4; Interleukin-8; Kidney Neoplasms; Male; Melanoma; Middle Aged; Neoplasms; Polyethylene Glycols; Recombinant Proteins; Thrombocytopenia; Transforming Growth Factor beta; Uveal Neoplasms; Young Adult

To investigate the safety and efficacy of the combination of lenalidomide and prednisone in patients with myelofibrosis (MF).. Forty patients with MF were treated. Therapy consisted of lenalidomide 10 mg/d (5 mg/d if baseline platelet count < 100 x 10(9)/L) on days 1 through 21 of a 28-day cycle for six cycles, in combination with prednisone 30 mg/d orally during cycle 1, 15 mg/d during cycle 2, and 15 mg/d every other day during cycle 3. Lenalidomide therapy was continued indefinitely in patients exhibiting clinical benefit.. The median follow-up was 22 months (range, 6 to 27). Responses were recorded in 12 patients (30%) and are ongoing in 10 (25%). The median time to response was 12 weeks (range, 2 to 32). According to the International Working Group for Myelofibrosis Research and Treatment consensus criteria, three patients (7.5%) had partial response and nine patients (22.5%) had clinical improvement durable for a median of 18 months (range, 3.5 to 24+). Overall response rates were 30% for anemia and 42% for splenomegaly. Moreover, 10 of 11 assessable responders who started therapy with reticulin fibrosis grade 4 experienced reductions to at least a score of 2. All eight JAK2(V617F)-positive responders experienced a reduction of the baseline mutant allele burden, which was greater than 50% in four, including one of whom the mutation became undetectable. Grade 3 to 4 hematologic adverse events included neutropenia (58%), anemia (42%), and thrombocytopenia (13%).. The combination of lenalidomide and prednisone induces durable clinical, molecular, and pathologic responses in MF.

Topics: Adult; Aged; Aged, 80 and over; Anemia; Antineoplastic Agents; Drug Therapy, Combination; Enzyme-Linked Immunosorbent Assay; Female; Fibroblast Growth Factor 2; Glucocorticoids; Humans; Janus Kinase 2; Lenalidomide; Male; Middle Aged; Mutation; Neutropenia; Platelet-Derived Growth Factor; Prednisone; Primary Myelofibrosis; Thalidomide; Thrombocytopenia; Transforming Growth Factor beta; Treatment Outcome

Short-term effects of recombinant human erythropoietin on serum levels of transforming growth factor beta-1, interleukin 1-alpha, interleukin 3, interferon gamma, and tumour necrosis factor alpha in patients with chronic renal failure on chronic haemodialysis were investigated. Recombinant human erythropoietin was applied subcutaneously in a dose of 75 IU/kg on 19 patients. Serum levels of transforming growth factor beta-1, interleukin 1-alpha, interleukin 3, interferon gamma, tumour necrosis factor alpha and erythropoietin, red blood cell parameters: red blood cell count, haemoglobin, haematocrit, and erythrocyte indices were determined before and after recombinant human erythropoietin single application. Transforming growth factor beta-1 serum levels were decreased after recombinant human erythropoietin (22.70 +/- 1.51 ng/ml versus 18.77 +/- 1.70 ng/ml (p < 0.01). None of the other investigated parameters was influenced significantly by recombinant human erythropoietin. Recombinant human erythropoietin in patients with chronic renal failure on chronic haemodialysis may influence anaemia not only through its stimulating effect on erythropoiesis, but also by direct oxygen-independent decrease of at least one of the negative regulators of erythropoiesis--the transforming growth factor beta.

Topics: Adult; Anemia; Erythropoietin; Female; Humans; Interferon-gamma; Interleukin-1; Interleukin-3; Kidney Failure, Chronic; Male; Recombinant Proteins; Renal Dialysis; Transforming Growth Factor beta; Tumor Necrosis Factor-alpha

Cancer cachexia is a wasting syndrome that is quite common in terminal-stage cancer patients. Cancer-related anemia is one of the main features of cancer cachexia and mostly results in a poor prognosis. The disadvantages of the current therapies are obvious, but few new treatments have been developed because the pathological mechanism remains unclear.. C57BL/6 mice were subcutaneously injected with Lewis lung carcinoma cells to generate a cancer-related anemia model. The treated group received daily intraperitoneal injections of SB505124. Blood parameters were determined with a routine blood counting analyzer. Erythroid cells and hematopoietic stem/progenitor cells were analyzed by flow cytometry. The microarchitecture changes of the femurs were determined by micro-computed tomography scans. Smad2/3 phosphorylation was analyzed by immunofluorescence and Western blotting. The changes in the hematopoietic stem cell niche were revealed by qPCR analysis of both fibrosis-related genes and hematopoietic genes, fibroblastic colony-forming unit assays, and lineage differentiation of mesenchymal stromal cells.. The mouse model exhibited hematopoietic suppression, marked by a decrease of erythrocytes in the peripheral blood, as well as an increase of immature erythroblasts and reduced differentiation of multipotent progenitors in the bone marrow. The ratio of bone volume/total volume, trabecular number, and cortical wall thickness all appeared to decrease, and the increased osteoclast number has led to the release of latent TGFβ and TGFβ signaling over-activation. Excessive TGFβ deteriorated the hematopoietic stem cell niche, inducing fibrosis of the bone marrow as well as the transition of mesenchymal stromal cells. Treatment with SB505124, a small-molecule inhibitor of TGFβ signaling, significantly attenuated the symptoms of cancer-related anemia in this model, as evidenced by the increase of erythrocytes in the peripheral blood and the normalized proportion of erythroblast cell clusters. Meanwhile, hindered hematopoiesis and deteriorated hematopoietic stem cell niche were also shown to be restored with SB505124 treatment.. This study investigated the role of TGFβ released by bone remodeling in the progression of cancer-related anemia and revealed a potential therapeutic approach for relieving defects in hematopoiesis.

Topics: Anemia; Animals; Cell Differentiation; Hematopoiesis; Hematopoietic Stem Cells; Humans; Mice; Mice, Inbred C57BL; Neoplasms; Stem Cell Niche; Transforming Growth Factor beta; X-Ray Microtomography

In end-stage renal disease (ESRD) patients receiving dialysis, anemia is common and related to a higher mortality rate. Erythropoietin (EPO) resistance and iron refractory anemia require red blood cell transfusions. Myelodysplastic syndrome (MDS) is a disease with hematopoietic dysplasia. There are limited reports regarding ESRD patients with MDS. We aim to assess whether, for ESRD patients, undergoing dialysis is a predictive factor of MDS by analyzing data from the Taiwan National Health Insurance Research Database. We enrolled 74,712 patients with chronic renal failure (ESRD) who underwent dialysis and matched 74,712 control patients. In our study, we noticed that compared with the non-ESRD controls, in ESRD patients, undergoing dialysis (subdistribution hazard ratio [sHR] = 1.60, 1.16-2.19) and age (sHR = 1.03, 1.02-1.04) had positive predictive value for MDS occurrence. Moreover, more units of red blood cell transfusion (higher than 4 units per month) was also associated with a higher incidence of MDS. The MDS cumulative incidence increased with the duration of dialysis in ESRD patients. These effects may be related to exposure to certain cytokines, including interleukin-1, tumor necrosis factor-α, and tumor growth factor-β. In conclusion, we report the novel finding that ESRD patients undergoing dialysis have an increased risk of MDS.

Topics: Adult; Aged; Anemia; Erythrocyte Transfusion; Erythropoietin; Female; Humans; Interleukin-1; Iron; Kidney Failure, Chronic; Male; Middle Aged; Myelodysplastic Syndromes; Proportional Hazards Models; Renal Dialysis; Renal Insufficiency, Chronic; Transforming Growth Factor beta; Tumor Necrosis Factor-alpha

Burst-forming unit erythroid progenitors (BFU-Es) are so named based on their ability to generate in methylcellulose culture large colonies of erythroid cells that consist of "bursts" of smaller erythroid colonies derived from the later colony-forming unit erythroid progenitor erythropoietin (Epo)-dependent progenitors. "Early" BFU-E cells forming large BFU-E colonies presumably have higher capacities for self-renewal than do "late" BFU-Es forming small colonies, but the mechanism underlying this heterogeneity remains unknown. We show that the type III transforming growth factor β (TGF-β) receptor (TβRIII) is a marker that distinguishes early and late BFU-Es. Transient elevation of TβRIII expression promotes TGF-β signaling during the early BFU-E to late BFU-E transition. Blocking TGF-β signaling using a receptor kinase inhibitor increases early BFU-E cell self-renewal and total erythroblast production, suggesting the usefulness of this type of drug in treating Epo-unresponsive anemias.

Topics: Anemia; Animals; Antigens, Differentiation; Erythrocytes; Erythroid Precursor Cells; Erythropoietin; Humans; Mice; Proteoglycans; Receptors, Transforming Growth Factor beta; Signal Transduction; Transforming Growth Factor beta

Even though myelodysplastic syndromes (MDS) are characterized by ineffective hematopoiesis, the molecular alterations that lead to marrow failure have not been well elucidated. We have previously shown that the myelosuppressive TGF-β pathway is constitutively activated in MDS progenitors. Because there is conflicting data about upregulation of extracellular TGF-β levels in MDS, we wanted to determine the molecular basis of TGF-β pathway overactivation and consequent hematopoietic suppression in this disease. We observed that SMAD7, a negative regulator of TGF-β receptor I (TBRI) kinase, is markedly decreased in a large meta-analysis of gene expression studies from MDS marrow-derived CD34(+) cells. SMAD7 protein was also found to be significantly decreased in MDS marrow progenitors when examined immunohistochemically in a bone marrow tissue microarray. Reduced expression of SMAD7 in hematopoietic cells led to increased TGF-β-mediated gene transcription and enhanced sensitivity to TGF-β-mediated suppressive effects. The increased TGF-β signaling due to SMAD7 reduction could be effectively inhibited by a novel clinically relevant TBRI (ALK5 kinase) inhibitor, LY-2157299. LY-2157299 could inhibit TGF-β-mediated SMAD2 activation and hematopoietic suppression in primary hematopoietic stem cells. Furthermore, in vivo administration of LY-2157299 ameliorated anemia in a TGF-β overexpressing transgenic mouse model of bone marrow failure. Most importantly, treatment with LY-2157199 stimulated hematopoiesis from primary MDS bone marrow specimens. These studies demonstrate that reduction in SMAD7 is a novel molecular alteration in MDS that leads to ineffective hematopoiesis by activating of TGF-β signaling in hematopoietic cells. These studies also illustrate the therapeutic potential of TBRI inhibitors in MDS.

Topics: Anemia; Hematopoiesis; Hematopoietic Stem Cells; Humans; K562 Cells; Myelodysplastic Syndromes; Protein Kinase Inhibitors; Protein Serine-Threonine Kinases; Pyrazoles; Quinolines; Receptor, Transforming Growth Factor-beta Type I; Receptors, Transforming Growth Factor beta; Signal Transduction; Smad7 Protein; Transforming Growth Factor beta

Pachydermoperiostosis (PDP) is a rare disorder of bone and connective tissue growth. A 21-year-old man was referred to our hospital with anemia. He showed characteristics of PDP. Bone marrow biopsy showed myelofibrosis. Chromosomal abnormalities or JAK2 mutation were not found. Anemia gradually progressed, and he became transfusion-dependent. Oral prednisolone was initiated; it gradually improved his anemia and rendered the patient free of transfusion. However, other clinical symptoms such as clubbed fingers and skin hypertrophy remained unimproved. In this case, the serum concentration of vascular endothelial growth factor and transforming growth factor-β levels were increased. Further investigation will be necessary to establish appropriate treatment strategies for this disease.

Topics: Anemia; Bone Marrow; DNA Mutational Analysis; Humans; Janus Kinase 2; Male; Osteoarthropathy, Primary Hypertrophic; Osteoarthropathy, Secondary Hypertrophic; Prednisolone; Primary Myelofibrosis; Transforming Growth Factor beta; Vascular Endothelial Growth Factor A; Young Adult

Erythropoiesis-stimulating agents (ESAs) may have therapeutic benefits beyond ameliorating anemia. Although ESAs have renoprotective effects in acute/chronic renal injury models, their effects on blood pressure could also worsen chronic renal failure (CRF). The development of human cell-derived erythropoietin analogue epoetin delta prompted us (1) to investigate whether in a 5/6th nephrectomy-induced CRF rat model, epoetin delta-mediated renoprotective effects occur independently of its hematopoietic effects and (2) to unravel the involvement of particular factors herein.. After induction of CRF in Wistar rats, epoetin delta was administered for 8 weeks at different doses: 0 IU/kg (uremic control); 48, 100 or 300 IU/kg 1x/week, and 16 or 100 IU/kg 3x/week. During this period hematopoietic and renal functional parameters as well as systolic blood pressure (SBP) were monitored.. After 8 weeks, control CRF rats showed reduced hematocrit (Hct)/hemoglobin (Hb) levels and increased SBP. Epoetin delta dose-dependently attenuated the reduction in Hct/Hb. Furthermore, epoetin delta treatment resulted in reduced deterioration of renal function in CRF rats after 8 weeks which was accompanied by decreased collagen deposition, renal fibrosis and interstitial macrophage infiltration. Remarkably, these renoprotective effects did not show the same dose dependency as compared to that seen for the hematopoietic response and were also seen at subhematopoietic doses. Interestingly, epoetin delta treatment resulted in a dose-dependent decrease of profibrotic (TGF-beta) and proapoptotic (Bcl-2-associated X protein) genes together with a significant dose-dependent increase of antifibrotic (hepatocyte growth factor) and antiapoptotic (Bcl-2) genes. Epoetin delta treatment had no effect on VEGF expression.. Epoetin delta treatment could delay the progression of CRF through antiapoptotic and antifibrotic mechanisms. This protective action of epoetin delta on the kidney probably is not directly related to its hematopoietic effects.

Topics: Anemia; Animals; Apoptosis; bcl-2-Associated X Protein; Blood Pressure; Disease Models, Animal; Disease Progression; Erythropoietin; Fibrosis; Hematinics; Hepatocyte Growth Factor; Humans; Kidney; Kidney Failure, Chronic; Male; Nephrectomy; Rats; Rats, Wistar; Recombinant Proteins; Transforming Growth Factor beta

The hematopoietic hormone erythropoietin (Epo), regularly produced by the kidneys and the liver, is also expressed in neuronal tissue, where it has been found to mediate paracrine neuroprotective effects. In most studies exploring the rescue effects of Epo, apoptosis was exogenously induced by different cell death stimuli. Herein, we set out to study the expression and function of Epo in physiologically occurring apoptosis in a model of retinal development. We made use of an organotypic retinal wholemount culture system that resembles the physiological in vivo situation with cell connections still retained. Epo mRNA expression in the retina, liver, and kidney showed a significant increase during early development, coinciding with the anemia of the newborn. In the retina of Epo-green fluorescent protein transgenic mice, Epo-expressing cells were identified and found to be distributed in the retinal ganglion cell layer. Treatment of retinal wholemount cultures with recombinant Epo resulted in a significant decrease of apoptotic ganglion cells as well as photoreceptor cells throughout retinal development. Moreover, transforming growth factor-beta-induced apoptosis was completely antagonized by Epo when both factors were simultaneously applied. Investigations on the signaling pathway revealed a decrease in Bax mRNA levels in Epo-treated retinal cells. We conclude that Epo exerts wide and prolonged neuroprotective activity in physiologically occurring apoptosis and thus contributes to proper retinal development.

Topics: Anemia; Animals; Animals, Newborn; Apoptosis; bcl-2-Associated X Protein; Erythropoietin; Humans; Mice; Mice, Inbred C57BL; Mice, Transgenic; Neurons; Photoreceptor Cells; Recombinant Proteins; Retina; Retinal Ganglion Cells; RNA, Messenger; Signal Transduction; Specific Pathogen-Free Organisms; Transforming Growth Factor beta

The socioeconomic implications of trypanosomosis in sub-Saharan Africa and the limitations of its current control regimes have stimulated research into alternative control methods. Considering the pro- and anti-inflammatory properties of transforming growth factor beta1 (TGF-beta1) and its potential to enhance immunity against protozoan parasites, we examined the effects of intraperitoneally delivered TGF-beta1 in C57BL/6 mice infected with Trypanosoma congolense, the hemoprotozoan parasite causing nagana in cattle. A triple dose of 10 ng TGF-beta1 significantly reduced the first parasitemic peak and delayed mortality of infected mice. Furthermore, exogenous TGF-beta1 significantly decreased the development of trypanosome-induced anemia and splenomegaly. The apparent TGF-beta1-induced antitrypanosome protection, occurring mainly during the early stage of infection, correlated with an enhanced parasite antigen-specific Th1 cell response characterized by a skewed type I cytokine response and a concomitant stronger antitrypanosome immunoglobulin G2a antibody response. Infected TGF-beta1-pretreated mice exhibited a significant reduction in the trypanosome-induced hyperexpansion of B cells. Furthermore, evidence is provided herein that exogenous TGF-beta1 activates macrophages that may contribute to parasite control. Collectively, these data indicate that exogenous TGF-beta1 is immunostimulative, inducing partial protection against T. congolense infection, possibly through mechanisms involving innate immune responses.

Topics: Anemia; Animals; Antibodies, Protozoan; B-Lymphocytes; Cytokines; Disease Models, Animal; Female; Immunoglobulin G; Immunologic Factors; Macrophage Activation; Mice; Mice, Inbred C57BL; Parasitemia; Splenomegaly; Th1 Cells; Transforming Growth Factor beta; Trypanosoma congolense; Trypanosomiasis, African

The tumor suppressor Smad4 mediates signaling by the transforming growth factor beta (TGF-beta) superfamily of ligands. Previous studies showed that several TGF-beta family members exert important functions in hematopoiesis. Here, we studied the role of Smad4 in adult murine hematopoiesis using the inducible Mx-Cre/loxP system. Mice with homozygous Smad4 deletion (Smad4(Delta/Delta)) developed severe anemia 6 to 8 weeks after induction (mean hemoglobin level 70 g/L). The anemia was not transplantable, as wild-type mice reconstituted with Smad4(Delta/Delta) bone marrow cells had normal peripheral blood counts. These mice did not develop an inflammatory disease typical for mice deficient in TGF-beta receptors I and II, suggesting that the suppression of inflammation by TGF-beta is Smad4 independent. The same results were obtained when Smad4 alleles were deleted selectively in hematopoietic cells using the VavCre transgenic mice. In contrast, lethally irradiated Smad4(Delta/Delta) mice that received wild-type bone marrow cells developed anemia similar to Smad4(Delta/Delta) mice that did not receive a transplant. Liver iron stores were decreased and blood was present in stool, indicating that the anemia was due to blood loss. Multiple polyps in stomach and colon represent a likely source of the bleeding. We conclude that Smad4 is not required for adult erythropoiesis and that anemia is solely the consequence of blood loss.

Topics: Anemia; Animals; Bone Marrow Transplantation; Erythropoiesis; Flow Cytometry; Gastrointestinal Hemorrhage; Intestinal Polyposis; Iron Deficiencies; Liver; Mice; Mice, Transgenic; Polyps; Reverse Transcriptase Polymerase Chain Reaction; Smad4 Protein; Stomach Diseases; Transforming Growth Factor beta

Effects of fractions A and B from enzyme-digested traditional Chinese medicine colla corii asini on mice with 5-fluorouracil-induced anemia were investigated. The purpose of this study was to further understand the hematopoietic activities and mechanisms of colla corii asini. The fractions A and B were administered to anemic mice for 12 days. After confirming the anti-anemic effect of fractions A and B, we examined the effects of fractions A and B on immature granulocyte and erythroid cell activity and plasma cytokine level. Fraction A administration at 2 g/kg and 1 g/kg and fraction B administration at 1.6 g/kg and 0.8 g/kg activated granulocyte and erythrocyte progenitor cells in bone marrow and erythrocyte progenitors in spleen, led to the recovery of white blood cell and red blood cell counts, and increased the percentage of peripheral reticulocytes in red cells. The GM-CSF and EPO production determined by examining GM-CSF mRNA and EPO mRNA in the kidney and liver of the anemic mice were also enhanced. This treatment significantly increased serum GM-CSF and EPO level and lowered serum transforming growth factor (TGF-beta) level. These results suggested that fractions A and B promoted hematopoiesis by activating immature granulocyte and erythroid cells, partly by stimulating GM-CSF and EPO secretion and suppressing TGF-beta release. Identification of a specific peptide or protein is still required for the development of a novel medicine for anemia caused by malignancy or chemotherapy.

Topics: Anemia; Animals; Base Sequence; Bone Marrow; DNA Primers; Enzymes; Erythropoietin; Female; Fluorouracil; Granulocyte-Macrophage Colony-Stimulating Factor; Medicine, Chinese Traditional; Mice; Mice, Inbred ICR; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; Transforming Growth Factor beta

Two variants of this Walker 256 tumor have been previously reported as Walker 256 A and variant AR. The variant A has more aggressive property than variant AR and can induce systemic effects such as anorexia, sodium and water retention, followed by weight loss and death. The mechanisms involved in enhancing tumor regression and progression in this model are still incompletely understood. In the present study, serum and spleen mononuclear cells and tumor cells from animals inoculated with variants A and AR, were isolated to investigate the TGF-beta, IL-12, IFN-gamma and TNF-alpha and relationship with anemia, weight of animals, weight of spleen, volume of tumor and osmotic fragility compared with controls inoculated with Ringer Lactate. Results demonstrate that the group inoculated with variant A, compared to variant AR, shows high levels of TGF-beta gene expression in both tumor tissue and spleen cells, no expression of IFN-gamma and a progressive and higher levels of IL-12 in tumor tissue without inflammatory infiltrate visualized by optical microscopy. These results suggest that the aggressively of variant A is relate to cytokine modulation, facilitating the growth and escape of tumor cells. Furthermore, IL-12 seems to be constitutively expressed in both tumor lineage A and AR.

Topics: Anemia; Animals; Body Weight; Carcinoma 256, Walker; Cytokines; Enzyme-Linked Immunosorbent Assay; Gene Expression; Hemoglobins; Interferon-gamma; Interleukin-12; Male; Organ Size; Osmotic Fragility; Rats; Rats, Wistar; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; Spleen; Transforming Growth Factor beta; Tumor Necrosis Factor-alpha

An ascitic lymphosarcoma (LS-A) of Swiss mice that regressed spontaneously on subcutaneous (s.c.) transplantation was investigated for the mechanism of its progressive growth and host mortality on intraperitoneal (i.p.) transplantation. In vitro studies indicated significant inhibition of LS-A proliferation seeded at higher cell density (>10(4)/ml). Culture supernatants of LS-A caused bi-modal growth effects, the early supernatants (24 h) caused stimulation and the late (72 h) supernatants inhibited LS-A proliferation. The 72-h supernatants also suppressed T and B cell response to mitogens in a dose-dependent manner. Pan anti-transforming growth factor-beta antibody abrogated the inhibitory effects of supernatants. The supernatants contained both latent as well as bio-active form of transforming growth factor-beta1 (TGF-beta1) as determined by ELISA. Mice bearing i.p. ascites tumor had elevated serum TGF-beta1, hemoglobulinemia, splenic lymphopenia, impaired response of the T cells to mitogen and reduced expression of transferrin receptor (CD71) on the bone marrow cells. However, mice which rejected s.c. transplants, did not show significant changes in these parameters. Our studies indicated profound influence of site of tumor growth on tumor progression and host immune system mediated by tumor-derived TGF-beta1. It is possible that human tumors which secrete TGF-beta1 may exhibit similar patho-physiological effects in the host depending on the anatomical site of the tumor.

Topics: Anemia; Animals; Antigens, CD; Antigens, Differentiation, B-Lymphocyte; Ascites; Cell Proliferation; Disease Progression; Hemoglobins; Humans; Injections, Intraperitoneal; Injections, Subcutaneous; Lymphoma, Non-Hodgkin; Lymphopenia; Male; Mice; Mitogens; Receptors, Transferrin; Sarcoma, Experimental; Spleen; T-Lymphocytes; Transforming Growth Factor beta; Transforming Growth Factor beta1; Tumor Cells, Cultured

The natural killer complex (NKC) is a genetic region of highly linked genes encoding several receptors involved in the control of NK cell function. The NKC is highly polymorphic, and allelic variability of various NKC loci has been demonstrated in inbred mice. Making use of BALB.B6-Cmv1r congenic mice, in which the NKC from disease-susceptible C57BL/6 mice has been introduced into the disease-resistant BALB/c background, we show here that during murine malaria infection, the NKC regulates a range of pathophysiological syndromes such as cerebral malaria, pulmonary edema, and severe anemia, which contribute to morbidity and mortality in human malaria. Parasitemia levels were not affected by the NKC genotype, indicating that control of malarial fatalities by the NKC cells does not operate through effects on parasite growth rate. Parasite-specific antibody responses and the proinflammatory gene transcription profile, as well as the TH1/TH2 balance, also appeared to be influenced by NKC genotype, providing evidence that this region, known to control innate immune responses via NK and/or NK T-cell activation, can also significantly regulate acquired immunity to infection. To date, NKC-encoded innate system receptors have been shown mainly to regulate viral infections. Our data provide evidence for critical NKC involvement in the broad immunological responses to a protozoan parasite.

Topics: Anemia; Animals; Antibodies, Protozoan; Brain; Gene Expression Profiling; Interferon-gamma; Killer Cells, Natural; Malaria; Mice; Mice, Inbred BALB C; Mice, Inbred C57BL; Plasmodium berghei; Pulmonary Edema; Transforming Growth Factor beta

Although the roles played by systemic tumour necrosis factor (TNF) and interleukin 1beta (IL-1beta), and their upregulation of intercellular adhesion molecule 1 (ICAM-1), vascular cell adhesion molecule 1 (VCAM-1) and E-selectin, in the pathogenesis of human cerebral malaria (CM) are well established, the role of local cytokine release, in the brain, remains unclear. Immunohistochemistry was therefore used to compare the expression of ICAM-1, VCAM-1, E-selectin, IL-1beta, TNF and transforming growth factor beta (TGF-beta) at light-microscope level, in cryostat sections of cerebral, cerebellar and brainstem tissues collected, post-mortem, from Ghanaian children. Among the 21 children investigated were 10 cases of CM, five of severe malarial anemia (SMA), one of purulent bacterial meningitis (PBM), two of non-central-nervous-system infection (NCNSI) and three children who had no infection (NI) when they died. Parasitised erythrocytes were detected in all of the sections from the cases of fatal malaria (CM and SMA), and sequestered leucocytes were present in most of the sections from the CM cases (but none of the sections from the SMA cases). Significantly elevated vascular expression of all three adhesion molecules investigated was detected in the brains of the 15 cases of fatal malaria and one of the cases of NCNSI (a child with Salmonella septicaemia), and in the malaria cases this showed highly significant co-localization with the areas of erythrocyte sequestration. In terms of the levels of expression of ICAM-1, VCAM-1 and E-selectin, there were, however, negligible differences between the CM and SMA cases. Although TGF-beta showed intravascular and perivascular distribution in all the subjects, its expression was most intense in the PBM case and the CM group. Only in the sections from the PBM and CM cases did TNF and IL-1beta show prominent brain parenchymal staining, in addition to the intravascular and perivascular staining seen in all subjects. The highest observed expression of each of the six antigens studied was in the cerebellar sections of the malaria cases. Endothelial activation in the brain therefore appears to be a feature of fatal malaria and Salmonella sepsis, and in cases of fatal malaria is closely associated with leucocyte sequestration. In the present study, IL-1beta and TNF were only up-regulated in the brains of children with neurodegenerative lesions, whereas TGF-beta was present in all cases.

Topics: Anemia; Cell Adhesion Molecules; Child; Child, Preschool; Cytokines; E-Selectin; Erythrocytes; Female; Humans; Immunohistochemistry; Infant; Intercellular Adhesion Molecule-1; Interleukin-1; Leukocytes, Mononuclear; Malaria, Cerebral; Male; Meningitis, Bacterial; Transforming Growth Factor beta; Vascular Cell Adhesion Molecule-1

Hypertension and anemia may be causes of left ventricular hypertrophy (LVH) in uremia but the molecular mechanism is not known. Uremia was induced in male Spraugue Dawley rats by 5/6 nephrectomy. The following groups of rats were studied for 6 weeks; uremic rats (U) fed ad. lib., control rats (C) pair-fed with U, U rats given hydralazine (100 mg/kg/day) (UH), U rats given erythropoietin (48 U/kg/week, i.p.) (UE). Both diastolic and mean arterial pressures are higher (P < 0.01) in U and UE compared with C whereas both pressures in UH were normalized. Hemoglobin in U was lower than in C, and was normalized in UE. U, UH and UE had higher heart weight/body weight ratios (HW/BW) as well as left ventricular weight/body weight ratios (LV/BW) compared with C (P < 0.01). Compared with U, UH has lower HW/BW and LV/BW (P < 0.05) and UE has normal HW/BW but lower LV/BW than U (P < 0.05). To see if the gene expression in uremic LVH is similar to that described in pressure overload LVH in which mRNA levels of angiotensin converting enzyme (ACE), transforming growth factor-beta1 (TGF-beta1), atrial natriuretic factors (ANF) and skeletal a- actin were increased, we measured these mRNA levels by Northern analysis. TGF-beta1, ACE and alpha-actin mRNA levels were not changed in all 4 groups. ANF mRNA in U and UE was increased 3 fold over C, and normalized in UH. Treatment of anemia with erythropoietin improved uremic LVH but did not change ANF mRNA; whereas treatment of hypertension with hydralazine normalized ANF mRNA but did not completely correct uremic LVH. Thus, gene expression in uremic LVH is distinct from that in pressure-overload LVH, suggesting that other unidentified factor(s) might be involved in uremic LVH.

Topics: Actins; Anemia; Animals; Atrial Natriuretic Factor; Erythropoietin; Gene Expression; Heart Ventricles; Hydralazine; Hypertension; Hypertrophy, Left Ventricular; Male; Peptidyl-Dipeptidase A; Rats; Rats, Sprague-Dawley; RNA, Messenger; Transforming Growth Factor beta; Transforming Growth Factor beta1; Uremia

Myelofibrosis following peripheral T-cell lymphoma has rarely been reported. Described here is a case of peripheral T-cell lymphoma with myelofibrosis and elevated transforming growth factor beta (TGF-beta). A 69 years old male was admitted due to anemia and thrombocytopenia. His bone marrow showed fibrosis and was infiltrated with small lymphoid cells and a few residual normal hematopoietic cells. He had presented with hepatosplenomegaly and left inguinal lymph node swelling. Biopsy of the left inguinal lymph node revealed diffuse mature small lymphoid cells with atypical nuclei. Immunophenotyping of the small lymphoid cells were positive for CD3, CD8, TCR alphabeta and HLA-DR and were negative for CD4, CD19, CD20 and CD56. T-cell receptor beta-chain gene was rearranged in bone marrow cells. He was diagnosed as having peripheral T-cell lymphoma complicated with myelofibrosis. Chemotherapy was administrated which improved his pancytopenia and symptoms. Two years later, anemia and thrombocytopenia developed rather quickly, he died because of progression of myelofibrosis with severe pancytopenia.

Topics: Aged; Anemia; Fatal Outcome; Gene Rearrangement, beta-Chain T-Cell Antigen Receptor; Humans; Immunophenotyping; Lymphoma, T-Cell, Peripheral; Male; Primary Myelofibrosis; Thrombocytopenia; Transforming Growth Factor beta

The phenotype induced by the GATA-1(low) (neodeltaHS) mutation is here further characterized by analyzing the hemopoietic system during the aging (up to 20 months) of a GATA-1(low) colony (135 mutants and 40 normal littermates). Mutants expressed normal hematocrit values (Hct = 45.9 +/- 4.0) until 12 months but became anemic from 15 months on (Hct = 30.9 +/- 3.9; P <.05). Anemia was associated with several markers of myelofibrosis such as the presence of tear-drop poikilocytes and progenitor cells in the blood, collagen fibers in the marrow and in the spleen, and hemopoietic foci in the liver. Semiquantitative reverse transcription-polymerase chain reaction showed that growth factor genes implicated in the development of myelofibrosis (such as osteocalcin, transforming growth factor-beta1, platelet-derived growth factor, and vascular endothelial growth factor) were all expressed in the marrow from the mutants at higher levels than in corresponding normal tissues. The GATA-1(low) mutants experienced a slow progression of the disease because the final exitus was not observed until at least 15 months with a probability of survival more favorable than that of W/Wv mice concurrently kept in the animal facility (P <.001, by Kaplan-Meier analysis). In conclusion, impaired GATA-1 expression may contribute to the development of myelofibrosis, and the GATA-1(low) mutants may represent a suitable animal model for the human disease that may shed light on its pathogenesis.

Topics: Anemia; Animals; Bone Marrow; Collagen; DNA-Binding Proteins; Endothelial Growth Factors; Erythrocytes; Erythroid Precursor Cells; Erythroid-Specific DNA-Binding Factors; Female; Fibroblast Growth Factor 1; GATA1 Transcription Factor; Gene Expression; Hematocrit; Hematopoiesis, Extramedullary; Liver; Lymphokines; Male; Mice; Mice, Inbred C57BL; Mice, Mutant Strains; Mutation; Osteocalcin; Platelet-Derived Growth Factor; Primary Myelofibrosis; Spleen; Transcription Factors; Transforming Growth Factor beta; Vascular Endothelial Growth Factor A; Vascular Endothelial Growth Factors

The intensity of malaria transmission is related to the pattern of malarial disease observed in different regions, but populations may also differ in their underlying predispositions to severe malarial anemia or cerebral malaria. In western Kenya, where severe malarial anemia is much more common than cerebral malaria, the distributions of tumor necrosis factor (TNF)-alpha, interleukin (IL)-10, transforming growth factor (TGF)-beta, IL-6, and interferon (IFN)-gamma alleles were examined in a cohort of young men. The cohort displayed a marked bias toward genotypes associated with low expression of IFN-gamma and IL-6, cytokines that, at high levels, have been implicated in malarial anemia and poor malaria outcomes. By contrast, the frequency of the TNF-alpha -238A allele, which has been associated with severe malarial anemia, was found to be similar to the frequency previously reported in comparison populations in Africa and elsewhere. IFN-gamma and IL-6 genotypes may play roles in the development of severe malaria and could contribute to the relative frequency of severe malarial anemia or cerebral malaria in exposed populations.

Topics: Adolescent; Adult; Alleles; Anemia; Child; Cohort Studies; Genetic Predisposition to Disease; Humans; Interferon-gamma; Interleukin-10; Interleukin-6; Kenya; Malaria, Falciparum; Male; Transforming Growth Factor beta; Tumor Necrosis Factor-alpha

Chronic treatment of mice with transforming growth factor beta 1 (TGF-beta 1) resulted in a dose-dependent inhibition of erythropoiesis. Following 14 daily s.c. injections of 5 or 25 micrograms of TGF-beta 1, a significant degree of anemia was observed. In addition, erythroid progenitor cells were present in reduced numbers in the bone marrow and spleen. Pluripotent stem cells were present in normal numbers in the bone marrow of mice treated with 25 micrograms of TGF-beta 1. However, significantly elevated levels were present in the peripheral blood. Adequate levels of erythropoietin were present in TGF-beta 1-treated mice. Following suspension of treatment with TGF-beta 1, erythropoiesis was restored, and TGF-beta-treated mice were able to compensate the anemia. One week following treatment, only mice treated with 25 micrograms of TGF-beta 1 continued to show evidence of anemia. However, in contrast to 1 day following treatment, these mice had levels of reticulocytes that were significantly above control values. In addition, erythroid progenitor cells had returned to normal levels in the bone marrow and were present in elevated levels in the spleen in both groups of TGF-beta 1 treated mice. The results provide evidence that the anemia associated with sustained TGF-beta 1 treatment is the result, in part, of a reversible inhibition of the maturation of erythroid progenitor cells.

Topics: Anemia; Animals; Bone Marrow Cells; Cells, Cultured; Erythroid Precursor Cells; Erythropoiesis; Erythropoietin; Injections, Subcutaneous; Male; Mice; Mice, Inbred BALB C; Mice, Inbred C3H; Reticulocytes; Spleen; Time Factors; Transforming Growth Factor beta