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1.
Ann Clin Microbiol Antimicrob ; 22(1): 92, 2023 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-37875923

RESUMO

Francisella tularensis is a Gram-negative bacteria, that may cause a zoonotic disease, tularemia. Here, we describe a patient case, where a previously healthy young woman in Northern Finland contacted health care because of fever and headache. Due to the symptoms and lack of further diagnostic tools in primary health care, she was transferred to University Hospital (UH) where ampicillin and ceftriaxone was given empirically. A cerebrospinal fluid sample (CSF) was drawn showing small Gram-negative rods that grew on chocolate agar after 2 days of incubation. Matrix-assisted laser-desorption-ionization time of-flight (Maldi-tof) did not provide identification, but the bacteria was interpreted as sensitive to ciprofloxacin and the treatment was changed to ciprofloxacin. During the time the patient was infected, there were several positive tularemia samples found in the area. Therefore, an in house tularemia nucleic acid method (PCR) was used on the bacterial culture. Additionally, 16S rDNA sequencing was performed and these methods identified the bacteria as F. tularensis. Fortunately, the patient recovered completely with ciprofloxacin and was discharged without any complications. Our case underlines the need to understand the limits of specific diagnostic methods, such as Maldi-tof, used in clinical laboratory settings. It also highlights the need of both clinicians and laboratory staff to be aware of the many clinical presentations of tularemia when working in an endemic area.


Assuntos
Francisella tularensis , Meningite , Tularemia , Feminino , Humanos , Ciprofloxacina/farmacologia , Francisella tularensis/genética , Reação em Cadeia da Polimerase , Tularemia/diagnóstico , Tularemia/tratamento farmacológico , Tularemia/microbiologia
2.
BMC Immunol ; 24(1): 29, 2023 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-37689649

RESUMO

BACKGROUND: . Lack of exposure to the natural microbial diversity of the environment has been linked to dysregulation of the immune system and numerous noncommunicable diseases, such as allergies and autoimmune disorders. Our previous studies suggest that contact with soil material, rich in naturally occurring microbes, could have a beneficial immunoregulatory impact on the immune system in mice and humans. However, differences in the immunomodulatory properties of autoclaved, sterile soil material and non-autoclaved, live soil material have not been compared earlier. RESULTS: . In this study, we exposed C57BL/6 mice to autoclaved and live soil powders that had the same rich microbiota before autoclaving. We studied the effect of the soil powders on the mouse immune system by analyzing different immune cell populations, gene expression in the gut, mesenteric lymph nodes and lung, and serum cytokines. Both autoclaved and live soil exposure were associated with changes in the immune system. The exposure to autoclaved soil resulted in higher levels of Rorγt, Inos and Foxp3 expression in the colon. The exposure to live soil was associated with elevated IFN-γ concentration in the serum. In the mesenteric lymph node, exposure to live soil reduced Gata3 and Foxp3 expression, increased the percentage of CD8 + T cells and the expression of activation marker CD80 in XCR1+SIRPα- migratory conventional dendritic cell 1 subset. CONCLUSIONS: . Our results indicate that exposure to the live and autoclaved soil powders is not toxic for mice. Exposure to live soil powder slightly skews the immune system towards type 1 direction which might be beneficial for inhibiting type 2-related inflammation. Further studies are warranted to quantify the impact of this exposure in experimental type 2 inflammation.


Assuntos
Células Dendríticas , Inflamação , Humanos , Animais , Camundongos , Camundongos Endogâmicos C57BL , Pós , Fatores de Transcrição Forkhead
3.
J Leukoc Biol ; 114(2): 187-194, 2023 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-37224625

RESUMO

Cytokine-mediated mast cell regulation enables precise optimization of their own proinflammatory cytokine production. During allergic inflammation, interleukin (IL)-4 regulates mast cell functions, tissue homing, and proliferation, but the direct role of closely related IL-13 for mast cell activation remains unclear. Previous work has shown that mast cells are potent IL-13 producers, but here we show that mouse mast cells do not directly respond to IL-13 by Stat6 activation, as they do not express measurable amount of IL-13 receptor α1 (IL-4Rα1) messenger RNA. Consequently, IL-4 responses are mediated via type I IL-4R (IL-4/IL4Rα/γC), and IL-4-induced Stat6 activation is abolished in γC-deficient mast cells. Type II IL-4R deficiency (IL-13Rα1 knockout) has no effect on IL-4-induced Stat6 activation. In basophils, both IL-4 and IL-13 induce Stat6 activation in wild-type and γC-deficient cells, while in type II IL-4R-deficient basophils, IL-4 signaling is impaired at low ligand concentration. Thus, mast cell and basophil sensitivity to IL-4/IL-13 is different, and in mast cells, lack of IL-13Rα1 expression likely explains their unresponsiveness to IL-13.


Assuntos
Interleucina-13 , Interleucina-4 , Animais , Camundongos , Citocinas/metabolismo , Interleucina-13/metabolismo , Subunidade alfa1 de Receptor de Interleucina-13/genética , Subunidade alfa1 de Receptor de Interleucina-13/metabolismo , Interleucina-4/farmacologia , Interleucina-4/metabolismo , Mastócitos/metabolismo , Transdução de Sinais , Fator de Transcrição STAT6/genética
4.
Eur J Immunol ; 53(6): e2250246, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37015057

RESUMO

The proprotein convertase subtilisin/kexins (PCSKs) regulate biological actions by cleaving immature substrate proteins. The archetype PCSK, FURIN, promotes the pathogenicity of viruses by proteolytically processing viral proteins. FURIN has also important regulatory functions in both innate and adaptive immune responses but its role in the CD8+ CTLs remains enigmatic. We used a T-cell-specific FURIN deletion in vivo to demonstrate that FURIN promotes host response against the CTL-dependent lymphocytic choriomeningitis virus by virtue of restricting viral burden and augmenting interferon gamma (IFNG) production. We also characterized Furin KO CD8+ T cells ex vivo, including after their activation with FURIN regulating cytokines IL12 or TGFB1. Furin KO CD8+ T cells show an inherently activated phenotype characterized by the upregulation of effector genes and increased frequencies of CD44+ , TNF+ , and IFNG+ cells. In the activated CTLs, FURIN regulates the productions of IL2, TNF, and GZMB and the genes associated with the TGFBR-signaling pathway. FURIN also controls the expression of Eomes, Foxo1, and Bcl6 and the levels of ITGAE and CD62L, which implies a role in the development of CTL memory. Collectively, our data suggest that the T-cell expressed FURIN is important for host responses in viral infections, CTL homeostasis/activation, and memory development.


Assuntos
Coriomeningite Linfocítica , Linfócitos T Citotóxicos , Camundongos , Animais , Linfócitos T CD8-Positivos , Furina/genética , Camundongos Endogâmicos C57BL , Vírus da Coriomeningite Linfocítica , Memória Imunológica
5.
Stem Cells ; 41(5): 505-519, 2023 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-36945068

RESUMO

For adipose stromal/stem cell (ASCs)-based immunomodulatory therapies, it is important to study how donor characteristics, such as obesity and type 2 diabetes (T2D), influence ASCs efficacy. Here, ASCs were obtained from 2 groups, donors with T2D and obesity (dASCs) or nondiabetic donors with normal-weight (ndASCs), and then cultured with anti-CD3/CD28-stimulated allogeneic CD4 T cells. ASCs were studied for the expression of the immunomodulators CD54, CD274, and indoleamine 2, 3 dioxygenase 1 (IDO) in inflammatory conditions. CD4 T cells cultured alone or in cocultures were assessed to evaluate proliferation, activation marker surface expression, apoptosis, the regulatory T cells (Tregs; CD4+ CD25high FOXP3+) frequency, and intracellular cytokine expression using flow cytometry. Modulation of T-cell subset cytokines was explored via ELISA. In inflammatory conditions, the expression of CD54, CD274, and IDO was significantly upregulated in ASCs, with no significant differences between ndASCs and dASCs. dASCs retained the potential to significantly suppress CD4 T-cell proliferation, with a slightly weaker inhibitory effect than ndASCs, which was associated with significantly reduced abilities to decrease IL-2 production and increase IL-8 levels in cocultures. Such attenuated potentials were significantly correlated with increasing body mass index. dASCs and ndASCs comparably reduced CD4 T-cell viability, HLA-DR expression, and interferon-gamma production and conversely increased CD69 expression, the Tregs percentage, and IL-17A production. Considerable amounts of the immunomodulators prostaglandin E2 (PGE2) and IL-6 were detected in the conditioned medium of cocultures. These findings suggest that ASCs obtained from donors with T2D and obesity are receptive to the inflammatory environment and able to modulate CD4 T cells accordingly.


Assuntos
Diabetes Mellitus Tipo 2 , Células-Tronco Mesenquimais , Humanos , Tecido Adiposo/metabolismo , Linfócitos T CD4-Positivos/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Células-Tronco Mesenquimais/metabolismo , Citocinas/metabolismo , Imunomodulação , Obesidade/metabolismo , Proliferação de Células
6.
Cytokine ; 164: 156159, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36809715

RESUMO

Interleukin (IL)-4 and IL-13 are related cytokines with well-known specific roles in type 2 immune response. However, their effects on neutrophils are not completely understood. For this, we studied human primary neutrophil responses to IL-4 and IL-13. Neutrophils are dose-dependently responsive to both IL-4 and IL-13 as indicated by signal transducer and activator of transcription 6 (STAT6) phosphorylation upon stimulation, with IL-4 being more potent inducer of STAT6. IL-4-, IL-13- and Interferon (IFN)-γ-stimulated gene expression in highly purified human neutrophils induced both overlapping and unique gene expression in highly purified human neutrophils. IL-4 and IL-13 specifically regulate several immune-related genes, including IL-10, tumor necrosis factor (TNF) and leukemia inhibitory factor (LIF), while type1 immune response-related IFN-γ induced gene expression related for example, to intracellular infections. In analysis of neutrophil metabolic responses, oxygen independent glycolysis was specifically regulated by IL-4, but not by IL-13 or IFN-γ, suggesting specific role for type I IL-4 receptor in this process. Our results provide a comprehensive analysis of IL-4, IL-13 and IFN-γ -induced gene expression in neutrophils while also addressing cytokine-mediated metabolic changes in neutrophils.


Assuntos
Interleucina-13 , Interleucina-4 , Humanos , Citocinas/metabolismo , Interferon gama/metabolismo , Interleucina-13/farmacologia , Interleucina-13/metabolismo , Interleucina-4/farmacologia , Interleucina-4/metabolismo , Neutrófilos/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
8.
Acta Derm Venereol ; 102: adv00795, 2022 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-36200507

RESUMO

The coronavirus SARS-CoV-2 (COVID-19) pandemic led to major restrictions in daily life and social contacts in Finland in March 2020. The effect of these restrictions on sexually transmitted infections (STIs) is unclear. The aim of this study was to analyse the incidence and positive rates of sexually transmitted infections in Northern Finland between 2020 and 2021 and compare these with the years prior to the pandemic. Numbers of positive Chlamydia trachomatis, HIV and hepatitis C samples were lower in 2020 to 2021 than in previous years, whereas more gonorrhoea and syphilis was found during pandemic than in previous years. The number of new cases of C. trachomatis reported each month decreased in the first months of the pandemic, but exceeded the prior pandemic-level in autumn 2020. When the mean positive sample rates were compared with the years 2015 to 2019, there was a significant decrease in positive C. trachomatis (p < 0.001) and hepatitis C (p < 0.001) sample rates in both 2020 and 2021. The positive rates for Treponema pallidum in 2020 did not differ significantly (p = 0.38) from previous years. In conclusion, these results show that sexually transmitted infections occurred despite recommendations for social distancing during the COVID-19 pandemic. Thus, easy access to STI testing should always be available, even during exceptional circumstances.


Assuntos
COVID-19 , Infecções por Chlamydia , Gonorreia , Infecções por HIV , Hepatite C , Infecções Sexualmente Transmissíveis , Sífilis , Humanos , COVID-19/epidemiologia , Pandemias , Incidência , Finlândia/epidemiologia , SARS-CoV-2 , Infecções Sexualmente Transmissíveis/diagnóstico , Infecções Sexualmente Transmissíveis/epidemiologia , Sífilis/epidemiologia , Chlamydia trachomatis , Infecções por HIV/diagnóstico , Infecções por HIV/epidemiologia , Infecções por Chlamydia/diagnóstico , Infecções por Chlamydia/epidemiologia
9.
Immun Inflamm Dis ; 10(3): e579, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34873877

RESUMO

INTRODUCTION: The hygiene hypothesis suggests that decrease in early life infections due to increased societal-level hygiene standards subjects one to allergic and autoimmune diseases. In this report, we have studied the effect of sterilized forest soil and plant-based material on mouse immune system and gut microbiome. METHODS: Inbred C57Bl/6 mice maintained in normal sterile environment were subjected to autoclaved forest soil-derived powder in their bedding for 1 h a day for 3 weeks. Immune response was measured by immune cell flow cytometry, serum cytokine enzyme-linked immunoassay (ELISA) and quantitative polymerase chain reaction (qPCR) analysis. Furthermore, the mouse gut microbiome was analyzed by sequencing. RESULTS: When compared to control mice, mice treated with soil-derived powder had decreased level of pro-inflammatory cytokines namely interleukin (IL)-17F and IL-21 in the serum. Furthermore, splenocytes from mice treated with soil-derived powder expressed less IL-1b, IL-5, IL-6, IL-13, and tumor necrosis factor (TNF) upon cell activation. Gut microbiome appeared to be stabilized by the treatment. CONCLUSIONS: These results provide insights on the effect of biodiversity on murine immune system in sterile environment. Subjecting mice to soil-based plant and microbe structures appears to elicit immune response that could be beneficial, for example, in type 2 inflammation-related diseases, that is, allergic diseases.


Assuntos
Microbioma Gastrointestinal , Sistema Imunitário , Animais , Citocinas/imunologia , Hipótese da Higiene , Sistema Imunitário/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Plantas/microbiologia , Microbiologia do Solo
10.
J Invest Dermatol ; 142(6): 1565-1575.e17, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-34808240

RESUMO

Type 2 inflammation‒related cytokine IL-13 plays a protective role in experimental papilloma induction in mice. To understand the mechanisms by which IL-13 contributes to papilloma formation, we utilized Il13rα1-knockout (KO) mice in a widely used 7,12-dimethylbenz[a]anthracene/12-O-tetradecanoyl phorbol-13-acetate two-stage skin carcinogenesis protocol that mimics the development of squamous cell carcinoma. KO mice developed more papillomas and significantly faster than wild-type mice. Papilloma development reduced regulatory T cells in wild-type mice but substantially less in KO mice. In line with this, IL-2 and IL-10 levels decreased in wild-type mice but not in KO mice. Furthermore, systemic IL-5 and TSLP levels were elevated, whereas IL-22 was decreased during papilloma formation in the skin of KO mice. Polymorphonuclear myeloid‒derived suppressor cells were decreased in the KO mice at the early phase of papilloma induction. We show that IL-13Rα1 protects from papilloma development in chemically induced skin carcinogenesis, and our results provide further insights into the protective role of functional IL-4 and IL-13 signaling through type II IL-4 receptor in tumor development.


Assuntos
Papiloma , Neoplasias Cutâneas , 9,10-Dimetil-1,2-benzantraceno/toxicidade , Animais , Carcinogênese/genética , Carcinogênese/patologia , Carcinógenos/toxicidade , Interleucina-13/genética , Subunidade alfa1 de Receptor de Interleucina-13 , Camundongos , Camundongos Knockout , Papiloma/induzido quimicamente , Papiloma/genética , Neoplasias Cutâneas/induzido quimicamente , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/metabolismo , Linfócitos T Reguladores/metabolismo , Acetato de Tetradecanoilforbol/toxicidade
11.
PLoS One ; 16(11): e0260204, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34807911

RESUMO

While IFNγ is a well-known cytokine that actively promotes the type I immune response, it is also known to suppress the type II response by inhibiting the differentiation and proliferation of Th2 cells. However, the mechanism by which IFNγ suppresses Th2 cell proliferation is still not fully understood. We found that IFNγ decreases the expression of growth factor independent-1 transcriptional repressor (GFI1) in Th2 cells, resulting in the inhibition of Th2 cell proliferation. The deletion of the Gfi1 gene in Th2 cells results in the failure of their proliferation, accompanied by an impaired cell cycle progression. In contrast, the enforced expression of GFI1 restores the defective Th2 cell proliferation, even in the presence of IFNγ. These results demonstrate that GFI1 is a key molecule in the IFNγ-mediated inhibition of Th2 cell proliferation.


Assuntos
Proteínas de Ligação a DNA/genética , Interferon gama/imunologia , Células Th2/citologia , Fatores de Transcrição/genética , Animais , Ciclo Celular , Proliferação de Células , Células Cultivadas , Regulação para Baixo , Deleção de Genes , Camundongos , Camundongos Endogâmicos C57BL , Células Th2/imunologia , Células Th2/metabolismo
12.
Int J Legal Med ; 132(6): 1713-1718, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29974235

RESUMO

Diabetes mellitus (DM) could cause pilot incapacitation and result in aviation fatalities. The mechanisms could be directly as a consequence of acute hypoglycemia/subacute diabetic ketoacidosis (DKA) or indirectly as an acute cardiovascular event by contributing to the development of atherosclerosis in coronary or carotid and cerebral arteries. In this study, DM-related fatal flight accidents in the US National Transport Bureau's database between years 2011-2016 were analyzed with special emphasis on postmortem (PM) glucose levels and correlation of toxicological reports with anamnestic information on DM. Additionally, autopsy results on coronary arteries were reviewed. In 43 out of 1491 (~ 3%) fatal accidents pilots had DM. Postmortem glucose or glycated hemoglobin percentage (Hb1Ac) was measured in 12 of the 43 cases; while antidiabetic medication was found in 14 of the cases (only two of the cases had both glucose measurements and medication). With the increasing prevalence of DM, a possibility of pilot incapacitation due to DM or complications of DM should be actively studied, even if no anamnestic information of DM was available. While PM hypoglycemia is difficult to assess, we propose a systematic investigation based on measurement of glucose, Hb1Ac%, and ketone bodies, and documentation of atherosclerotic lesions in major arteries to identify or rule out DM as a cause of pilot incapacitation.


Assuntos
Acidentes Aeronáuticos/estatística & dados numéricos , Diabetes Mellitus/epidemiologia , Pilotos , Adulto , Idoso , Glicemia/análise , Doença da Artéria Coronariana/patologia , Diabetes Mellitus/metabolismo , Glucose/metabolismo , Hemoglobinas Glicadas/análise , Humanos , Hipoglicemiantes/sangue , Corpos Cetônicos/sangue , Pessoa de Meia-Idade , Estados Unidos/epidemiologia , Corpo Vítreo/metabolismo
13.
Front Immunol ; 9: 888, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29930549

RESUMO

Interleukin (IL)-4 and IL-13 are related cytokines that regulate many aspects of allergic inflammation. They play important roles in regulating the responses of lymphocytes, myeloid cells, and non-hematopoietic cells. In T-cells, IL-4 induces the differentiation of naïve CD4 T cells into Th2 cells, in B cells, IL-4 drives the immunoglobulin (Ig) class switch to IgG1 and IgE, and in macrophages, IL-4 and IL-13 induce alternative macrophage activation. This review gives a short insight into the functional formation of these cytokine receptors. I will discuss both the binding kinetics of ligand/receptor interactions and the expression of the receptor chains for these cytokines in various cell types; both of which are crucial factors in explaining the efficiency by which these cytokines induce intracellular signaling and gene expression. Work initiated in part by William (Bill) E. Paul on IL-4 some 30 years ago has now grown into a major building block of our current understanding of basic immunology and the immune response. This knowledge on IL-4 has growing clinical importance, as therapeutic approaches targeting the cytokine and its signal transduction are becoming a part of the clinical practice in treating allergic diseases. Just by reading the reference list of this short review, one can appreciate the enormous input Bill has had on shaping our understanding of the pathophysiology of allergic inflammation and in particular the role of IL-4 in this process.


Assuntos
Hipersensibilidade/imunologia , Interleucina-13/imunologia , Subunidade alfa de Receptor de Interleucina-4/imunologia , Interleucina-4/imunologia , Receptores de Interleucina-13/imunologia , Humanos , Imunidade Celular , Interleucina-13/metabolismo , Subunidade alfa1 de Receptor de Interleucina-13 , Interleucina-4/metabolismo , Subunidade alfa de Receptor de Interleucina-4/metabolismo , Linfócitos/imunologia , Linfócitos/metabolismo , Células Mieloides/imunologia , Células Mieloides/metabolismo , Receptores de Interleucina-13/metabolismo , Transdução de Sinais/imunologia
14.
Int J Rehabil Res ; 41(4): 368-372, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29912785

RESUMO

This cross-sectional study assessed international rehabilitation practitioners' views of mental health assessment (MHA), related specifically to assessment tools and needs in the field. We delivered an anonymous web-based survey capturing rehabilitation practioners' perspectives on MHA practices, assessment tools, and needs through the American Congress of Rehabilitation Medicine in the USA and through national rehabilitation networks in Finland and Norway. Altogether, 355 rehabilitation professionals answered the survey. Unmet MHA needs, most often attributed to insufficient time (112/269 responders), were recognized among rehabilitation professionals irrespective of the country of practice. When professional experience was weighed against barriers to conducting MHA, cost was statistically significantly linked to professional experience, with those with less experience viewing cost more as a barrier (P=0.019). Rehabilitation professionals from different professions, in different countries, and working with a variety of clinical populations recognize defined barriers to MHA in rehabilitation.


Assuntos
Nível de Saúde , Inquéritos Epidemiológicos , Internet , Saúde Mental , Reabilitação , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Feminino , Finlândia , Humanos , Comunicação Interdisciplinar , Colaboração Intersetorial , Masculino , Programas de Rastreamento , Pessoa de Meia-Idade , Avaliação das Necessidades
15.
Soc Psychiatry Psychiatr Epidemiol ; 53(5): 537-540, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29275503

RESUMO

PURPOSE: To evaluate the association between two measurement tools (Social and Occupational Functioning Assessment Scale, SOFAS and Sheehan Disability Scale, SDS), returning to work (RTW) and their inter-correlation. METHODS: 132 psychiatric patients referred to assessment of work ability participated. The association between SOFAS and SDS Work to RTW were assessed by logistic regression. Inter-correlations between SOFAS and SDS were assessed with the Spearman's rho correlation coefficient. RESULTS: SOFAS and SDS Work scores were associated with a 1-year RTW and SOFAS and SDS were inter-correlated. CONCLUSIONS: When assigning the ability to work, both subjective and objective measures of function predict RTW.


Assuntos
Transtornos Mentais/psicologia , Retorno ao Trabalho , Avaliação da Capacidade de Trabalho , Adulto , Estudos de Coortes , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Escores de Disfunção Orgânica , Estatísticas não Paramétricas , Adulto Jovem
16.
Immun Inflamm Dis ; 5(3): 280-288, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28497586

RESUMO

INTRODUCTION: R-Ras GTPase has recently been implicated in the regulation of immune functions, particularly in dendritic cell (DC) maturation, immune synapse formation, and subsequent T cell responses. METHODS: Here, we investigated the role of R-Ras in allergen-induced immune response (type 2 immune response) in Rras deficient (R-Ras KO) and wild type (WT) mice. RESULTS: Initially, we found that the number of conventional DC's in the lymph nodes (LNs) was reduced in R-Ras KO mice. The expression of co-stimulatory CD80 and CD86 molecules on these cells was also reduced on DC's from the R-Ras KO mice. However, there was no difference in papain-induced immune response between the R-Ras WT and KO as measured by serum IgE levels after the immunization. Interestingly, neither the DC number nor co-stimulatory molecule expression was different between WT and R-Ras KO animals after the immunization. CONCLUSIONS: Taken together, despite having reduced number of conventional DC's in the R-Ras KO mice and low expression of CD80 on DC's, the R-Ras KO mice are capable of mounting papain-induced IgE responses comparable to that of the WT mice. To our knowledge, this is the first report addressing potential differences in in vivo allergen responses regulated by the R-Ras GTPase.


Assuntos
Hipersensibilidade/imunologia , Imunoglobulina E/imunologia , Papaína/toxicidade , Proteínas ras/deficiência , Animais , Antígeno B7-1/genética , Antígeno B7-1/imunologia , Antígeno B7-2/genética , Antígeno B7-2/imunologia , Células Dendríticas/imunologia , Células Dendríticas/patologia , Hipersensibilidade/genética , Hipersensibilidade/patologia , Camundongos , Camundongos Knockout , Proteínas ras/imunologia
17.
J Immunol ; 198(10): 3909-3918, 2017 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-28404633

RESUMO

Thymic stromal lymphopoietin (TSLP) and IL-7 are related cytokines that mediate growth and differentiation events in the immune system. They signal through IL-7Rα-containing receptors. Target cells of TSLP in Th2 responses include CD4 T cells and dendritic cells (DCs). Although it has been reported that expression of TSLP receptor (TSLPR) on CD4 T cells is required for OVA-induced lung inflammation, DCs have also been shown to be target cells of TSLP. In this study, we show that murine ex vivo splenic DCs are unresponsive to TSLP, as they fail to phosphorylate STAT5, but in vitro overnight culture, especially in presence of IL-4, renders DCs responsive to both TSLP and IL-7. This induced responsiveness is accompanied by dramatic upregulation of IL-7Rα on DCs with little change in expression of TSLPR or of γc In splenic DCs, the induction of IL-7Rα occurs mainly in CD8- DCs. In vivo, we found that IL-4 has a differential regulatory role on expression of IL-7Rα depending on the cell type; IL-4 decreases IL-7Rα expression on CD4 T cells whereas it upregulates the expression on DCs. Our results indicate that the induction of IL-7Rα expression on DCs is critical for TSLP responsiveness and that IL-4 can upregulate IL-7Rα on DCs.


Assuntos
Citocinas/imunologia , Células Dendríticas/imunologia , Regulação da Expressão Gênica , Receptores de Interleucina-7/genética , Receptores de Interleucina-7/imunologia , Animais , Linfócitos T CD4-Positivos/imunologia , Diferenciação Celular , Interleucina-4/genética , Interleucina-4/imunologia , Interleucina-4/farmacologia , Interleucina-7/imunologia , Interleucina-7/farmacologia , Camundongos , Fosforilação , Fator de Transcrição STAT5/metabolismo , Transdução de Sinais , Células Th2/imunologia , Regulação para Cima , Linfopoietina do Estroma do Timo
18.
J Allergy Clin Immunol ; 132(3): 704-712.e10, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23683462

RESUMO

BACKGROUND: IL-13 is a critical effector cytokine for allergic inflammation. It is produced by several cell types, including mast cells, basophils, and TH2 cells. In mast cells and basophils its induction can be stimulated by cross-linkage of immunoglobulin receptors or cytokines. The IL-1 family members IL-33 and IL-18 have been linked to induction of IL-13 production by mast cells and basophils. In CD4 TH2 cells IL-33-mediated production of IL-13 requires simultaneous signal transducer and activator of transcription (STAT) 5 activation. OBJECTIVE: Here we have addressed whether cytokine-induced IL-13 production in mast cells and basophils follows the same logic as in TH2 cells: requirement of 2 separate signals. METHODS: By generating a bacterial artificial chromosome (BAC) transgenic IL-13 reporter mouse, we measured IL-13 production in mast cells and basophils. RESULTS: In mast cells harvested from peritoneal cavities, 2 cytokine signals are required for IL-13 production: IL-33 and IL-3. In bone marrow mast cells IL-13 production requires IL-33, but the requirement for a STAT5 inducer is difficult to evaluate because these cells require the continuous presence of IL-3 (a STAT5 activator) for survival. Poorer STAT5 inducers in culture (IL-4 or stem cell factor) result in less IL-13 production on IL-33 challenge, but the addition of exogenous IL-3 enhances IL-13 production. This implies that bone marrow-derived mast cells, like peritoneal mast cells and TH2 cells, require stimulation both by an IL-1 family member and a STAT5 inducer to secrete IL-13. Basophils follow the same rule; splenic basophils produce IL-13 in response to IL-18 or IL-33 plus IL-3. CONCLUSION: Optimal IL-13 production from mast cells and basophils requires 2 cytokine signals.


Assuntos
Basófilos/imunologia , Citocinas/imunologia , Mastócitos/imunologia , Animais , Basófilos/efeitos dos fármacos , Células da Medula Óssea/citologia , Células Cultivadas , Citocinas/farmacologia , Proteína 1 Semelhante a Receptor de Interleucina-1 , Mastócitos/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Receptores de Interleucina/imunologia , Receptores de Interleucina-18/imunologia , Fator de Transcrição STAT5/imunologia
19.
Nat Chem Biol ; 8(12): 990-8, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23103943

RESUMO

Cytokines dimerize their receptors, with the binding of the 'second chain' triggering signaling. In the interleukin (IL)-4 and IL-13 system, different cell types express varying numbers of alternative second receptor chains (γc or IL-13Rα1), forming functionally distinct type I or type II complexes. We manipulated the affinity and specificity of second chain recruitment by human IL-4. A type I receptor-selective IL-4 'superkine' with 3,700-fold higher affinity for γc was three- to ten-fold more potent than wild-type IL-4. Conversely, a variant with high affinity for IL-13Rα1 more potently activated cells expressing the type II receptor and induced differentiation of dendritic cells from monocytes, implicating the type II receptor in this process. Superkines showed signaling advantages on cells with lower second chain numbers. Comparative transcriptional analysis reveals that the superkines induce largely redundant gene expression profiles. Variable second chain numbers can be exploited to redirect cytokines toward distinct cell subsets and elicit new actions, potentially improving the selectivity of cytokine therapy.


Assuntos
Citocinas/fisiologia , Interleucina-4/análogos & derivados , Interleucina-4/farmacologia , Linfócitos T CD4-Positivos/metabolismo , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular , Células Dendríticas/efeitos dos fármacos , Citometria de Fluxo , Perfilação da Expressão Gênica , Humanos , Fatores Imunológicos/farmacologia , Interleucina-4/química , Mutação/fisiologia , Fenótipo , Fosforilação , Engenharia de Proteínas , Reação em Cadeia da Polimerase em Tempo Real , Receptores de Interleucina-4/efeitos dos fármacos , Fator de Transcrição STAT6/metabolismo , Transdução de Sinais/efeitos dos fármacos , Relação Estrutura-Atividade
20.
Trends Immunol ; 33(12): 598-606, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22959641

RESUMO

Innate immune and differentiated T cells produce signature cytokines in response to cytokine stimulation. Optimal production requires stimulation by an NF-κB inducer, most commonly an interleukin (IL)-1 family member, and a STAT activator. Usually, there is linkage between the IL-1 family member, the activated STAT and the cytokines produced: IFNγ producers respond to the IL-1 family member, IL-18 and IL-12, a STAT4 activator; IL-13 producers respond to IL-33 (although for ILC2 cells this may be replaced by IL-25) and STAT5 activators; for cells producing IL-17A or IL-22, the combination is IL-1 and a STAT3 inducer. Cytokine-induced cytokine production may have broad significance in orchestrating innate responses to distinct infectious agents and in maintaining inflammatory responses after elimination of the inciting antigen.


Assuntos
Imunidade Inata , Interleucinas/imunologia , Linfócitos/imunologia , Basófilos/imunologia , Humanos , Interleucinas/biossíntese , Mastócitos/imunologia , Neutrófilos/imunologia
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