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Teleost IgT/Z plays a principal role in the defense mechanisms against infectious agents in the mucosal compartments and in systemic immunity. Previously, Nile tilapia (Oreochromis niloticus) IgT was discovered and characterized at transcription level. In this work, we generated a monoclonal antibody (mAb) that specifically recognized the Nile tilapia IgT. BALB/c mice were immunized with three synthetic peptides conjugated to KLH. The sequences of these peptides derived from the constant region of the Nile tilapia IgT heavy chain. ELISA and Western blotting confirmed the specificity of the polyclonal sera and the culture supernatant from a positive hybridoma clone. We observed immunoreactivity against a recombinant IgT fragment and native IgT in skin mucus. The anti-IgT mAb did not cross-react with purified tilapia IgM. Direct ELISA analysis allowed the quantification of skin mucus IgM and IgT concentrations. Flow cytometry analysis revealed differences in the percentage of IgT+ B cell populations between juveniles and adults in peripheral blood, head kidney and spleen lymphocytes and among the tissues analyzed. For further validation of the anti-IgT mAb utility, a recombinant vaccine candidate against sea lice (TT-P0 Ls) was injected into juvenile tilapia. Direct ELISA results revealed a differential secretion of skin mucus IgT and IgM after immunostimulation. In addition, the percentages of IgT+ B cells were determined at 7 days after booster and ex-vivo stimulation by flow cytometry. This mAb constitutes an important immunological tool to study the biological function and structural characteristics of tilapia IgT.
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Tristetraprolin (TTP) is an RNA binding protein that destabilizes mRNAs of factors involved in proliferation, invasiveness, and inflammation. Disruption of the gene that codes for TTP (Zfp36) led to severe arthritis, autoimmunity, cachexia and dermatitis in mice. It has been shown that these phenotypes were mostly due to excessive TNFα levels in the affected tissues. We have previously reported that TTP expression is required for lactation maintenance. Our results indicated that conditional MG TTP-KO female mice displayed early involution due to the untimely induction of pro-inflammatory pathways led mostly by TNFα overexpression. Here we show that reducing TTP levels not only affects the fully differentiated mammary gland, but also harms morphogenesis of this tissue by impairing the progenitor cell population. We found that Zfp36 expression is linked to mammary stemness in human and mice. In addition, diminishing TTP expression and activity induced apoptosis of stem-like mouse mammary cells, reduced its ability to form mammospheres in culture and to develop into complete glands when implanted into cleared mammary fat pads in vivo. Our results show that survival of the stem-like cells is compromised by increased levels of inflammatory cytokines and stimulation of signaling cascades involving NFκB, STAT3 and MAPK-p38 activation. Moreover, TNFα overexpression and the consequent p38 phosphorylation would be the leading cause of progenitor cell death upon TTP expression restriction. Taken together, our results reveal the relevance of TTP for the maintenance of the mammary progenitor cell compartment by maintaining local TNFα levels at bay.
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OBJECTIVES: TTP488, an antagonist of the receptor for advanced glycation end-products, was evaluated as a potential treatment for patients with mild-to-moderate Alzheimer's disease (AD). However, the mechanism underlying the protective action of TTP488 against AD has not yet been fully explored. METHODS: Healthy male rats were exposed to aberrant amyloid β (Aβ) 1-42. Lipopolysaccharide (LPS) and the NOD-like receptor family pyrin domain containing 1 (NLRP1) overexpression lentivirus were injected to activate the NLRP1 inflammasome and exacerbate AD. TTP488 was administered to reverse AD injury. Finally, tofacitinib and fludarabine were used to inhibit the activity of Janus tyrosine kinase (JAK) and signal transducer and activator of transcription (STAT) to prove the relationship between the JAK/STAT signaling pathway and TTP488. RESULTS: LPS and NLRP1 overexpression significantly increased the NLRP1 levels, reduced neurological function, and aggravated neuronal damage, as demonstrated by the impact latency time of, time spent by, and length of the platform covered by, the mice in the Morris water maze assay, Nissl staining, and immunofluorescence staining in rats with AD. CONCLUSIONS: TTP488 administration successfully reduced AD injury and reversed the aforementioned processes. Additionally, tofacitinib and fludarabine administration could further reverse AD injury after the TTP488 intervention. These results suggest a new potential mechanism underlying the TTP488-mediated alleviation of AD injury.
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Animais , Masculino , Camundongos , Ratos , Janus Quinases/metabolismo , Doença de Alzheimer/tratamento farmacológico , Tirosina , Transdutores , Transdução de Sinais , Peptídeos beta-Amiloides , Janus Quinase 2 , Receptor para Produtos Finais de Glicação Avançada , ImidazóisRESUMO
It has been established that ZFP36 (also known as Tristetraprolin or TTP) promotes mRNA degradation of proteins involved in inflammation, proliferation and tumor invasiveness. In mammary epithelial cells ZFP36 expression is induced by STAT5 activation during lactogenesis, while in breast cancer ZFP36 expression is associated with lower grade and better prognosis. Here, we show that the AP-1 transcription factor components, i.e. JUN, JUNB, FOS, FOSB, in addition to DUSP1, EGR1, NR4A1, IER2 and BTG2, behave as a conserved co-regulated group of genes whose expression is associated to ZFP36 in cancer cells. In fact, a significant down-modulation of this gene network is observed in breast, liver, lung, kidney, and thyroid carcinomas compared to their normal counterparts. In breast cancer, the normal-like and Luminal A, show the highest expression of the ZFP36 gene network among the other intrinsic subtypes and patients with low expression of these genes display poor prognosis. It is also proposed that AP-1 regulates ZFP36 expression through responsive elements detected in the promoter region of this gene. Culture assays show that AP-1 activity induces ZFP36 expression in mammary cells in response to prolactin (PRL) treatment thorough ERK1/2 activation. These results suggest that JUN, JUNB, FOS and FOSB are not only co-expressed, but would also play a relevant role in regulating ZFP36 expression in mammary epithelial cells.
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Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/patologia , Mama/metabolismo , Regulação Neoplásica da Expressão Gênica , Redes Reguladoras de Genes , Fator de Transcrição AP-1/metabolismo , Tristetraprolina/metabolismo , Biomarcadores Tumorais/genética , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Biologia Computacional/métodos , Feminino , Humanos , Prognóstico , Fator de Transcrição AP-1/genética , Tristetraprolina/genéticaRESUMO
ABSTRACT Background: Thrombotic thrombocytopenic purpura (TTP) is a potentially fatal disease that requires early diagnosis and treatment that can be made possible by applying the PLASMIC score. This study aims to evaluate this score applicability for patients with suspected TTP in a developing country. Methods: This was a retrospective study performed at a tertiary hospital in the northeastern region of Brazil. Patients were analyzed in two groups: ADAMTS13 activity <10% and activity >10%. Patients were stratified according to the PLASMIC score, and the level of agreement between the PLASMIC score and the ADAMTS13 activity was evaluated. Results: Eight patients with thrombotic microangiopathy were included. Four patients had ADAMTS13 activity <10%, all with a PLASMIC score =6. The other four had ADAMTS13 activity >10%, all with a score <6. Based on a score =6 for presumptive diagnosis of TTP, we attained a 100% diagnostic accuracy in our sample. The PLASMIC score was also able to accurately predict response to plasma exchange and the risk of long-term unfavorable outcomes. Conclusions: The reproducibility of the PLASMIC score was quite satisfactory in our sample. It accurately discriminates between patients who had ADAMTS13 deficiency and those with normal enzyme activity, precluding the need for specific laboratory evaluation, which is not always available. This score can be useful for an early diagnosis and indicates which patients will benefit from the treatment in developing countries.
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Humanos , Masculino , Feminino , Gravidez , Adolescente , Adulto , Pessoa de Meia-Idade , Púrpura Trombocitopênica Trombótica , Ativador de Plasminogênio Tecidual , Microangiopatias Trombóticas/terapia , Proteína ADAMTS13RESUMO
BACKGROUND: Thrombotic thrombocytopenic purpura (TTP) is a potentially fatal disease that requires early diagnosis and treatment that can be made possible by applying the PLASMIC score. This study aims to evaluate this score applicability for patients with suspected TTP in a developing country. METHODS: This was a retrospective study performed at a tertiary hospital in the northeastern region of Brazil. Patients were analyzed in two groups: ADAMTS13 activity <10% and activity >10%. Patients were stratified according to the PLASMIC score, and the level of agreement between the PLASMIC score and the ADAMTS13 activity was evaluated. RESULTS: Eight patients with thrombotic microangiopathy were included. Four patients had ADAMTS13 activity <10%, all with a PLASMIC score =6. The other four had ADAMTS13 activity >10%, all with a score <6. Based on a score =6 for presumptive diagnosis of TTP, we attained a 100% diagnostic accuracy in our sample. The PLASMIC score was also able to accurately predict response to plasma exchange and the risk of long-term unfavorable outcomes. CONCLUSIONS: The reproducibility of the PLASMIC score was quite satisfactory in our sample. It accurately discriminates between patients who had ADAMTS13 deficiency and those with normal enzyme activity, precluding the need for specific laboratory evaluation, which is not always available. This score can be useful for an early diagnosis and indicates which patients will benefit from the treatment in developing countries.
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BACKGROUND: Thrombotic thrombocytopenic purpura (TTP) is a hematologic disease that can be fatal if not treated early. We aimed to describe the clinical characteristics of Mexican patients with idiopathic TTP. STUDY DESIGN AND METHODS: We conducted a retrospective study, including all adult patients diagnosed with idiopathic TTP from 2011 to 2017 in two Mexican centers. We further compared our results with the published literature. RESULTS: Twenty patients were included; 70% were female, with a median age of 38.5 years at diagnosis (range 16-63). The median time from onset of symptoms to hospital admission was 1.5 days (range 0-16). Most patients (85%) presented with at least one systemic manifestation at admission (including fever) and 90% had neurological symptoms, most of them major (70%) including loss of consciousness, transient focal abnormalities, headache, and confusion. Only one patient (5%) had the classical pentad at the time of admission. Kidney failure was present in 25% of patients and hemorrhagic symptoms in 60%. Digestive and cardiorespiratory symptoms were less common (45% and 15%, respectively). Median platelet count and lactate dehydrogenase were 10 500/µL and 1319 IU/L, respectively. Eighty percent of patients achieved remission following treatment. Patients admitted within the first 48 hours (after the onset of symptoms) tended to have better overall survival. CONCLUSION: Clinical presentation in Mexican TTP patients is similar to that in other countries. Early admission and a high suspicion for the disease will avoid delays in the initial work-up and initiation of therapy, further improving prognosis.
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Púrpura Trombocitopênica Trombótica/diagnóstico , Púrpura Trombocitopênica Trombótica/terapia , Adolescente , Adulto , Diagnóstico Precoce , Feminino , Humanos , Masculino , México , Pessoa de Meia-Idade , Prognóstico , Púrpura Trombocitopênica Trombótica/patologia , Estudos Retrospectivos , Prevenção Secundária , Adulto JovemRESUMO
INTRODUCTION: Thrombotic thrombocytopenic purpura (TTP) is characterized by a reduction in the von Willebrand cleavage protein ADAMTS-13, mainly as a consequence of autoimmunity. Plasma exchange (PEx) is standard, achieving complete remission (CR) in 77-83% of cases, but rates are variable depending on ADAMTS-13 activity and relapse is frequent in patients with <10%. Thus, an effective front-line immunosuppressive treatment is needed. MATERIALS AND METHODS: We administered PEx daily until CR and rituximab 100 mg/dose/week for 4 consecutive weeks to 10 patients with a first TTP episode and 1 relapsed patient (8 females (72%) and 3 males (28%)). Median age was 34 years (15-46) and laboratory parameters at diagnosis were as follows: platelets 11 × 10(9)/l (range 7-27.4 × 10(9)/l), lactate dehydrogenase 1822â U/l (range 705-8220â U/l, normal 70-180â U/l), and haemoglobin 6â g/dl (range 4.2-11.8â g/dl). ADAMTS-13 activity was determined in eight patients and was <10% in all. ADAMTS-13 autoantibody titre was determined in seven patients and was >15â units/ml in all (ref: negative <12, undetermined 12-15, positive >15â units/ml); Shiga toxin was negative in all patients. The median number of PEx until CR was 7 (range 4-12); prednisone 1â mg/kg was administered to six patients. RESULTS: The median follow-up was 22 months (range 4-49) and the estimated 2-year relapse-free survival was 89%; one HIV+ patient relapsed at 8 months follow-up. No complications related to PEx or rituximab were reported. CONCLUSIONS: Our study suggests that low-dose rituximab and PEx are effective as front-line treatment for acute TTP; however, a prospective trial is needed to demonstrate whether low-dose rituximab is as effective as the conventional dose.
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Troca Plasmática , Púrpura Trombocitopênica Trombótica/mortalidade , Púrpura Trombocitopênica Trombótica/terapia , Rituximab/administração & dosagem , Adolescente , Adulto , Intervalo Livre de Doença , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Taxa de SobrevidaRESUMO
A patient being treated for metastatic adenocarcinoma of the pancreas presents to the clinic for a routine appointment. A complete blood count reveals hemoglobin of 6.5 g/dl and a platelet count of 30,000 K/mm3 thought to be from the last of many doses of gemcitabine. On assessment, the only complaint was fatigue with no evidence of bleeding or other abnormal physical findings other than pallor. Past medical history includes hypertension managed with three antihypertensive agents. Additional laboratory tests reveal elevated blood urea nitrogen (69 mg/dl), creatinine (2.76 mg/dl), and lactic dehydrogenase (LDH), was well as indirect bilirubin (2.1 mg/dl). The patient is admitted and transfused with packed red blood cells (pRBCs). The next day, the platelet count drops to 9,000 K/mm3 and the hemoglobin increases, appropriately, to 8.9 g/dl. Urinalysis is positive for hemoglobin (+ 3). The peripheral blood smear is positive for schistocytes (fragmented RBCs). A pheresis catheter is placed after the patient was evaluated by a hematologist and a nephrologist. A presumptive diagnosis of thrombotic thrombocytopenic purpura (TTP) with hemolytic uremic syndrome (HUS) was made.