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1.
Int J Mol Sci ; 24(3)2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36769064

RESUMO

CD56+ T cells are generally recognized as a distinct population of T cells and are categorized as NKT-like cells. Although our understanding of NKT-like cells is far from satisfactory, it has been shown that aging and a number of disease situations have impacted these cells. To construct an overview of what is currently known, we reviewed the literature on human NKT-like cells. NKT-like cells are highly differentiated T cells with "CD1d-independent" antigen recognition and MHC-unrestricted cell killing. The genesis of NKT-like cells is unclear; however, it is proposed that the acquisition of innate characteristics by T cells could represent a remodeling process leading to successful aging. Additionally, it has been shown that NKT-like cells may play a significant role in several pathological conditions, making it necessary to comprehend whether these cells might function as prognostic markers. The quantification and characterization of these cells might serve as a cutting-edge indicator of individual immune health. Additionally, exploring the mechanisms that can control their killing activity in different contexts may therefore result in innovative therapeutic alternatives in a wide range of disease settings.


Assuntos
Células T Matadoras Naturais , Humanos , Antígenos CD1d , Células Matadoras Naturais , Envelhecimento
2.
Front Genet ; 13: 952219, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36313452

RESUMO

Leprosy is a chronic disease and also a global health issue, with a high number of new cases per year. Toll-like receptors can respond to mycobacterial molecules in the early stage of infection. As important components of the innate immune response, alterations in genes coding for these receptors may contribute to susceptibility/protection against diseases. In this context, we used a case-control study model (183 leprosy cases vs. 185 controls) to investigate whether leprosy patients and the control group, in southern Brazil, have different frequencies in TLR1 (TLR1 G>T; rs5743618), TLR2 (TLR2 T>C, rs1816702 and rs4696483), and TLR4 (TLR4 A>G, rs1927911) polymorphisms. Analysis of the TLR1 1805G>T polymorphism presented the G/G genotype more frequently in the control group. TLR2 T>C rs1816702 and TLR2 T>C rs4696483, the T/T and C/T genotype, respectively, were more frequent in the control group than in leprosy patients, suggesting protection from leprosy when the T allele is present (rs4696483). Haplotype analyses between TLR1 (rs5743618) and TLR2 (rs1816702 and rs4696483) polymorphisms suggest risk for the presence of the TCC haplotype and protection in the presence of the TCT haplotype. This study suggests that polymorphisms in TLR1 and TLR2 are factors that may contribute to development/resistance of leprosy.

3.
J Pers Med ; 12(3)2022 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-35330342

RESUMO

The role of the immune system, and hence inflammation, in the pathophysiology of hypertensive patients is not clear. Until now, most clinical and biochemical parameters have failed to predict a positive response to renal denervation (RDN). Our aim was to evaluate the immune response in a cohort of patients treated by RDN, through the analysis of cytokine, chemokine, and growth factor behavior. A population of 21 resistant hypertension patients, treated by RDN, was evaluated at six months and one year. Response was defined as a drop of ≥5 mmHg in ambulatory blood pressure monitoring. Sixty-seven percent and 81% of patients clinically responded after six months and one year, respectively. There were no complications or safety issues. Plasmatic levels of 45 cytokine, chemokine, and growth factors were quantified at four different times, pre- and post-procedure. Baseline characteristics were similar between groups, except that active smoking was more frequent in non-responders at one year. Regulated on activation, normal T cell expressed, and secreted (RANTES/CCL5) levels were significantly lower in responders, both at baseline and at 30 days (p = 0.037), and a level ≤15,496 pg/mL was the optimal cutoff, for prediction of a response. IL-15, IL-17A, IL-27, and leukemia inhibitory factor varied significantly in time, with an acute rise being observed 24 h after RDN. Our group has previously showed that HLA-DR+ double-negative (DN) T cells were significantly lower in responders. There was a positive correlation between IL-13, -27, and -4, and DN T cells, and a negative correlation between the latter and SDF-1α and TNF-α, at baseline. Low plasmatic levels of the chemokine RANTES/CCL5 was the most significant result associated with RDN response and may help to identify the best candidates among patients with true resistant hypertension. Pro-inflammatory cytokines correlated negatively with DN T cells in responders, a finding compatible with an enhanced inflammatory milieu present in this extremely high cardiovascular risk cohort.

4.
Cancers (Basel) ; 13(23)2021 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-34885185

RESUMO

Osteosarcoma (OST) is the most common type of high-grade primary bone tumor, which mainly affects young adults. The current standard of care for OST combines surgical resection with chemotherapy. The clinical outcomes and the current options to treat OST patients are unsatisfactory and novel treatment strategies are needed. The crosstalk between tumor cells and immune cells is essential to the OST microenvironment. Despite the efforts that have been made to address the importance of immune-related factors in OST, there is still a lot to understand. The purpose of the current study was to evaluate the tumor-infiltrating lymphocytes (TIL), the expression of proteins involved in tumor biology, and their impact on the clinical outcome of OST patients. We studied 93 samples of OST patients using immunohistochemistry and histomorphometry. We looked for the infiltration of CD3+, CD4+, CD8+, TIA1+ and CD20+ cells and for the expression of CD44 standard (CD44s) and variant 6 (CD44v6), CD95/Fas, Fas-L, p53 and p-glycoprotein. All the parameters were analyzed for the influence on the occurrence of death and metastasis, plus patient overall survival (OS) and progression-free survival (PFS). The effect of sex, age, tumor location (distal femur or proximal tibia) and the combination with neoadjuvant chemotherapy was also assessed. Our results suggest that the presence of tumor-infiltrating CD4+ cells provides protection to OST patients, and that CD8+ cells have a significant impact on the patient's overall survival (OS) and progression-free survival (PFS), which is more evident in male patients. In addition, a strong association between tumor-infiltrating CD4+ cells and the presence of CD44s expression in tumor samples was observed. Analysis of TIL and tumor markers related to tumor biology could be useful to stratify patients and monitor the response to therapy, as well as to assist with the development of immunotherapy strategies to improve the effects of cytotoxic TIL to eradicate the tumor cells.

5.
Cancers (Basel) ; 13(15)2021 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-34359767

RESUMO

Soft-tissue sarcomas (STS) represent about 80% of sarcomas, and are a heterogeneous group of rare and malignant tumors. STS arise from mesenchymal tissues and can grow into structures such as adipose tissue, muscles, nervous tissue and blood vessels. Morphological evaluation has been the standard model for the diagnosis of sarcomas, and even in samples with similar characteristics, they present a diversity in cytogenetic and genetic sequence alterations, which further increases the diversity of sarcomas. This variety is one of the main challenges for the classification and understanding of STS patterns, as well as for their respective treatments, which further decreases patient survival (<5 years). Despite some studies, little is known about the immunological profile of STS. As for the immunological profile of STS in relation to NK cells, there is also a shortage of studies. Observations made in solid tumors show that the infiltration of NK cells in tumors is associated with a good prognosis of the disease. Notwithstanding the scarcity of studies to characterize NK cells, their receptors, and ligands in STS, it is noteworthy that the progression of these malignancies is associated with altered NK phenotypes. Despite the scarcity of information on the function of NK cells, their phenotypes and their regulatory pathways in STS, the findings of this study support the additional need to explore NK cell-based immunotherapy in STS further. Some clinical trials, very tentatively, are already underway. STS clinical trials are still the basis for adoptive NK-cell and cytokine-based therapy.

6.
Cancers (Basel) ; 13(15)2021 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-34359785

RESUMO

Soft Tissue Sarcomas (STS) are a heterogeneous and rare group of tumors. Immune cells, soluble factors, and immune checkpoints are key elements of the complex tumor microenvironment. Monitoring these elements could be used to predict the outcome of the disease, the response to therapy, and lead to the development of new immunotherapeutic approaches. Tumor-infiltrating B cells, Natural Killer (NK) cells, tumor-associated neutrophils (TANs), and dendritic cells (DCs) were associated with a better outcome. On the contrary, tumor-associated macrophages (TAMs) were correlated with a poor outcome. The evaluation of peripheral blood immunological status in STS could also be important and is still underexplored. The increased lymphocyte-to-monocyte ratio (LMR) and neutrophil-to-lymphocyte ratio (NLR), higher levels of monocytic myeloid-derived suppressor cells (M-MDSCs), and Tim-3 positive CD8 T cells appear to be negative prognostic markers. Meanwhile, NKG2D-positive CD8 T cells were correlated with a better outcome. Some soluble factors, such as cytokines, chemokines, growth factors, and immune checkpoints were associated with the prognosis. Similarly, the expression of immune-related genes in STS was also reviewed. Despite these efforts, only very little is known, and much research is still needed to clarify the role of the immune system in STS.

7.
BMC Immunol ; 22(1): 28, 2021 05 06.
Artigo em Inglês | MEDLINE | ID: mdl-33957866

RESUMO

BACKGROUND: Preterm birth (PTB) is one of the major causes of neonatal morbidity and mortality worldwide. It is commonly accepted that the act of giving birth is the final step in a proinflammatory signaling cascade, orchestrated by an intrauterine milieu coupled to hormonal cues. Consequently, the inflammatory process plays a pivotal role during the pathogenesis of human labor, both in term and preterm deliveries. The ability of innate lymphoid cells (ILCs) to act as pro-inflammatory mediators arose the interest to study their role in normal and pathological pregnancies. The aim of this work was to analyze the relative frequencies of ILCs subsets in pregnancy and the levels of IL-4, IL-17, IL-22, and IFN-γ as inflammatory mediators. Accordingly, we hypothesized that changes in the proportions of ILCs subpopulations could be related to preterm birth. METHODS: We analyzed 15 full-term delivery samples and six preterm delivery samples. In the full-term group (FTB) peripheral blood was taken during routine blood analysis, on 3 occasions: 1st, 2nd and 3rd trimester. After delivery, peripheral blood, cord blood and placenta were collected. In PTB group, peripheral blood samples were obtained on two occasions: before and 24 h after treatment with progesterone. We used flow cytometry to analyze ILCs in maternal peripheral blood, placenta, and cord blood samples. Maternal peripheral blood and cord blood samples were analyzed by enzyme-linked immunosorbent assay for IL-4, IL-17, IL-22, and IFN-γ plasma levels at the time of labor. RESULTS: We observed significantly increased relative frequencies of ILC2 and ILC3 in the decidua, as well as an increase of ILC2 in cord blood samples in PTB group, compared to FTB samples. We also found a decrease in IFN-γ in peripheral blood samples of the PTB group, suggesting a functional withdrawal. Additionally, IL-4, IL-17, IL-22 levels were similar in PTB and FTB groups, denoting a relevant role in mediating labor. CONCLUSION: Our results suggest that ILC2 and ILC3 play a role in PTB by mediating an inflammatory response. Further work is necessary to evaluate the importance of ILCs in the regulation of labor.


Assuntos
Linfócitos/imunologia , Nascimento Prematuro/imunologia , Células Th2/imunologia , Adulto , Citocinas/metabolismo , Feminino , Citometria de Fluxo , Humanos , Imunidade Inata , Recém-Nascido , Mediadores da Inflamação/metabolismo , Contagem de Linfócitos , Gravidez
8.
Front Immunol ; 11: 551707, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33329512

RESUMO

Innate lymphoid cells (ILCs) are a new set of cells considered to be a part of the innate immune system. ILCs are classified into five subsets (according to their transcription factors and cytokine profile) as natural killer cells (NK cells), group 1 ILCs, group 2 ILCs, group 3 ILCs, and lymphoid tissue inducers (LTi). Functionally, these cells resemble the T helper population but lack the expression of recombinant genes, which is essential for the formation of T cell receptors. In this work, the authors address the distinction between peripheral and decidual NK cells, highlighting their diversity in ILC biology and its relevance to human pregnancy. ILCs are effector cells that are important in promoting immunity, inflammation, and tissue repair. Recent studies have directed their attention to ILC actions in pregnancy. Dysregulation or expansion of pro-inflammatory ILC populations as well as abnormal tolerogenic responses may directly interfere with pregnancy, ultimately resulting in pregnancy loss or adverse outcomes. In this review, we characterize these cells, considering recent findings and addressing knowledge gaps in perinatal medicine in the context of ILC biology. Moreover, we discuss the relevance of these cells not only to the process of immune tolerance, but also in disease.


Assuntos
Citocinas/imunologia , Imunidade Inata , Células Matadoras Naturais/imunologia , Linfócitos T Auxiliares-Indutores/imunologia , Feminino , Humanos , Inflamação/imunologia , Inflamação/patologia , Células Matadoras Naturais/patologia , Gravidez
9.
Clin Immunol ; 218: 108521, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32619647

RESUMO

PURPOSE: To explore the cellular immune response of patients with resistant hypertension treated with renal denervation (RDN). METHODS AND RESULTS: Twenty-three patients were included and blood samples were obtained in six timings, pre and post procedure. Response was evaluated at six-months and one year and was observed in 69.6% and 82.6% of patients, respectively. Absolute values of HLA-DR+ double negative (DN) T cells were significantly lower in the group of 'responders' at one year, and interaction between the timings were found in three T cell subsets (T CD4, T CD8 and naïve T CD8 cells), with the 'responders' tending to present with lower absolute values and little inter-timing variation. CONCLUSIONS: 'Responders' significantly present with lower absolute values of activated DN T cells and have lower and more stable values of total T CD8+, CD4+, and naïve T CD8+ cells. These cell types may be able to predict response to RDN.


Assuntos
Hipertensão Renal/imunologia , Subpopulações de Linfócitos T/imunologia , Adulto , Idoso , Pressão Sanguínea , Ablação por Cateter , Citocinas/sangue , Denervação , Feminino , Artéria Femoral/cirurgia , Humanos , Hipertensão Renal/sangue , Hipertensão Renal/fisiopatologia , Hipertensão Renal/cirurgia , Rim/inervação , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
10.
Front Immunol ; 10: 2493, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31695700

RESUMO

Therapy with Tyrosine Kinase Inhibitors (TKI) aiming stable deep molecular response is the gold standard to treat Chronic Myeloid Leukemia (CML). NKT-like cells (CD3+CD56+) combine characteristics of T and NK cells. The physiopathological role of these cells remains unknown although the literature refers their association with inflammation, autoimmune diseases, and cancer. Since the information regarding the role of NKT-like cells in CML is rare, we aimed at the characterization of these cells in CML patients treated with TKIs. Peripheral blood NKT-like cells from 48 CML patients and 40 healthy donors were analyzed by multiparametric flow cytometry. Functional tests consisting of co-culture with leukemic target cells (K562 cell line) were used to measure degranulation and cytokine production. Our results revealed that NKT-like cells are decreased in treated CML patients, although they present increased expression of activation markers (CD69 and HLA-DR), increased degranulation (CD107a) and impaired IFN-γ production. Significantly alterations on the expression of tumor recognition (NCRs and NKp80), and immune regulation receptors (LAG-3, TIM-3, and CD137) by NKT-like cells were observed in CML patients. Second generation TKIs increased cell activation (CD69) and decreased expression of NKp44 and NKp80 by NKT-like cells from CML patients when compared to Imatinib. CML patients that achieved deep molecular response (MR4.5) presented downregulation of NKp44 and LAG-3. Further studies are needed to clarify the role of these cells as biomarkers of therapy response and also to evaluate their value for discrimination of better candidates for sustained treatment-free remission after TKI discontinuation.


Assuntos
Antígenos de Diferenciação/imunologia , Regulação Leucêmica da Expressão Gênica/efeitos dos fármacos , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Leucemia Mielogênica Crônica BCR-ABL Positiva/imunologia , Células T Matadoras Naturais/imunologia , Proteínas de Neoplasias/imunologia , Inibidores de Proteínas Quinases/administração & dosagem , Feminino , Regulação Leucêmica da Expressão Gênica/imunologia , Humanos , Células K562 , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , Masculino , Células T Matadoras Naturais/patologia
11.
J Clin Med ; 9(1)2019 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-31906092

RESUMO

Photodynamic therapy (PDT) relies on the administration of a photosensitizer (PS) that is activated, after a certain drug-to-light interval (DLI), by the irradiation of the target tumour with light of a specific wavelength absorbed by the PS. Typically, low light doses are insufficient to eradicate solid tumours and high fluence rates have been described as poorly immunogenic. However, previous work with mice bearing CT26 tumours demonstrated that vascular PDT with redaporfin, using a low light dose delivered at a high fluence rate, not only destroys the primary tumour but also reduces the formation of metastasis, thus suggesting anti-tumour immunity. This work characterizes immune responses triggered by redaporfin-PDT in mice bearing CT26 tumours. Our results demonstrate that vascular-PDT leads to a strong neutrophilia (2-24 h), systemic increase of IL-6 (24 h), increased percentage of CD4+ and CD8+ T cells producing IFN-γ or CD69+ (2-24 h) and increased CD4+/CD8+ T cell ratio (2-24 h). At the tumour bed, T cell tumour infiltration disappeared after PDT but reappeared with a much higher incidence one day later. In addition, it is shown that the therapeutic effect of redaporfin-PDT is highly dependent on neutrophils and CD8+ T cells but not on CD4+ T cells.

12.
Front Immunol ; 9: 2587, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30487792

RESUMO

Natural killer (NK) cells are a very important component of the innate immune response involved in the lysis of virus infected and tumor cells. Aging has a profound impact in the frequency, phenotype and function of NK cells. Chronic Myeloid Leukemia (CML) is caused by the BCR-ABL gene formation encoding aberrant oncoprotein tyrosine kinase. Treatment with tyrosine kinase inhibitors (TKIs) induces durable deep molecular response. The response to treatment and life expectancy is lower in older patients with chronic phase of CML than in younger patients. In this work we analyse NK cells from TKI-treated CML patients and healthy controls stratified according to age. We have analyzed the expression of NK receptors, activation markers, NK cell differentiation in CD56bright and CD56dim NK cell subsets and the expression of CD107a and IFN-γ in NK cells stimulated with K562. Whereas significant differences on the phenotype and function of NK cells were found between middle-aged (35-65 years old) and elderly (older than 65) healthy individuals, NK cells from TKI-treated CML patients do not show significant differences related with age in most parameters studied, indicating that age is not a limitation of the NK cell recovery after treatment with TKI. Our results also revealed differences in the expression of NK receptors, activation markers and functional assays in NK cells from TKI-treated CML patients compared with age-matched healthy controls. These results highlight the relevance of NK cells in TKI-treated patients and the need of an extensive analysis of the effect of aging on NK cell phenotype and function in these patients in order to define new NK-cell based strategies directed to control CML progression and achieve long-term disease remission after TKI cessation.


Assuntos
Fatores Etários , Envelhecimento/fisiologia , Antineoplásicos/uso terapêutico , Células Matadoras Naturais/imunologia , Leucemia Mielogênica Crônica BCR-ABL Positiva/imunologia , Inibidores de Proteínas Quinases/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Diferenciação Celular , Feminino , Genes abl/genética , Humanos , Células K562 , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Ativação Linfocitária , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
13.
Med Mycol ; 55(4): 358-367, 2017 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-27664993

RESUMO

Type 1 diabetes mellitus (T1D) is considered a risk factor associated with oral yeast infections. The aim of this study was to evaluate the yeast oral carriage (in saliva and mucosal surface) of children with T1D and potential relation with host factors, particularly the subset of CD4+ T cells. Yeasts were quantified and identified in stimulated saliva and in cheek mucosal swabs of 133 diabetic T1D and 72 healthy control subjects. Salivary lymphocytes were quantified using flow cytometry. The presence of yeasts in the oral cavity (60% of total patients) was not affected by diabetes, metabolic control, duration of the disease, salivary flow rate or saliva buffer capacity, by age, sex, place of residence, number of daily meals, consumption of sweets or frequency of tooth brushing. Candida albicans was the most prevalent yeast species, but a higher number of yeast species was isolated in nondiabetics. T1D children with HbA1c ≤ 7.5 (metabolically controlled) presented higher number of CD4+ T salivary subsets when compared with the other groups of children (non-diabetic and nonmetabolically controlled) and also presented the highest number of individuals without oral yeast colonization. In conclusion, T1D does not predisposes for increased oral yeast colonization and a higher number of salivary CD4+T cells seems to result in the absence of oral colonization by yeasts.


Assuntos
Causalidade , Diabetes Mellitus Tipo 1/complicações , Micoses/epidemiologia , Leveduras/isolamento & purificação , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Mucosa Bucal/microbiologia , Micoses/microbiologia , Prevalência , Medição de Risco , Saliva/microbiologia , Leveduras/classificação
14.
J Reprod Immunol ; 113: 22-6, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26517007

RESUMO

Progesterone acts as an immunosteroid by contributing to the establishment of a pregnancy-protective milieu. It seems that it is the responsibility of progesterone to evade the inflammatory events that lead to parturition. T regulatory lymphocytes (Treg cells) could further explain the inhibition of the inflammatory mechanisms that lead to labour through the rapid action of progesterone on this cell subset. We investigated Treg cells and the membrane progesterone receptor α (mPRα) in these immune cells with in relationship to human parturition. This pilot cohort study was conducted in a single-centre tertiary obstetrical unit with 20 normal pregnant women. Variation in the absolute and relative frequency of CD4(+) T cells, Treg cells, and of mPR(α+) Treg cells was calculated by flow cytometry on three occasions (second and third trimesters; delivery day). Our results show that during normal pregnancy there is a generalised increase in Treg cells and mPR(α+) Treg cells, from the second to the third trimesters (23.4% vs. 52.3% and 4.3% vs. 8.3%, respectively). On the contrary, on delivery day, compared with the values in the third trimester, there is a sudden decrease in both Treg cells (52.3% vs. 17.4%) and mPR(α+) Treg cells (8.3% vs. 6.1%). Our findings suggest that human labour may develop as a consequence of a decline in mPR(α+) Treg cells, which reduces progesterone anti-inflammatory action through Treg cells.


Assuntos
Membrana Celular/imunologia , Trabalho de Parto/imunologia , Gravidez/imunologia , Receptores de Progesterona/imunologia , Linfócitos T Reguladores/imunologia , Adulto , Feminino , Citometria de Fluxo , Humanos , Linfócitos T Reguladores/citologia
15.
Front Immunol ; 6: 658, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26793196

RESUMO

Leprosy is a chronic infectious disease caused by an obligate intracellular bacterium known as Mycobacterium leprae. Exposure to the bacillus is necessary, but this alone does not mean an individual will develop clinical symptoms of the disease. In recent years, several genes have been associated with leprosy and the innate immune response pathways converge on the main hypothesis that genes are involved in the susceptibility for the disease in two distinct steps: for leprosy per se and in the development of the different clinical forms. These genes participate in the sensing, main metabolic pathway of immune response activation and, subsequently, on the evolution of the disease into its clinical forms. The aim of this review is to highlight the role of innate immune response in the context of leprosy, stressing their participation in the signaling and targeting processes in response to bacillus infection and on the evolution to the clinical forms of the disease.

16.
PLoS One ; 9(3): e89939, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24643019

RESUMO

Leishmaniasis is a neglected tropical disease (NTDs), endemic in 88 countries, affecting more than 12 million people. The treatment consists in pentavalent antimony compounds, amphotericin B, pentamidine and miltefosine, among others. However, these current drugs are limited due to their toxicity, development of biological resistance, length of treatment and high cost. Thus, it is important to continue the search for new effective and less toxic treatments. The anti-Leishmania activity of sixteen semisynthetic lupane triterpenoids derivatives of betulin (BT01 to BT09) and betulinic acid (AB10 to AB16) were evaluated. Drug interactions between the active compounds and one current antileishmanial drug, miltefosine, were assessed using the fixed ratio isobologram method. In addition, effects on the cell cycle, apoptosis/necrosis events, morphology and DNA integrity were studied. The derivatives BT06 (3ß-Hydroxy-(20R)-lupan-29-oxo-28-yl-1H-imidazole-1-carboxylate) and AB13 (28-(1H-imidazole-1-yl)-3,28-dioxo-lup-1,20(29)-dien-2-yl-1H-imidazole-1-carboxylate) were found to be the most active, with IC50 values of 50.8 µM and 25.8 µM, respectively. Interactions between these two compounds and miltefosine were classified as synergistic, with the most effective association being between AB13 and miltefosine, where decreases of IC50 values to 6 µM were observed, similar to the miltefosine activity alone. AB13 induced significant morphological changes, while both derivatives produced anti-proliferative activity through cell cycle arrest at the G0/G1 phase. Neither of these derivatives induced significant apoptosis/necrosis, as indicated by phosphatidylserine externalization and DNA fragmentation assays. In addition, neither of the derivatives induced death in macrophage cell lines. Thus, they do not present any potential risk of toxicity for the host cells. This study has identified the betulin derivative BT06 and the betulinic acid derivative AB13 as promising molecules in the development of new alternative therapies for leishmaniasis, including those involving combined-therapy with miltefosine.


Assuntos
Antiprotozoários/farmacologia , Imidazóis/farmacologia , Leishmania infantum/efeitos dos fármacos , Estágios do Ciclo de Vida/efeitos dos fármacos , Fosforilcolina/análogos & derivados , Triterpenos/química , Triterpenos/farmacologia , Animais , Antiprotozoários/síntese química , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Sinergismo Farmacológico , Imidazóis/síntese química , Concentração Inibidora 50 , Leishmania infantum/crescimento & desenvolvimento , Estágios do Ciclo de Vida/fisiologia , Macrófagos/efeitos dos fármacos , Camundongos , Triterpenos Pentacíclicos , Fosforilcolina/farmacologia , Relação Estrutura-Atividade , Triterpenos/síntese química , Ácido Betulínico
17.
Acta Med Port ; 26(6): 676-82, 2013.
Artigo em Português | MEDLINE | ID: mdl-24388253

RESUMO

INTRODUCTION: The past decade has witnessed an increasing recognition that inflammatory mechanisms play a central role in the pathogenesis of atherosclerosis and its complications. Recently, attention was focused on the potential role of plasma markers of inflammation as risk predictors among those at risk for cardiovascular events. Of these potential markers, C-reactive protein (CRP), IL6, metalloproteinases, ICAM, VCAM and other molecules, have been extensively studied. On the other hand, to our knowledge, there are only a few studies on the role of inflammatory cells, like T and B lymphocytes in the atherosclerosis. MATERIAL AND METHODS: By flow cytometry analysis we have determined on dyslipidemic people and on a control group, the percentage of some peripheral inflammatory cells, like CD3+, CD4+, CD8+, CD19+, CD56+, CD56CD8+, DN, CD25+, CD26+, CD25CD3+, CD26CD3+, CD25CD26CD3+, CCR5+, CCR5CD3+, CCR5CD4+, HLADR+, HLADRCD4+, HLADRCD8h+, HLADRCD8low+, HLADRCD8+, CD95+, CD95CD95L+, CD3CD95+, CD3CD95L+, CD62L+, CD3CD62L+, CD69+, CD69CD3+ e CD69CD4+. RESULTS: In the present study we have particularly studied the percentage of CD4+, CD8+ and CD19+ cells. The CD4+ cells have been significantly reduced in the people with dyslipidemia. DISCUSSION: We do not know the peripheral numbers of the subtype Th1 and Th2, neither the percentage of CD4+CD25+ cells (regulatory T cells). We have not find any differences on the percentage from the CD8+ and CD19+ cells. CONCLUSIONS: In spite of the identified limitations resulting from the small-sized samples, it was possible to show a reduction of some molecules after application of acetylsalicylic acid.


Introdução: Os mecanismos imunológicos e inflamatórios têm um papel crucial no desenvolvimento da aterosclerose e na sua tradução clínica. São inúmeros os estudos que procuraram relacionar os mais diversos marcadores inflamatórios ­ leucócitos, proteína C reactiva, interleucinas, quimiocinas, moléculas de adesão, metaloproteinases, etc ­ com os factores de risco clássicos da aterosclerose, a formação da placa e os fenómenos clínicos. Não são tantos, que tenhamos conhecimento, os trabalhos que analisaram o comportamento das diversas células mononucleares na fisiopatologia da aterosclerose. Sendo os monócitos/macrófagos e os linfócitos células fundamentais no desencadear e posterior evolução desta doença vascular, procurámos determinar as percentagens das diversas populações celulares periféricas em indivíduos dislipidémicos e em normolipidémicos.Material e Métodos: Por citometria de fluxo, determinámos em indivíduos com dislipidemia e num grupo controlo, as concentrações no sangue periférico dos CD3+, CD4+, CD8+, CD19+, CD56+, CD56CD8+, DN, CD25+, CD26+, CD25CD3+, CD26CD3+, CD25CD26CD3+, CCR5+, CCR5CD3+, CCR5CD4+, HLADR+, HLADRCD4+, HLADRCD8h+, HLADRCD8low+, HLADRCD8+, CD95+, CD95CD95L+, CD3CD95+, CD3CD95L+, CD62L+, CD3CD62L+, CD69+, CD69CD3+ e CD69CD4+. Resultados: Embora na sua grande maioria não tenham sido encontradas diferenças significativas entre os dois grupos de participantes, verificaram-se em algumas populações celulares, resultados que nos mereceram alguns comentários. Neste artigo debruçámo-nos apenas sobre as populações positivas para os CD4, CD8 e CD19.Discussão: A menor concentração das células CD4+ na nossa população de dislipidémicos foi aparentemente inesperada devido ao relacionamento existente entre este tipo celular, os factores de risco e a aterosclerose. Não foram determinados os subtipos Th1 e Th2, nem a população de células reguladoras CD4+CD25+, que poderiam explicar a menor percentagem de células CD4+ nos nossos dislipidémicos. Relativamente às células CD8+ e CD19+, apresentaram percentagens sobreponíveis nos dois grupos de participantes.Conclusões: Apesar das limitações evidenciadas em resultado da reduzida dimensão das populações, foi possível demonstrar uma redução em algumas moléculas após aplicação de ácido acetilsalicílico.


Assuntos
Antígenos CD19 , Linfócitos T CD4-Positivos , Linfócitos T CD8-Positivos , Dislipidemias/sangue , Dislipidemias/imunologia , Subpopulações de Linfócitos T , Feminino , Humanos , Contagem de Linfócitos , Masculino , Pessoa de Meia-Idade
18.
Rev Port Pneumol ; 15(2): 261-93, 2009.
Artigo em Inglês, Português | MEDLINE | ID: mdl-19280073

RESUMO

UNLABELLED: Lung deep lymphatic drainage (LDLD) plays an important role in the removal of foreign materials from lungs being alveolar macrophages the first line of phagocytic defence with high affinity for pathogenic microorganisms. Bacillus subtilis is a well-known genome- decoded saprophyte of the human respiratory tract used in research and in the biotechnology industry. Lung deep lymphatic chains (LDLC) constitute one of the first sites of lung tumours' dissemination. In this work we intended to develop and validate a non-invasive method for assessing LDLC by nanoradioliposomes aerosolised modulated on the Bacillus subtilis spore wall. The final goal was to produce a nanoradioliposome formulation that can mimics the dynamics of preferential removal of spores by LDLD and present the ideal properties as a tracer for molecular imaging studies. Seven different liposomal formulations were tested, and the formulation-F demonstrated physicochemical and radiopharmaceutical properties that make it an ideal candidate as an in vivo probe for molecular imaging studies of the LDLC. Nanoradioliposomes of the formulation-F after labelling with 99mTc-HMPAO were administered as aerosols to 20 Sus scrofa. Hilar and interpulmonary communications were visualized in first 5 minutes post-inhalation, infradiaphragmatic chains between 10 and 20 minutes, the ganglia of the aortic chain at 20 minutes and those of the renal hilar region at 30 minutes. CONCLUSION: the proposed method enables visualization of deep lymphatic lung network and lymph nodes. Besides, this technique involving the modulation of nanoradioliposomes targeting specific organs or tissues may be an important tool for diagnostic or even for therapeutic purposes.


Assuntos
Lipossomos , Linfonodos/diagnóstico por imagem , Linfonodos/fisiologia , Linfa/diagnóstico por imagem , Compostos Radiofarmacêuticos , Tecnécio Tc 99m Exametazima , Animais , Pulmão , Masculino , Nanotecnologia , Cintilografia , Ratos , Ratos Wistar
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