losartan-potassium and Anemia--Hemolytic--Autoimmune

A 76-year-old woman was referred to our hospital because of anemia. The laboratory findings revealed hemolysis. Although a direct Coombs test was negative, a high titer of RBC-bound IgG was detected, and a diagnosis of Coombs-negative autoimmune hemolytic anemia was made. She was successfully treated with prednisolone. One year and five months later, she again presented anemia and was diagnosed with pure red cell aplasia. Anti-erythropoietin receptor antibody was detected in the serum. She was treated with cyclosporine and obtained prompt recovery. We herein report this rare case and review the pertinent literature.

Topics: Aged; Anemia, Hemolytic, Autoimmune; Coombs Test; Cyclosporine; Erythropoietin; Female; Glucocorticoids; Humans; Immunosuppressive Agents; Prednisolone; Receptors, Erythropoietin; Red-Cell Aplasia, Pure; Treatment Outcome

Haematological abnormalities are common in systemic lupus erythematosus (SLE) and may be manifested by anaemia of different pathogenesis. The objective of this article was to describe some data concerning autoimmune haemolytic anaemia, aplastic and megaloblastic ones accompanying SLE and also to present erythropoietin (EPO) function in the above mentioned diseases. In SLE many factors are produced which disturb the organism haematological balance both on the peripheral level and in the bone marrow. It is assumed that the autoantibodies produced in SLE are the main cause of anaemia. However it should be considered that quantitative changes in the number of erythrocytes observed in this disease are also caused by chronic inflammatory condition, which as the element of autoimmune disease impairs the endocrine function of the kidneys in EPO production. It influences bone marrow, iron metabolism and then haemopoiesis. Apart from humoral factors the role of mechanisms connected with immune cellular response is also considered.

Topics: Anemia, Aplastic; Anemia, Hemolytic, Autoimmune; Anemia, Megaloblastic; Erythropoietin; Humans; Immunity, Cellular; Kidney; Lupus Erythematosus, Systemic

Haematological abnormalities are common in systemic lupus erythematosus. Anaemia is found in about 50% of patients, with anaemia of chronic disease being the most common form. Impaired erythropoietin response and presence of antibodies against erythropoietin may contribute to the pathogenesis of this type of anaemia. Patients with autoimmune haemolytic anaemia usually belong to a distinct category, which is associated with anticardiolipin antibodies, thrombosis, thrombocytopenia, and renal disease, often in the context of secondary antiphospholipid syndrome. Autoantibodies, T lymphocytes, and deregulation of the cytokine network can affect bone marrow erythropoiesis, leading to anaemia.

Topics: Anemia, Hemolytic, Autoimmune; Autoantibodies; Erythropoietin; Hematopoiesis; Humans; Lupus Erythematosus, Systemic; Recombinant Proteins; T-Lymphocytes

New drugs, recently available for treatment of different forms of anaemia, have somehow changed the therapeutic scenario in paediatric haematology. The aim of this review is to focus on the newest molecules discussing indications, clinical usefulness and related problems. Erythropoietin, the specific growth factor of red cell precursors, is now an established option for anaemia of chronic renal failure, prematurity, bone marrow transplantation and chemotherapy. Anti-CD20 monoclonal antibody, a novel cytotoxic molecule for mature B lymphocytes, has proven to be effective in the treatment of refractory autoimmune cytopenias. Haemoglobin analogues are currently under investigation, in order to obtain a synthetic oxygen-carrier that can substitute blood transfusions. Finally drugs that are able to increase the production of haemoglobin F have been used in thalassemias and haemoglobinopathies. For patients with sickle cell disease, hydroxyurea is no longer an experimental tool; it has given rise to several trials, where it has proven to be effective in terms of both clinical and haematological improvement.

Topics: Adult; Age Factors; Anemia; Anemia, Hemolytic, Autoimmune; Anemia, Sickle Cell; Antibodies, Monoclonal; Antibodies, Monoclonal, Murine-Derived; Antineoplastic Agents; Antisickling Agents; Blood Substitutes; Bone Marrow Transplantation; Butyrates; Child; Clinical Trials as Topic; Erythropoietin; Fetal Hemoglobin; Forecasting; Hemoglobinopathies; Hemoglobins; Humans; Hydroxyurea; Infant, Newborn; Infant, Premature, Diseases; Kidney Failure, Chronic; Organ Transplantation; Rituximab; Thalassemia; Tissue Donors

Anemia is a frequent clinical feature with adverse prognostic effects in patients with chronic lymphocytic leukemia (CLL). It may complicate CLL at any time during the course of the disease. Different factors concur to the occurrence of anemia in CLL, as in other lymphoproliferative diseases: leukemic bone marrow infiltration, the myelosuppressive effect of chemotherapy and inhibiting cytokines, autoimmune phenomena, hypersplenism, a poor nutritional status that leads to folic acid, vitamin B12 and iron deficiency. In addition, a defective endogenous erythropoietin (EPO) production has also been described in patients with lymphoproliferative diseases. The severity of anemia, which may be worsened by an impaired cardiopulmonary function, may profoundly compromise the patients' quality of life and, indirectly, the outcome of cancer bearing patients. Several Authors have reported the clinical activity of recombinant human (rHu)EPO in anemic patients with lymphoproliferative diseases, including CLL. Low serum EPO levels at baseline and EPO levels inappropriately low for the degree of anemia help to identify patients who are likely to respond to EPO. A clear dose-dependent response to EPO has been reported by different Authors and it has been suggested that 5,000 IU should be considered as an appropriate initial dose for the majority of patients. rHuEPO represents a potentially effective and safe therapy for the management of anemia associated with lymphoproliferative diseases. The reduction of red blood cell transfusion requirement, the improvement of quality of life through the remission of fatigue-related anemia are two important results that should be considered in the management of patients with CLL. In prospect, the availability of new rHuEPO molecules with a more prolonged half-life may open new therapeutic avenues.

Topics: Anemia; Anemia, Hemolytic, Autoimmune; Antineoplastic Agents; Bone Marrow; Cytokines; Dose-Response Relationship, Drug; Erythropoiesis; Erythropoietin; Granulocyte-Macrophage Colony-Stimulating Factor; Humans; Hypersplenism; Leukemia, Lymphocytic, Chronic, B-Cell; Lymphoproliferative Disorders; Multicenter Studies as Topic; Nutrition Disorders; Radiotherapy; Randomized Controlled Trials as Topic; Recombinant Proteins; Red-Cell Aplasia, Pure; Treatment Outcome

Topics: AIDS-Related Opportunistic Infections; Anemia; Anemia, Hemolytic, Autoimmune; Antiviral Agents; Bone Marrow Diseases; Erythropoietin; Hematopoietic Cell Growth Factors; HIV Infections; Humans; Neoplasms; Recombinant Proteins

Topics: Anemia, Hemolytic; Anemia, Hemolytic, Autoimmune; Animals; Body Temperature Regulation; Cell Membrane; Cell Survival; Chromium Radioisotopes; Chronic Disease; Endotoxins; Erythrocytes; Erythropoiesis; Erythropoietin; Fever; Hematocrit; Hemolysis; Hot Temperature; Iron; Lipid Metabolism; Mononuclear Phagocyte System; Phagocytosis; Rabbits; Spleen

Topics: Anemia, Hemolytic; Anemia, Hemolytic, Autoimmune; Erythropoietin; Humans; Recombinant Proteins

Topics: Anemia, Hemolytic, Autoimmune; Asthma; beta-Globins; Cell Differentiation; Cell Proliferation; Cells, Cultured; Child; Erythrocytes; Erythropoiesis; Erythropoietin; Exome Sequencing; Gene Expression Regulation; Germ-Line Mutation; Humans; Iron Chelating Agents; Receptors, Erythropoietin; Severity of Illness Index; Signal Transduction; STAT3 Transcription Factor; STAT5 Transcription Factor

With growing use of nivolumab, rare but serious side effects have surfaced in some patients. We present a case of autoimmune haemolytic anaemia that developed after 39 cycles of nivolumab. A 78-year-old man with metastatic lung adenocarcinoma, refractory to multiple lines of chemotherapy was switched to nivolumab. After around 2 years of stable course on nivolumab, he developed transfusion-dependent anaemia with haemoglobin of 8.6 g/dL. Nivolumab was held immediately. Bone marrow biopsy findings were inconclusive of myelodysplastic syndrome. Further testing was suggestive of haemolysis with haptoglobin <10 mg/dL, elevated reticulocyte count and identification of immunoglobulin G antibody. Haemoglobin improved significantly with initiation of 1 mg/kg prednisone in addition to rituximab weekly × four doses. The development of transfusion-dependent anaemia with the exposure to cytotoxic chemotherapy usually raises the question for myelodysplastic syndrome. In contradiction, our patient was diagnosed to have a haematological autoimmune complication related to immunotherapy.

Topics: Adenocarcinoma; Adenocarcinoma of Lung; Aged; Anemia, Hemolytic, Autoimmune; Antibodies, Monoclonal; Antineoplastic Agents; Blood Transfusion; Erythropoietin; Hemoglobin A; Humans; Lung Neoplasms; Male; Nivolumab; Treatment Outcome

Aquaporin-1 (AQP1) is the membrane water channel responsible for changes in erythrocyte volume in response to the tonicity of the medium. As the aberrant distribution of proteins in hereditary spherocytosis (HS) generates deficiencies of proteins other than those codified by the mutated gene, we postulated that AQP1 expression might be impaired in spherocytes. AQP1 expression was evaluated through flow cytometry in 5 normal controls, 1 autoimmune hemolytic anemia, 10 HS (2 mild, 3 moderate, 2 severe, and 3 splenectomized), and 3 silent carriers. The effect of AQP1 inhibitors was evaluated through water flow-based tests: osmotic fragility and hypertonic cryohemolysis. Serum osmolality was measured in 20 normal controls and 13 HS. The effect of erythropoietin (Epo) on AQP1 expression was determined in cultures of erythroleukemia UT-7 cells, dependent on Epo to survive. Independent of erythrocyte size, HS patients showed a lower content of AQP1 in erythrocyte membranes which correlated with the severity of the disease. Accordingly, red blood cells from HS subjects were less sensitive to cryohemolysis than normal erythrocytes after inhibition of the AQP1 water channel. A lower serum osmolality in HS with respect to normal controls suggests alterations during reticulocyte remodeling. The decreased AQP1 expression could contribute to explain variable degrees of anemia in hereditary spherocytosis. The finding of AQP1 expression induced by Epo in a model of erythroid cells may be interpreted as a mechanism to restore the balance of red cell water fluxes.

Topics: Adolescent; Adult; Anemia, Hemolytic, Autoimmune; Aquaporin 1; Biological Transport; Body Water; Cell Line; Child; Child, Preschool; Erythrocyte Membrane; Erythrocytes; Erythropoietin; Gene Expression Regulation; Hemolysis; Heterozygote; Humans; Leukemia, Lymphocytic, Chronic, B-Cell; Middle Aged; Osmolar Concentration; Osmotic Fragility; Spherocytosis, Hereditary; Splenectomy

The clinical outcome, response to treatment, and occurrence of acute complications were retrospectively investigated in 308 primary autoimmune hemolytic anemia (AIHA) cases and correlated with serological characteristics and severity of anemia at onset. Patients had been followed up for a median of 33 months (range 12-372); 60% were warm AIHA, 27% cold hemagglutinin disease, 8% mixed, and 5% atypical (mostly direct antiglobulin test negative). The latter 2 categories more frequently showed a severe onset (hemoglobin [Hb] levels ≤6 g/dL) along with reticulocytopenia. The majority of warm AIHA patients received first-line steroid therapy only, whereas patients with mixed and atypical forms were more frequently treated with 2 or more therapy lines, including splenectomy, immunosuppressants, and rituximab. The cumulative incidence of relapse was increased in more severe cases (hazard ratio 3.08; 95% confidence interval, 1.44-6.57 for Hb ≤6 g/dL; P < .001). Thrombotic events were associated with Hb levels ≤6 g/dL at onset, intravascular hemolysis, and previous splenectomy. Predictors of a fatal outcome were severe infections, particularly in splenectomized cases, acute renal failure, Evans syndrome, and multitreatment (4 or more lines). The identification of severe and potentially fatal AIHA in a largely heterogeneous disease requires particular experienced attention by clinicians.

Topics: Adult; Aged; Anemia, Hemolytic, Autoimmune; Antibodies, Monoclonal, Murine-Derived; Autoantibodies; Erythropoietin; Female; Humans; Immunoglobulins, Intravenous; Immunologic Factors; Immunosuppressive Agents; Male; Middle Aged; Predictive Value of Tests; Retrospective Studies; Rituximab; Severity of Illness Index; Splenectomy; Steroids; Treatment Outcome; Young Adult

A 42-year-old woman with systemic lupus erythematosus was admitted to our hospital because of severe anemia. Her bone marrow was almost normocellular and erythroblasts were nearly absent. Laboratory data showed elevated levels of lactate dehydrogenase and positive findings on Coombs' tests. On the basis of these findings, her anemia was diagnosed as the overlap of pure red cell aplasia with autoimmune hemolytic anemia. Radioimmunoprecipitation assay revealed that her serum was positive for anti-erythropoietin antibodies before therapy. Furthermore, the autoantibodies inhibited proliferation of an erythropoietin-dependent cell line in a dose-dependent manner. Immunosuppressive treatment improved the anemia accompanied with disappearance of the autoantibodies.

Topics: Adult; Anemia, Hemolytic, Autoimmune; Antibody Specificity; Autoantibodies; Bone Marrow; Cell Division; Cell Line; Erythroid Precursor Cells; Erythropoietin; Female; Humans; Immunosuppressive Agents; Lupus Erythematosus, Systemic; Methylprednisolone; Prednisolone; Red-Cell Aplasia, Pure

Gene therapy is being considered for the delivery of therapeutic proteins. We evaluated the delivery of the hormone erythropoietin (EPO) into cynomolgus macaques through intramuscularly administered adeno-associated virus (AAV) vectors. As expected, the animals developed supraphysiologic levels of EPO and polycythemia. However, severe anemia ensued in some animals because of an autoimmune response to endogenous and transgene derived EPO. This is the first example of gene therapy leading to inadvertent auto-immunity in primates.

Topics: Anemia, Hemolytic, Autoimmune; Animals; Autoimmunity; Dependovirus; Drug Evaluation, Preclinical; Erythropoietin; Genetic Therapy; Genetic Vectors; Macaca; Polycythemia; Transgenes

We delivered the homologous erythropoietin (Epo) cDNA driven from a doxycycline-regulated promoter via recombinant adeno-associated virus in skeletal muscle of 9 cynomolgus macaques. Upon induction, rapid supraphysiologic levels of Epo were obtained. Unexpectedly, some individuals developed a profound anemia that correlated with the appearance of neutralizing antibodies against the endogenous Epo. Both the endogenous erythropoietin and vector sequences were identical. This is the first example of the inadvertent development of an autoimmune disease in primates as a result of gene transfer of a gene expressing a self-antigen. It raises some concerns when a therapeutic protein is produced at high levels from an ectopic site.

Topics: Anemia, Hemolytic, Autoimmune; Animals; Autoantibodies; Autoimmunity; Dependovirus; Doxycycline; Drug Evaluation, Preclinical; Erythropoietin; Genetic Therapy; Genetic Vectors; Macaca; Promoter Regions, Genetic

To study the prevalence of different causes of anaemia in patients with systemic lupus erythematosus (SLE) and their associations with immunological and clinical parameters and to evaluate the contribution of erythropoietin (Epo) and anti-erythropoietin (anti-Epo) autoantibodies to the development of SLE anaemia.. 132 SLE patients with anaemia (defined as haemoglobin of 12 g/dl or less for women and 13.5 g/dl or less for men) from among a total of 345 consecutive SLE patients were prospectively enrolled into the study. Standard haematological and immunological tests were performed and serum Epo and anti-Epo antibodies were assayed.. The identified causes were anaemia of chronic disease (ACD) n=49 (37.1%), iron deficiency anaemia (IDA) n = 47 (35.6%), autoimmune haemolytic anaemia (AHA) n = 19 (14.4%) and other causes n = 17 (12.9%). There was significant heterogeneity in the severity of anaemia between the four groups (p<0.01) with AHA cases being on average more severe. The proportion of patients with anticardiolipin antibodies, low complement levels and anti-dsDNA differed significantly among the four groups; these markers were particularly common in patients with AHA, and uncommon in patients with IDA. Twenty one of 100 tested patients had anti-Epo antibodies. Such antibodies were seen practically only in patients with ACD (odds ratio 3.1, p = 0.041) and in patients with high lupus activity (ECLAM) scores (odds ratio 1.27 per point, p = 0.055). Epo response was inadequate in 42.4% and 41.2% of patients with ACD and AHA, respectively.. Anaemia in SLE usually takes the form of ACD and IDA, however autoimmune haemolysis is not uncommon. SLE patients with different causes of anaemia differ in regard to several immunological parameters. Epo response is blunted in anaemic SLE patients, particularly those with ACD and AHA.

Topics: Adult; Anemia; Anemia, Hemolytic, Autoimmune; Anemia, Iron-Deficiency; Autoantibodies; Erythropoietin; Female; Follow-Up Studies; Humans; Lupus Erythematosus, Systemic; Male; Middle Aged; Prospective Studies

Warm autoimmune hemolytic anemia (AIHA) is a condition in which peripheral red blood cell (RBC) destruction is induced by the presence of an autoantibody. Pure red cell aplasia (PRCA) represents an isolated process of decreased erythropoiesis. The combination of both is quite rare, with a very poor prognosis. We describe a patient with isolated splenic lymphoma whose presentation was a combination of AIHA and PRCA. The patient was resistant to all treatment.. Erythroid colony assays were performed, in order to compare the effect of the patient's serum on colonies with that of a normal control.. The patient's serum significantly suppressed normal erythroid colony growth. A red cell eluate revealed the presence of a warm autoantibody.. The patient's serum contained warm autoantibody responsible for peripheral RBC destruction and a humoral factor, perhaps the warm autoantibody, which suppressed bone marrow erythropoiesis. Establishing an early diagnosis, and treatment of the underlying disease might result in a better prognosis.

Topics: Anemia, Hemolytic, Autoimmune; Antineoplastic Agents; Autoantibodies; Cell Division; Coombs Test; Diagnosis, Differential; Erythroid Precursor Cells; Erythropoietin; Female; Humans; Lymphoma; Middle Aged; Red-Cell Aplasia, Pure; Sepsis; Splenectomy; Splenic Neoplasms

Topics: Anemia, Hemolytic, Autoimmune; Erythropoiesis; Erythropoietin; Female; Humans; Kidney; Male; Oxygen; Spherocytes; Spherocytosis, Hereditary

We attempted to define the etiology of anemia in SIV-infected rhesus macaques. Bone marrow culture showed significantly decreased (75% reduction) burst forming unit-erythroid (BFU-E) growth in end-stage SIV+ "sick" animals. Direct antiglobulin tests (DAT) were positive in nine of 35 SIV+ "well" and 14 of 14 SIV+ "sick" monkeys (0 of 25 control animals had positive DATs). In animals with a positive DAT, moderate to severe anemia was observed, as was increased LDH and spherocytosis. Erythropoietin was measured in four control, eight SIV+ "well" and five SIV+ "sick" animals with mean levels of 4.0, 15.4, and 1176 mU/mL (r = .94) in the three groups. These data suggest that the cause of anemia in the SIV-infected rhesus macaque is multifactorial, that there may be a defect in erythropoiesis, and that, serologically, an IgG mediated autoimmune hemolytic anemia is also present.

Topics: Anemia; Anemia, Hemolytic, Autoimmune; Animals; Bone Marrow; Colony-Forming Units Assay; Erythropoiesis; Erythropoietin; Simian Acquired Immunodeficiency Syndrome

To determine whether plasma erythropoietin is increased in fetuses with anemia due to Rh isoimmunization.. Hemoglobin and erythropoietin were measured in samples obtained by funipuncture from 15 fetuses with Rh isoimmunization (gestational age 26.2 +/- 5.0 weeks, mean +/- standard deviation) and from 13 control fetuses (23.1 +/- 6.7 weeks). Hemoglobin and erythropoietin also were determined in umbilical cord blood collected at birth from 20 term fetuses delivered by elective cesarean.. Fetuses with Rh isoimmunization had lower hemoglobin and higher plasma erythropoietin measurements than mid-gestation controls (6.1 +/- 3.9 versus 10.7 +/- 1.5 g/dL and 105.5 +/- 168.1 versus 12.5 +/- 3.1 mU/mL, P < .05, respectively). Hemoglobin and plasma erythropoietin increased with gestational age in control fetuses. There was an inverse association between hemoglobin and plasma erythropoietin in control and Rh-isoimmunized fetuses (r = -0.56, P < .005). Using multiple linear regression, hemoglobin and gestational age were associated independently with plasma erythropoietin (overall F2,25 = 12.3, multiple r2 = 0.49, P < .001). Despite marked decreases in hemoglobin, fetuses below 24 weeks' gestation had minimal increases in plasma erythropoietin compared to fetuses above that gestational age. Mildly anemic Rh-isoimmunized fetuses (hemoglobin 11.6 +/- 2.0 g/dL) delivered vaginally had significantly higher erythropoietin levels in umbilical cord plasma than Rh-isoimmunized fetuses with comparable hemoglobin (10.9 +/- 3.5 g/dL) delivered by elective cesarean without labor (1246 +/- 856 versus 106 +/- 66 mU/mL, respectively, P < .05).. Fetuses with anemia at mid to late gestation respond with increases in plasma erythropoietin, but these changes are substantially attenuated before 24 weeks' gestation.

Topics: Anemia, Hemolytic, Autoimmune; Blood Transfusion, Intrauterine; Erythropoietin; Fetal Blood; Fetal Diseases; Gestational Age; Hemoglobins; Humans; Hydrops Fetalis; Regression Analysis; Rh Isoimmunization

A recently developed enzyme-linked immunosorbent assay (EIAZ, ELISA) using two murine monoclonal anti-erythropoietin antibodies was compared with a radioimmunoassay (RIA) and a commercial in-vitro bioassay, EPOS, for measuring serum erythropoietin (Epo) in humans. Specificity and validity for Epo-EIA and the other two assays were examined. The serum Epo in normal subjects was 18 +/- 12 mU/ml (mean +/- SD, n = 80) for EIA compared with 22.5 +/- 18.5 mU/ml (n = 20) for RIA and 136 +/- 132 mU/ml (n = 14) for the bioassay. The serum Epo concentrations in normals and patients were highly comparable between EIA and RIA for Epo (P less than 0.01, r = 0.95). Epo concentrations by the EIA for normal female and male subjects were 20.5 +/- 13 and 16.5 +/- 10 mU/ml, respectively. Epo levels in patients with secondary polycythaemia or autoimmune haemolytic anaemia were significantly higher than normal subjects by the three methods. Epo levels in patients with chronic renal failure were within the normal range. By the EPOS bioassay, the Epo concentrations of normals and patients with renal failure were significantly higher than expected (136 +/- 132 and 447 +/- 273, respectively). Due to its inherent design, the EPOS bioassay possibly measures bone marrow proliferative activity in response to other serum growth regulators besides erythropoietin and was found to be unsuitable for clinical assessment of Epo. We concluded that the new EIA and RIA were similarly sensitive, reliable and accurate for measurement of serum Epo. The EIA method has the advantage of being less time consuming, more convenient and avoids the use of a radioisotope.

Topics: Adolescent; Adult; Anemia, Hemolytic, Autoimmune; Biological Assay; Dose-Response Relationship, Drug; Enzyme-Linked Immunosorbent Assay; Erythropoietin; Female; Humans; Kidney Failure, Chronic; Male; Middle Aged; Polycythemia; Radioimmunoassay; Recombinant Proteins; Reference Standards; Sensitivity and Specificity

We have evaluated the therapeutic activity of recombinant erythropoietin (rEpo), in comparison with recombinant interleukin-3 (rIL-3) and granulocyte-macrophage colony-stimulating factor (rGM-CSF), on a lethal form of acute anemia resulting from Fc gamma receptor-mediated erythrophagocytosis after a single injection (500 micrograms) of a monoclonal anti-mouse red blood cell (MRBC) autoantibody. Continuous perfusion of rEpo before the administration of anti-MRBC monoclonal antibody completely protected animals from death due to anemia with a rapid recovery, while no protection was obtained by rIL-3 perfusion. In contrast, rGM-CSF perfusion markedly accelerated the progression of anemia and the mortality rate. This was found to result from an enhancement of erythrophagocytosis by Kupffer cells and by polymorphonuclear leukocytes that massively infiltrated the livers. Even after the injection of a sublethal dose (100 micrograms) of anti-MRBC monoclonal antibody, rGM-CSF-perfused mice died of a severe form of acute anemia. Furthermore, we have shown that rEpo was able to treat efficiently a spontaneous form of autoimmune hemolytic anemia in a majority of anemic NZB mice, whereas rGM-CSF markedly aggravated anemia. This may be of clinical importance, because GM-CSF administration could exhibit an adverse effect in some autoimmune diseases that involve autoimmune anemia.

Topics: Anemia, Hemolytic, Autoimmune; Animals; Antibodies, Monoclonal; Autoantibodies; Erythrocytes; Erythropoietin; Granulocyte-Macrophage Colony-Stimulating Factor; Interleukin-3; Kupffer Cells; Mice; Mice, Inbred BALB C; Neutrophils; Phagocytosis; Receptors, Fc; Recombinant Proteins

A new type of IgG serum inhibitor in adult pure red cell aplasia (PRCA) has been investigated. This inhibitor is directed against circulating erythropoietin (Ep) (PRCA type B), rather than the erythroid marrow (PRCA type A). Thus, the IgG inhibitor, after interaction with Ep in solution, is precipitated together with Ep by addition of goat anti-human gamma-globulins. Pre-therapy PRCA serum, although apparently devoid of Ep, shows considerable Ep activity following acidification and boiling. The inhibitor is absent from post-therapy serum, while Ep levels are elevated. An experimental model for PRCA type B has been established in normal mice after prolonged administration of pre-remission serum IgG.

Topics: Aged; Anemia, Hemolytic, Autoimmune; Animals; Antigen-Antibody Reactions; Erythropoietin; Female; Humans; Immunoglobulin G; Mice; Mice, Inbred Strains; Neutralization Tests

Topics: Anemia, Hemolytic; Anemia, Hemolytic, Autoimmune; Anemia, Myelophthisic; Anemia, Sickle Cell; Bone Marrow; Erythropoietin; Heart Diseases; Hematocrit; Humans; Hypoxia; Kidney Diseases; Reticulocytes; Spherocytosis, Hereditary

Topics: Adolescent; Anemia, Aplastic; Anemia, Hemolytic, Autoimmune; Anemia, Hypochromic; Child; Child, Preschool; Erythroblastosis, Fetal; Erythropoietin; Female; Humans; Infant; Infant, Newborn; Kidney Diseases; Male; Pregnancy; Wilms Tumor

Topics: Anemia, Hemolytic, Autoimmune; Autoantibodies; Complement System Proteins; Erythropoietin; Female; Heart; Hemolysis; Humans; In Vitro Techniques; Insulin Antibodies; Ovarian Neoplasms