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1.
Nat Commun ; 14(1): 4575, 2023 07 29.
Artigo em Inglês | MEDLINE | ID: mdl-37516771

RESUMO

Vaccination, especially with multiple doses, provides substantial population-level protection against COVID-19, but emerging variants of concern (VOC) and waning immunity represent significant risks at the individual level. Here we identify correlates of protection (COP) in a multicenter prospective study following 607 healthy individuals who received three doses of the Pfizer-BNT162b2 vaccine approximately six months prior to enrollment. We compared 242 individuals who received a fourth dose to 365 who did not. Within 90 days of enrollment, 239 individuals contracted COVID-19, 45% of the 3-dose group and 30% of the four-dose group. The fourth dose elicited a significant rise in antibody binding and neutralizing titers against multiple VOCs reducing the risk of symptomatic infection by 37% [95%CI, 15%-54%]. However, a group of individuals, characterized by low baseline titers of binding antibodies, remained susceptible to infection despite significantly increased neutralizing antibody titers upon boosting. A combination of reduced IgG levels to RBD mutants and reduced VOC-recognizing IgA antibodies represented the strongest COP in both the 3-dose group (HR = 6.34, p = 0.008) and four-dose group (HR = 8.14, p = 0.018). We validated our findings in an independent second cohort. In summary combination IgA and IgG baseline binding antibody levels may identify individuals most at risk from future infections.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Humanos , Vacina BNT162 , Estudos Prospectivos , COVID-19/prevenção & controle , SARS-CoV-2 , Imunoglobulina A , Imunoglobulina G
2.
Vaccines (Basel) ; 10(7)2022 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-35891160

RESUMO

Mumps and rubella are vaccine-preventable viral diseases through the measles-mumps-rubella-varicella (MMRV) vaccine, administered at 12 months and again at 6 years. We assessed the sero-prevalence of mumps and rubella, identified factors associated with sero-negativity, and evaluated concordance between mumps and rubella sero-positivity. A national cross-sectional sero-survey was conducted on samples collected in 2015 by the Israel National Sera Bank. Samples were tested for mumps and rubella IgG antibodies using an enzyme-linked immunosorbent assay. Of 3131 samples tested for mumps IgG, 84.8% (95%CI: 83.5-86.0%) were sero-positive. Sero-negativity for mumps was significantly associated with age (high odds ratios observed in infants younger than 4 years and 20-29 years old subjects). Of 3169 samples tested for rubella IgG antibodies, 95.2% (95%CI: 94.4-95.9%) were sero-positive. Rubella sero-negativity was significantly associated with age (high odds ratios observed in children younger than 4 years old and adults older than 30 years), males, Jews, and others. Concordant sero-positivity for both mumps and rubella viruses was observed in 83.9% of the tested samples. The Israeli population was sufficiently protected against rubella but not against mumps. Since both components are administered in the MMRV vaccine simultaneously, the mumps component has a lower uptake than rubella and quicker waning.

3.
Vaccine ; 40(3): 512-520, 2022 01 24.
Artigo em Inglês | MEDLINE | ID: mdl-34903372

RESUMO

BACKGROUND: Methodologically rigorous studies on Covid-19 vaccine effectiveness (VE) in preventing SARS-CoV-2 infection are critically needed to inform national and global policy on Covid-19 vaccine use. In Israel, healthcare personnel (HCP) were initially prioritized for Covid-19 vaccination, creating an ideal setting to evaluate early real-world VE in a closely monitored population. METHODS: We conducted a prospective study among HCP in 6 hospitals to estimate the effectiveness of the BNT162b2 mRNA Covid-19 vaccine in preventing SARS-CoV-2 infection. Participants filled out weekly symptom questionnaires, provided weekly nasal specimens, and three serology samples - at enrollment, 30 days and 90 days. We estimated VE against PCR-confirmed SARS-CoV-2 infection using the Cox Proportional Hazards model and against a combined PCR/serology endpoint using Fisher's exact test. RESULTS: Of the 1567 HCP enrolled between December 27, 2020 and February 15, 2021, 1250 previously uninfected participants were included in the primary analysis; 998 (79.8%) were vaccinated with their first dose prior to or at enrollment, all with Pfizer BNT162b2 mRNA vaccine. There were four PCR-positive events among vaccinated participants, and nine among unvaccinated participants. Adjusted two-dose VE against any PCR-confirmed infection was 94.5% (95% CI: 82.6%-98.2%); adjusted two-dose VE against a combined endpoint of PCR and seroconversion for a 60-day follow-up period was 94.5% (95% CI: 63.0%-99.0%). Five PCR-positive samples from study participants were sequenced; all were alpha variant. CONCLUSIONS: Our prospective VE study of HCP in Israel with rigorous weekly surveillance found very high VE for two doses of Pfizer BNT162b2 mRNA vaccine against SARS-CoV-2 infection in recently vaccinated HCP during a period of predominant alpha variant circulation. FUNDING: Clalit Health Services.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Vacina BNT162 , Atenção à Saúde , Hospitais , Humanos , Estudos Prospectivos , SARS-CoV-2 , Eficácia de Vacinas , Vacinas Sintéticas , Vacinas de mRNA
4.
Nat Med ; 27(8): 1379-1384, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34127854

RESUMO

The BNT162b2 mRNA vaccine is highly effective against SARS-CoV-2. However, apprehension exists that variants of concern (VOCs) may evade vaccine protection, due to evidence of reduced neutralization of the VOCs B.1.1.7 and B.1.351 by vaccine sera in laboratory assays. We performed a matched cohort study to examine the distribution of VOCs in infections of BNT162b2 mRNA vaccinees from Clalit Health Services (Israel) using viral genomic sequencing, and hypothesized that if vaccine effectiveness against a VOC is reduced, its proportion among breakthrough cases would be higher than in unvaccinated controls. Analyzing 813 viral genome sequences from nasopharyngeal swabs, we showed that vaccinees who tested positive at least 7 days after the second dose were disproportionally infected with B.1.351, compared with controls. Those who tested positive between 2 weeks after the first dose and 6 days after the second dose were disproportionally infected by B.1.1.7. These findings suggest reduced vaccine effectiveness against both VOCs within particular time windows. Our results emphasize the importance of rigorously tracking viral variants, and of increasing vaccination to prevent the spread of VOCs.


Assuntos
Vacinas contra COVID-19/administração & dosagem , COVID-19/virologia , RNA Mensageiro/genética , SARS-CoV-2/patogenicidade , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Vacina BNT162 , COVID-19/epidemiologia , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade
5.
Hum Vaccin Immunother ; 17(5): 1353-1357, 2021 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-33121333

RESUMO

Measles vaccine is administered in Israel as part of the routine childhood immunization program, at ages 1 and 6 years. In this study, we assessed seropositivity of the Israeli population against measles before the onset and propagation of the 2018-2019 measles outbreak. From the Israel Center for Disease Control National Serum Bank, 3,164 samples collected during 2015 were tested for measles antibodies. All the tests were performed using Enzyme-Linked Immunosorbent Assay (ELISA) commercial kit (Enzygnost, Anti-Measles Virus/IgG: Behring, Marburg, Germany). The overall seropositivity rate for measles was 90.7%. The seropositivity rate at 6 months and younger was 48.9%, and decreased to 3.8% among infants aged 6-11 months. Seropositivity increased to 90.7% in the 1-4-year age group, and reached 96.1% for 5-9 year-old children. Our results suggest high immunity in the Israeli population against measles virus, but not high enough to prevent outbreaks because of pockets of specific population groups with low immunization coverage. Infants between ages 6 and 11 months and children younger than 2 years had the lowest seropositivity rates being the age groups with the highest attack rates of measles during the epidemic of 2018. Efforts should be aimed at avoiding any delay in vaccination once a child reaches the age of 1 year and improving immunity levels in children aged 1-4 years.


Assuntos
Sarampo , Anticorpos Antivirais , Criança , Pré-Escolar , Surtos de Doenças , Alemanha , Humanos , Lactente , Israel , Sarampo/epidemiologia , Vacina contra Sarampo , Estudos Soroepidemiológicos
6.
J Diabetes Sci Technol ; 14(2): 284-289, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-30646746

RESUMO

BACKGROUND: Prolonged time elapsing between the blood drawing and separation of the cell mass may result in decreased sample glucose levels due to continuous glycolysis. This can lead to underdiagnoses of hyperglycemic states and overdiagnosis of hypoglycemia. We aimed to evaluate the clinical impact of shortened transit time and earlier centrifugation of laboratory specimens on reported glucose results and diagnosis of clinically significant hypoglycemia (<50 mg/dL) or elevated glucose levels (>100 mg/dL). METHODS: We assessed all fasting-serum glucose tests from the adult population (190 767 subjects) without known diabetes residing in Southern Israel. Before and after intervention periods were compared: 268 359 blood tests were performed during 2009-2010, and 317 336 during 2012-2013. RESULTS: While glucose levels were 94.17 mg/dL ± 14.12 in 2012-2013 versus 83.53 mg/dL ± 14.50 in 2009-2010 (12.75% ± 0.88 increase, P < .001), the difference in glycated hemoglobin levels was statistically significant but clinically negligible: 5.84% ± 0.56 in 2012-2013 versus 5.88% ± 0.56 in 2009-2010 (0.53% ± 0.78 decrease, P < .01). There was an increased likelihood of a glucose result to be above 100 mg/dL following intervention: 9.80% versus 25.90%, P < .001. For clinics distanced over 40 km from the laboratory, age-adjusted odds ratio value was 1.26 (95% CI 1.13, 1.41). The proportion of samples with hypoglycemia values decreased from 0.33% to 0.03% (P < .001). CONCLUSIONS: We demonstrated an important change in glucose values over a two-year period following an improvement of the preanalytic processes. The intervention was related to an increase in the frequency of hyperglycemia results and a decrease in the number of hypoglycemia results. Future administrative projects should consider clinical consequences with involvement of all relevant stakeholders.


Assuntos
Glicemia/análise , Coleta de Amostras Sanguíneas , Hiperglicemia/diagnóstico , Hipoglicemia/diagnóstico , Fase Pré-Analítica , Adulto , Idoso , Coleta de Amostras Sanguíneas/efeitos adversos , Coleta de Amostras Sanguíneas/métodos , Coleta de Amostras Sanguíneas/normas , Jejum/sangue , Feminino , Glicólise/fisiologia , Humanos , Hiperglicemia/sangue , Hiperglicemia/epidemiologia , Hipoglicemia/sangue , Hipoglicemia/epidemiologia , Israel/epidemiologia , Masculino , Pessoa de Meia-Idade , Fase Pré-Analítica/métodos , Fase Pré-Analítica/normas , Valor Preditivo dos Testes , Melhoria de Qualidade , Meios de Transporte
7.
PLoS One ; 12(6): e0179774, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28622360

RESUMO

West Nile Virus (WNV) is endemic in Israel, affecting yearly 40-160 individuals. Israel is located on a central migratory path between Africa and Eurasia and most West Nile Fever (WNF) cases reported in recent years were among residents of the coastal plain. The aim of the study was to evaluate the seroprevalence of WNV among the Israeli population and to assess correlates for WNV infection. A cross-sectional nationwide serologic survey was conducted using 3,145 serum samples collected by the national Israeli serum bank during 2011-2014, representing all age and population groups in Israel. Prevalence rates of WNV IgG antibodies were determined. Logistic regressions models were applied to assess the associations between demographic characteristics and WNV seropositivity. 350 samples were positive to WNV (11.1%; 95%CI: 10.0-12.3%). In the multivariable analysis, there was a significant association between seropositivity and the Arab population group vs. Jews and others (OR = 1.86, 95%CI: 1.37-2.52), the time lived in Israel [50-59 years vs. 0-9 years; OR = 10.80 (95%CI: 1.03-113.46) and ≥60 years vs. 0-9 years; OR = 14.00 (1.32-148.31)] residence area] Coastal Plain, Inland Plain (Shfela) and Great Rift Valley vs. Upper Galilee; OR = 2.24 (95%CI: 1.37-3.65), OR = 2.18 (95%CI: 1.18-4.03), OR = 1.90 (95%CI: 1.10-3.30), respectively [and rural vs. urban settlement (OR = 1.65, 95%CI: 1.26-2.16). People, who reside in the Coastal Plain, Inland Plain and Great Rift Valley, should be aware of the risk of contracting WNV and reduce exposure to mosquito bites, using insect repellents, and wearing protective clothing. The Ministry of Environmental Protection should be active in reducing the mosquito population by eliminating sources of standing water, a breeding ground for mosquitoes.


Assuntos
Modelos Biológicos , Febre do Nilo Ocidental/epidemiologia , Febre do Nilo Ocidental/transmissão , Vírus do Nilo Ocidental , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Estudos Transversais , Feminino , Humanos , Lactente , Recém-Nascido , Israel , Masculino , Pessoa de Meia-Idade , Estudos Soroepidemiológicos , Febre do Nilo Ocidental/sangue
8.
Toxicon ; 68: 1-8, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23499925

RESUMO

Scorpion sting may cause myocardial injury and heart failure (HF). Clinical signs of failure may develop several hours or even days after the sting, while electrocardiography (ECG) and blood examination soon after the sting may be normal. We sought to examine whether normal echocardiographic (echo) examination performed shortly after hospital arrival would exclude subsequent HF. We also sought to check if blood troponin and natriuretic peptide values measured shortly after arrival may predict or exclude subsequent HF. Natriuretic peptide activities have not been measured in scorpion sting victims. We also wanted to check if HF occurs in envenomated young infants. In a 3-year prospective study we looked at the demographic, clinical, laboratory, ECG, and echo data of all patients with general envenomation who arrived at the emergency department (ED) after scorpion sting. Clinical, laboratory, ECG, and echo results on arrival and 24 h after arrival were checked and compared between groups of patients with normal and abnormal echo on arrival. We then looked for differences in clinical course, therapy, and outcome between groups. The study included 98 children aged 80 days to 19 years (median 53.1 months), 25 were below the age of 2 years. Envenomation by the "yellow scorpion"Leiurus quinquestriatus was suspected in 74 cases. Median time between sting and ED arrival was 80 min. Echo was performed on arrival in 93 of the 98 patients, (in 5 occasions it was not performed or not recorded) 74 were normal and 19 were abnormal. Abnormal echo included hypokinesia and low fractional shortening and ejection fraction of the left ventricle. Clinical signs, abnormal ECG, and laboratory results were not discriminative between groups on arrival. Mean troponin T was higher in patients with abnormal echo, but within normal range in 13 of the 19 patients with abnormal echo and above normal in 2 of the 74 patients with normal echo-missing sensitivity and specificity. Mean N-terminal pro B-type natriuretic peptide was above normal in both groups but within normal range in 5 patients with abnormal echo and above normal range in 24 patients with normal echo-missing sensitivity and specificity. None of the patients with normal echo had subsequent HF and none of the children younger than 2 years of age had HF. All patients survived the intoxication and were discharged home without sequel. We conclude that early echo examination is an important procedure. In our study, normal examination excluded subsequent HF. Abnormal examination accelerated cardiac therapy which might have contributed to our favorable outcome. HF did not occur in infants younger than two years of age.


Assuntos
Mordeduras e Picadas/metabolismo , Ecocardiografia , Insuficiência Cardíaca/diagnóstico , Venenos de Escorpião/efeitos adversos , Adolescente , Fator Natriurético Atrial/sangue , Mordeduras e Picadas/complicações , Criança , Pré-Escolar , Diagnóstico Precoce , Feminino , Insuficiência Cardíaca/etiologia , Humanos , Lactente , Masculino , Estudos Prospectivos , Precursores de Proteínas/sangue , Troponina/sangue , Adulto Jovem
9.
Acta Diabetol ; 49(2): 137-43, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21688017

RESUMO

Kidneys play an important role in retinol turnover. We postulated that retinol homeostasis is disturbed in diabetic nephropathy. The aim of this research was to study the effect of kidney impairment on urinary excretion and on serum concentrations of retinol in type 2 diabetes mellitus patients. For this purpose, 41 type 2 diabetes patients and 9 sex -and age-matched healthy subjects were enrolled. Serum and urinary retinol and retinol-binding protein (RBP) were assessed by high-pressure liquid chromatography and enzyme-linked immunosorbent assay, respectively. The study showed that 17 out of 41 diabetic patients (41.5%) and none of the controls excreted retinol in urine (P < 0.02). Retinol excretion in the urine in these patients was 1.5-fold more prevalent than hypercreatininemia. Urinary retinol significantly correlated with clinically diagnosed nephropathy (P = 0.02). All but one of the patients with hypercreatininemia excreted retinol in the urine. Serum retinol and RBP in patients with hypercreatininemia were higher than in controls (P < 0.002). Values of urinary retinol, unlike urinary RBP, albumin and total protein, did not overlap between patients and controls. Our results indicate that (i) urinary retinol is a specific sign of tubular damage in type 2 diabetic patients and (ii) urinary retinol enables a more clear-cut identification of proximal tubule dysfunction in type 2 diabetes patients than urinary RBP or albumin.


Assuntos
Diabetes Mellitus Tipo 2/fisiopatologia , Nefropatias Diabéticas/diagnóstico , Rim/fisiopatologia , Vitamina A/urina , Estudos de Casos e Controles , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/urina , Nefropatias Diabéticas/sangue , Nefropatias Diabéticas/etiologia , Nefropatias Diabéticas/urina , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Proteínas de Ligação ao Retinol/metabolismo , Vitamina A/sangue
10.
Intensive Care Med ; 35(7): 1255-60, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19205663

RESUMO

OBJECTIVE: To determine if statin therapy reduces the incidence of severe sepsis and the levels of inflammatory cytokines in patients with acute bacterial infection. DESIGN: Double-blind placebo controlled randomized clinical trial. SETTING: Department of medicine and medical intensive care unit in a tertiary university medical center. PATIENTS AND PARTICIPANTS: A total of 83 patients with suspected or documented bacterial infection were enrolled. We randomly assigned 42 patients to receive 40 mg of simvastatin orally, followed by 20 mg of simvastatin, and 41 to receive matching placebo. MEASUREMENTS AND RESULTS: The study was prematurely terminated due to slow recruitment rate. Here we report the analysis of the secondary outcome: change in cytokines levels at 72 h. Both groups were evenly matched in terms of co-morbidity and severity of illness on admission. Four of the 83 patients enrolled developed severe sepsis, two in each group. No difference was observed in other clinical variables and there were no mortalities. Cytokine levels were randomly assessed in 40 patients (20 in each group). Both TNF-alpha and IL-6 levels were significantly reduced in the simvastatin group (p = 0.02 and p = 0.02, respectively), while no such difference was observed in the placebo group (p = 0.35 and 0.39, respectively). CONCLUSIONS: Statin therapy may be associated with a reduction in the levels of inflammatory cytokines in patients with acute bacterial infections. Large controlled trials will determine if this reduction will translate into a clinical benefit.


Assuntos
Infecções Bacterianas/tratamento farmacológico , Citocinas/efeitos dos fármacos , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Sinvastatina/farmacologia , Idoso , Idoso de 80 Anos ou mais , Citocinas/biossíntese , Citocinas/imunologia , Método Duplo-Cego , Feminino , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/administração & dosagem , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Mediadores da Inflamação/metabolismo , Masculino , Pessoa de Meia-Idade , Sepse/prevenção & controle , Sinvastatina/administração & dosagem , Sinvastatina/uso terapêutico
11.
Oncology ; 75(3-4): 203-14, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18852491

RESUMO

OBJECTIVE: Differentiation therapy with the hormonal form of vitamin D, 1alpha,25-dihydroxyvitamin D(3) (1,25D(3)), is a promising approach to treatment of acute myeloid leukemia (AML); however, 1,25D(3) induces hypercalcemia at pharmacologically active doses. We investigated the in vitro and in vivoantileukemic efficacy of combined treatment with non-toxic doses of a low-calcemic 1,25D(3) analogue, 1,25-dihydroxy-21(3-hydroxy-3-methyl-butyl)-19-nor-cholecalciferol (19-nor-Gemini; Ro27-5646), and rosemary plant agents in a mouse model of AML. METHODS: Proliferation and differentiation of WEHI-3B D- (WEHI) murine myelomonocytic leukemia cellsin vitro were determined by standard assays. Reactive oxygen species, glutathione and protein expression levels were measured by flow cytometry, enzymatic assay and Western blotting, respectively. Systemic AML was developed by intravenous injection of WEHI cells in syngeneic Balb/c mice. RESULTS: 19-nor-Gemini had a higher potency than its parent compounds, Gemini (Ro27-2310) and 1,25D(3), in the induction of differentiation (EC(50) = 0.059 +/- 0.011, 0.275 +/- 0.093 and 0.652 +/- 0.085 nM, respectively) and growth arrest (IC(50) = 0.072 +/- 0.018, 0.165 +/- 0.061 and 0.895 +/- 0.144 nM, respectively) in WEHI cells in vitro, and lower in vivo toxicity. Combined treatment of leukemia-bearing mice with 19-nor-Gemini (injected intraperitoneally) and standardized rosemary extract (mixed with food) resulted in a synergistic increase in survival (from 42.2 +/- 2.5 days in untreated mice to 66.5 +/- 4.2 days, n = 3) and normalization of white blood cell and differential counts. This was consistent with strong cooperative antiproliferative and differentiation effects of low concentrations of 19-nor-Gemini or 1,25D(3) combined with rosemary extract or its major polyphenolic component, carnosic acid, as well as with the antioxidant action of rosemary agents and vitamin D derivatives in WEHI cell cultures. CONCLUSION: Combined effectiveness of 1,25D(3) analogues and rosemary agents against mouse AML warrants further exploration of this therapeutic approach in translational models of human leukemia.


Assuntos
Abietanos/uso terapêutico , Calcitriol/análogos & derivados , Modelos Animais de Doenças , Leucemia Experimental/tratamento farmacológico , Leucemia Mieloide Aguda/tratamento farmacológico , Extratos Vegetais/uso terapêutico , Animais , Antioxidantes/uso terapêutico , Medula Óssea/efeitos dos fármacos , Calcitriol/uso terapêutico , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células , Colecalciferol/análogos & derivados , Colecalciferol/uso terapêutico , Sinergismo Farmacológico , Humanos , Immunoblotting , Camundongos , Camundongos Endogâmicos BALB C , Espécies Reativas de Oxigênio/metabolismo , Rosmarinus/química , Taxa de Sobrevida , Células Tumorais Cultivadas
12.
Br J Nutr ; 96(4): 691-6, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17010228

RESUMO

Leptin, a metabolic regulator of energy expenditure, exerts its peripheral effects primarily by altering lipid metabolism. The exocrine pancreas has a key role in the digestion of dietary lipids, but the role of leptin in regulating pancreatic lipases remains unknown. Using the exocrine pancreas in vitro AR42J cell model, we studied the direct effects of leptin on pancreatic lipase (PL) secretion and on the mRNA levels of PL and PL-related proteins 1 and 2 (PLRP1, PLRP2). Leptin directly, rapidly (within 30 min) and significantly inhibited both the secretion and intracellular activity of PL. Leptin downregulated mRNA levels of PL and PLRP1, and upregulated transcripts of PLRP2. This study provides the first evidence that leptin directly regulates exocrine lipases at the levels of synthesis, activity and secretion. This rapid regulation may be associated with a short-term control of energy balance.


Assuntos
Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Leptina/farmacologia , Lipase/metabolismo , Pâncreas Exócrino/efeitos dos fármacos , Animais , Relação Dose-Resposta a Droga , Lipase/biossíntese , Lipase/efeitos dos fármacos , Lipase/genética , Pâncreas Exócrino/enzimologia , Reação em Cadeia da Polimerase/métodos , RNA Mensageiro/genética , Ratos , Células Tumorais Cultivadas
13.
J Immunol ; 169(3): 1433-43, 2002 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-12133969

RESUMO

Monokine induced by IFN-gamma (Mig; CXC chemokine ligand 9) is an IFN-gamma-inducible CXC chemokine that signals through the receptor CXCR3 and is known to function as a chemotactic factor for human T cells, particularly following T cell activation. The mig gene can be induced in multiple cell types and organs, and Mig has been shown to contribute to T cell infiltration into immune/inflammatory reactions in peripheral tissues in mice. We have investigated the expression and activities of Mig and CXCR3 in mouse cells and the role of Mig in models of host defense in mice. Murine (Mu)Mig functioned as a chemotactic factor for resting memory and activated T cells, both CD4(+) and CD8(+), and responsiveness to MuMig correlated with surface expression of MuCXCR3. Using mig(-/-) mice, we found that MuMig was not necessary for survival after infections with a number of intracellular pathogens. Surprisingly, however, we found that mig(-/-) mice showed reductions of 50-75% in Abs produced against the intracellular bacterium Francisella tularensis live vaccine strain. Furthermore, we found that MuMig induced both calcium signals and chemotaxis in activated B cells, and that B cell activation induced expression of MuCXCR3. In addition, IFN-gamma induced the expression of mumig in APCs, including CD8 alpha(+) and CD8 alpha(-) dendritic cells. Together, our data suggest that Mig and CXCR3 may be important not only to recruit T cells to peripheral inflammatory sites, but also in some cases to maximize interactions among activated T cells, B cells, and dendritic cells within lymphoid organs to provide optimal humoral responses to pathogens.


Assuntos
Anticorpos Antibacterianos/biossíntese , Células Apresentadoras de Antígenos/metabolismo , Linfócitos B/imunologia , Quimiocinas CXC/fisiologia , Peptídeos e Proteínas de Sinalização Intercelular , Ativação Linfocitária , Linfócitos T/fisiologia , Animais , Movimento Celular , Quimiocina CXCL9 , Quimiotaxia de Leucócito , Camundongos , Camundongos Endogâmicos C57BL , RNA Mensageiro/análise , Receptores CXCR3 , Receptores de Quimiocinas/fisiologia
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