Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0023418 (leukemia)
 93,477 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We previously reported that the mice deficient for SPA-1, a Rap1 GTPase-activating protein, developed hematopoietic stem cell disorders. Here, we demonstrate that SPA-1(-/-) mice show an age-dependent increase in B220(high) B1a cells producing anti-dsDNA antibody and lupus-like nephritis. SPA-1(-/-) peritoneal B1 cells revealed the altered Vkappa gene repertoire, including skewed Vkappa4 usage and the significant Igkappa/Iglambda isotype inclusion indicative of extensive receptor editing. Rap1GTP induced OcaB gene activation via p38MAPK-dependent Creb phosphorylation, and consistently, SPA-1(-/-) immature BM B cells showing high Rap1GTP exhibited the augmented expression of OcaB and Vkappa4 genes. SPA-1(-/-) BM cells could transfer the autoimmunity in association with the generation of peritoneal B220(high) B1a cells in Rag-2(-/-) recipients. Finally, a portion of SPA-1(-/-) mice developed B1 cell leukemia with hemolytic autoantibody. Present results suggest that the regulated Rap1 signal in the immature B cells plays a role in modifying the B cell receptor repertoire and in maintaining the self-tolerance.
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PMID:Rap1 signal controls B cell receptor repertoire and generation of self-reactive B1a cells. 1661

Rap1 (Ras-proximity 1), a member of the Ras family of small guanine triphosphatases (GTPases), is activated by diverse extracellular stimuli. While Rap1 has been discovered originally as a potential Ras antagonist, accumulating evidence indicates that Rap1 per se mediates unique signals and exerts biological functions distinctly different from Ras. Rap1 plays a dominant role in the control of cell-cell and cell-matrix interactions by regulating the function of integrins and other adhesion molecules in various cell types. Rap1 also regulates MAP kinase (MAPK) activity in a manner highly dependent on the context of cell types. Recent studies (including gene-targeting analysis) have uncovered that the Rap1 signal is integrated crucially and unpredictably in the diverse aspects of comprehensive biological systems. This review summarizes the role of the Rap1 signal in developments and functions of the immune and hematopoietic systems as well as in malignancy. Importantly, Rap1 activation is tightly regulated in tissue cells, and dysregulations of the Rap1 signal in specific tissues result in certain disorders, including myeloproliferative disorders and leukemia, platelet dysfunction with defective hemostasis, leukocyte adhesion-deficiency syndrome, lupus-like systemic autoimmune disease, and T cell anergy. Many of these disorders resemble human diseases, and the Rap1 signal with its regulators may provide rational molecular targets for controlling certain human diseases including malignancy.
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PMID:Regulation of immune responses and hematopoiesis by the Rap1 signal. 1738 43

In allogeneic hematopoietic cell transplantation (HCT), donor T cell-mediated graft versus host leukemia (GVL) and graft versus autoimmune (GVA) activity play critical roles in treatment of hematological malignancies and refractory autoimmune diseases. However, graft versus host disease (GVHD), which sometimes can be fatal, remains a major obstacle in classical HCT, where recipients are conditioned with total body irradiation or high-dose chemotherapy. We previously reported that anti-CD3 conditioning allows donor CD8(+) T cells to facilitate engraftment and mediate GVL without causing GVHD. However, the clinical application of this radiation-free and GVHD preventative conditioning regimen is hindered by the cytokine storm syndrome triggered by anti-CD3 and the high-dose donor bone marrow (BM) cells required for induction of chimerism. Histone deacetylase (HDAC) inhibitors such as suberoylanilide hydroxamic acid (SAHA) are known to induce apoptosis of cancer cells and reduce production of proinflammatory cytokines by nonmalignant cells. Here, we report that SAHA inhibits the proliferative and cytotoxic activity of anti-CD3-activated T cells. Administration of low-dose SAHA reduces cytokine production and ameliorates the cytokine storm syndrome triggered by anti-CD3. Conditioning with anti-CD3 and SAHA allows induction of chimerism with lower doses of donor BM cells in old nonautoimmune and autoimmune lupus mice. In addition, conditioning with anti-CD3 and SAHA allows donor CD8(+) T cell-mediated GVA activity to reverse lupus glomerulonephritis without causing GVHD. These results indicate that conditioning with anti-CD3 and HDAC inhibitors represent a radiation-free and GVHD-preventative regimen with clinical application potential.
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PMID:HDAC inhibitor reduces cytokine storm and facilitates induction of chimerism that reverses lupus in anti-CD3 conditioning regimen. 1834 43

7-Chloro-5-(4-hydroxyphenyl)-1-methyl-3-(napthalen-2-ylmetyl)-4,5,-dihydro-1H-benzo[b][1,4]diazepin-2(3H)-one (Bz-423) is a proapoptotic 1,4-benzodiazepine that potently suppresses disease in the murine model of lupus by selectively killing pathogenic lymphocytes. In MRL/MpJ-Fas(lpr) (MRL-lpr) mice, Bz-423 overcomes deficient expression of the Fas death receptor and hyperactivation of antiapoptotic phosphatidylinositol 3-kinase (PI3K)-Akt signaling to specifically kill pathogenic CD4(+) T cells. Bz-423 binds to the oligomycin-sensitivity-conferring protein component of the mitochondrial F(0)F(1)-ATPase, which modulates the enzyme leading to formation of superoxide by the mitochondrial respiratory chain. Scavenging this reactive oxygen species blocks all subsequent components of the apoptotic cascade. To gain insight into how apoptotic signaling activated by Bz-423-induced superoxide contributes to the selective depletion of MRL-lpr CD4(+) T cells, we characterized the death mechanism in a CD4(+) T cell leukemia line (Jurkat). Although Bz-423-induced superoxide indirectly inactivates Akt, this response is not required for T cell death. Apoptosis instead results from parallel increases in levels of the proapoptotic Bcl-2 proteins Noxa and Bak leading to specific activation of Bak, mitochondrial outer membrane permeabilization, and a commitment to apoptosis. By directly up-regulating proteins that trigger loss of mitochondrial outer membrane integrity, Bz-423 bypasses defective Fas function and antiapoptotic PI3K-Akt signaling in MRL-lpr CD4(+) T cells. Moreover, because disease-associated abnormalities should sensitize autoreactive CD4(+) T cells to transcriptional up-regulation of Noxa by redox signals and to Bak-dependent apoptosis, the apoptotic mechanism elucidated in Jurkat cells provides important clues into the cell-type- and disease-selective effects of Bz-423 in MRL-lpr mice.
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PMID:Apoptotic signaling activated by modulation of the F0F1-ATPase: implications for selective killing of autoimmune lymphocytes. 1970 92

Raltegravir is a recently, Food and Drug Administration-approved, small-molecule drug that inhibits retroviral integrase, thereby preventing HIV DNA from inserting itself into the human genome. We report here that the activity profile of raltegravir on the replication of murine leukemia virus is similar to that for HIV, and that the drug specifically affects autoimmune disease in mice, in which endogenous retroelements are suspected to play a role. While NZW and BALB/c mice, which do not succumb to autoimmune disease, are not affected by raltegravir, lupus-prone (NZBxNZW) F(1) mice die of glomerulonephritis more than a month earlier than untreated mice. Raltegravir-treated NZB mice, which share the H-2 haplotype with BALB/c mice, but which are predisposed to autoimmune hemolytic anemia, develop auto-antibodies to their red blood cells >3 months earlier than untreated mice of the same strain. Because nonautoimmune mice are not affected by raltegravir, we consider off-target effects unlikely and attribute the exacerbation of autoimmunity to the inhibition of retroviral integrase.
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PMID:Early onset of autoimmune disease by the retroviral integrase inhibitor raltegravir. 1992 37

In this case-report a case of severe fetal anemia of unknown origin is presented. Diagnosis of fetal anemia was made at 24 weeks of gestational age, when fetal ascites was identified. Doppler sonography of medium cerebral artery showed a high systolic speed velocity (ACM-PSV), of 65 cm/s (>1.55 MoM). This value predicts a severe fetal anemia. Funicolocentesis confirmed hyporegenerative anemia, low reticulocytosis and low erythroblastosis. A fetal transfusion was performed. At birth anemia was still present and the baby presented blueberry muffin and liver erythropoietic foci. The blueberry muffin morphology presents as non-blanching, blue-red macules or firm, dome-shaped papules (2-8 mm in diameter). The eruption is often generalized but favors the trunk, head, and neck. Infectious (Toxoplasmosis, Cytomegalovirus, Rubella, Herpes, Parvo, Coxackievirus, Ebstein Barr, Syphilis), hematologic (sferocytosis, alloimmunization, foeto-maternal transfusion), metabolic, neoplastic (congenital leukemia, neuroblastome, congenital rhabdomyosarcome) and systemic (histiocytosis, lupus) pathologies indicated until now as possible disease causes were excluded. In the first day of life the neonate received a RBC transfusion for anemia (Hb=5.1 g/dL; Hct 15,7% at birth), followed within 48-72 hours by rapid disappearance of the rash, that wasn't then histologically examined. During two weeks of hospitalization reticulocytes raised spontaneously from 0.8% to 3.17%. Until two years of age the auxologic and clinical course was regular and the child is now in good health conditions. Due to the absence of systematic disease and the complete regression, no exact diagnosis and prognosis could be established in this case.
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PMID:Benign transient blueberry muffin baby. 2046 86

A large group of diseases of unknown etiology, including leukemia, systemic lupus erythematosus, myelodysplastic disease, multiple sclerosis, amyotrophic lateral sclerosis, and rheumatoid arthritis, all present with some elements of immune system disturbance. The Ehrlichia/anaplasma (EA) are an obscure group of obligate parasitic intracellular pathogens that excrete intracellularly a substance called host transcriptional protein, which can alter transcription in cell division. Infection with EA may lead to changes in transcription in proliferating cells, such as those in the marrow, and alter the biology of the products such as T and B cells. Normally 60% of B cells produced in the marrow may be self reactive, but are eliminated before release from the marrow. Changes in transcription could allow self reactive cells to escape into the peripheral circulation and injure normal tissue, creating the dysfunctions which characterize the different immune system diseases and give them their separate identities. A number of studies previously published, and new information presented here, suggest that EA infections may be an underlying, undiagnosed cause for these and other immune system diseases. This hypothesis, long overlooked, has never been subjected to adequate, rigorous study sufficient to prove or disprove its truth. If so, patients may be treated with antibiotics, and marrow transplant manipulations already used in treatment of diseases such as lupus and leukemia may become more effective.
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PMID:Ehrlichia and bone marrow cells: could Ehrlichial infection explain the unsuspected etiology of some diseases of the immune system? 2166 95

Rituximab is a chimeric mouse-human monoclonal antibody against the CD 20 antigen on the surface of B lymphocytes. It binds to CD20 and causes B cell death by antibody dependant cell-mediated cytotoxicity, complement mediated cytotoxicity and apoptosis. It leads to rapid and sustained depletion of B cells. It is licensed for use in adults with CD20 positive B-cell lymphoma and rheumatoid arthritis. In children, it has been used in a variety of off-label indications with promising results. It has proved useful as salvage therapy in relapsed refractory non-Hodgkins lymphoma and leukemia, and in hematological conditions including chronic immune thrombocytopenic purpura, hemophilia with inhibitors, and autoimmune hemolytic anemia. It has also proved effective in autoimmune conditions like primary systemic vasculitis and systemic lupus erythematosis. Nephrotic syndrome and opsoclonus-myoclonus syndrome are among the emerging indications for rituximab. In solid organ transplantation, rituximab is useful in the prevention and treatment of acute and chronic rejection as well as in post transplantation lymphoproliferative disease. Toxicity includes acute infusion reactions, susceptibility to bacterial infections, and reactivation of viral infections.
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PMID:Rituximab. 2270 Jun 74

We investigated the exposure of jaguar (Panthera onca) populations and domestic carnivores to selected viral infections in the Cerrado, Amazon, and Pantanal biomes of Brazil. Between February 2000 and January 2010, we collected serum samples from 31 jaguars, 174 dogs (Canis lupus familiaris), and 35 domestic cats (Felis catus). Serologic analyses for antibodies to rabies virus, canine distemper virus (CDV), feline immunodeficiency virus (FIV), and for feline leukemia virus (FeLV) antigen were conducted. The jaguars from Cerrado and Pantantal were exposed to rabies virus, while the jaguars from the Pantanal and the dogs from all three areas were exposed to CDV. Two cats from the Amazonian site were antigen-positive for FeLV, but no jaguars had FeLV antigen or FIV antibody. Canine distemper and rabies viruses should be carefully monitored and considered potential threats to these jaguar populations. Currently FIV and FeLV do not appear to represent a health threat for jaguar populations in this area. Domestic dogs and cats in these areas should be vaccinated, and the movement of domestic animals around protected areas should be restricted.
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PMID:Serosurvey for selected viral infections in free-ranging jaguars (Panthera onca) and domestic carnivores in Brazilian Cerrado, Pantanal, and Amazon. 2377 99

The transcription factor Friend leukaemia virus integration 1 (Fli-1) is implicated in the pathogenesis of systemic lupus erythematosus in both human patients and murine models of lupus. Murphy Roths large (MRL)/lpr mice and New Zealand mixed (NZM)2410 mice, murine models of lupus, with decreased expression of Fli-1 had significantly prolonged survival and reduced nephritis. Lupus nephritis is a major cause of mortality and morbidity in patients, and inflammatory cell infiltration plays a key role in the development of the disease. To study how the expression of Fli-1 affects the infiltration of inflammatory cells into the kidneys, we generated congenic enhanced green fluorescent protein (GFP) transgenic MRL/lpr mice. A significantly increased number of GFP-expressing inflammatory cells infiltrated the kidneys of wild-type MRL/lpr mice compared to Fli-1 heterozygous (Fli-1(+/-)) MRL/lpr mice after injection of GFP(+) cells. Expression of inflammatory chemokine mRNA, including chemokine (C-C motif) ligand (CCL)2, CCL3, CCL4 and CCL5, was significantly lower in the kidneys from Fli-1(+/-) MRL/lpr mice compared to wild-type littermates. Numbers of infiltrated cells into the kidneys correlate with expression levels of CCL2, CCL4 and CCL5, but not the titres of anti-dsDNA autoantibodies in these mice. Significantly increased inflammatory cells from wild-type MRL/lpr mice infiltrated into kidneys compared to the cells from Fli-1(+/-) MRL/lpr mice. The chemotaxis of inflammatory cells from Fli-1(+/-) MRL/lpr mice towards each chemokine was decreased significantly compared to inflammatory cells from wild-type MRL/lpr mice in the transwell migration assay in vitro. Our results indicate that Fli-1 affects lupus nephritis development by regulating the expression of chemokines in the kidney and the migration of inflammatory cells.
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PMID:The Friend leukaemia virus integration 1 (Fli-1) transcription factor affects lupus nephritis development by regulating inflammatory cell infiltration into the kidney. 2458 Apr 13


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