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1.
J Immunol Res ; 2024: 7484490, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38455363

RESUMO

Macrophages are the immune cells of high-immunological plasticity, which can exert both pro- and anti-inflammatory activity, as well as repolarize their phenotype to the opposite or neutral one. In this regard, M2 macrophages of the tumor-associated stroma (TAS) are a promising therapeutic target in treating malignant neoplasms. Using FACS assay, we have estimated the CD11b+/Ly-6G+/Ly-6C+ fraction of macrophages from the peritoneum and TAS in intact healthy mice and those with developed Lewis carcinoma, both untreated and treated according to Karanahan technology in combination with group-specific macrophage activator (GcMAF-RF). As well, the pattern of pro- and anti-inflammatory cytokines mRNA expression in different groups of experimental and tumor-bearing animals was assessed. It was found that: (i) exposure of intact mice to GcMAF-RF results in the increased number of CD11b+/Ly-6C+ peritoneal macrophages and, at the same time, the expression pattern of cytokines in peritoneal macrophages switches from that characteristic of the mixed M1/M2 phenotype to that characteristic of the neutral M0 one; (ii) combination of Karanahan technology and GcMAF-RF treatment results in M0/M1 repolarization of TAS macrophages; (iii) in tumor-bearing mice, the response of peritoneal macrophages to such a treatment is associated with the induction of anti-inflammatory reaction, which is opposite to that in TAS macrophages.


Assuntos
Fatores Ativadores de Macrófagos , Macrófagos , Neoplasias , Proteína de Ligação a Vitamina D , Camundongos , Animais , Macrófagos Peritoneais/metabolismo , Citocinas/metabolismo , Neoplasias/patologia , Anti-Inflamatórios/metabolismo
2.
Int J Mol Sci ; 24(24)2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-38139225

RESUMO

Group-specific component macrophage-activating factor (GcMAF) is the vitamin D3-binding protein (DBP) deglycosylated at Thr420. The protein is believed to exhibit a wide range of therapeutic properties associated with the activation of macrophagal immunity. An original method for GcMAF production, DBP conversion to GcMAF, and the analysis of the activating potency of GcMAF was developed in this study. Data unveiling the molecular causes of macrophage activation were obtained. GcMAF was found to interact with three CLEC10A derivatives having molecular weights of 29 kDa, 63 kDa, and 65 kDa. GcMAF interacts with high-molecular-weight derivatives via Ca2+-dependent receptor engagement. Binding to the 65 kDa or 63 kDa derivative determines the pro- and anti-inflammatory direction of cytokine mRNA expression: 65 kDa-pro-inflammatory (TNF-α, IL-1ß) and 63 kDa-anti-inflammatory (TGF-ß, IL-10). No Ca2+ ions are required for the interaction with the canonical 29 kDa CLEC10A. Both forms, DBP protein and GcMAF, bind to the 29 kDa CLEC10A. This interaction is characterized by the stochastic mRNA synthesis of the analyzed cytokines. Ex vivo experiments have demonstrated that when there is an excess of GcMAF ligand, CLEC10A forms aggregate, and the mRNA synthesis of analyzed cytokines is inhibited. A schematic diagram of the presumable mechanism of interaction between the CLEC10A derivatives and GcMAF is provided. The principles and elements of standardizing the GcMAF preparation are elaborated.


Assuntos
Fatores Ativadores de Macrófagos , Macrófagos , Proteína de Ligação a Vitamina D , Anti-Inflamatórios , Fatores Ativadores de Macrófagos/metabolismo , Macrófagos/metabolismo , RNA Mensageiro , Humanos , Proteína de Ligação a Vitamina D/metabolismo
3.
Molecules ; 28(4)2023 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-36838558

RESUMO

O-linked α-N-acetylgalactosamine (α-GalNAc) in the Gc protein is essential for macrophage activation; thus, the GalNAc-attached form of Gc protein is called Gc macrophage activating factor (GcMAF). O-linked glycans in Gc proteins from human plasma mainly consist of trisaccharides. GcMAF is produced when glycans on the Gc protein are hydrolyzed by α-Sia-ase and ß-Gal-ase, leaving an α-GalNAc. Upon hydrolysis of α-GalNAc present on GcMAF, the protein loses the macrophage-activating effect. In contrast, our synthesized pyrrolidine-type iminocyclitol possessed strong in vitro α-GalNAc-ase inhibitory activity. In this study, we examined the protective effects of iminocyclitol against GcMAF via inhibition of α-GalNAc-ase activity. Detailed mass spectrometric analyses revealed the protective effect of the inhibitor on GcMAF. Furthermore, structural information regarding the glycosylation site and glycan structure was obtained using tandem mass spectrometric (MS/MS) analysis of the glycosylated peptides after tryptic digestion.


Assuntos
Polissacarídeos , Espectrometria de Massas em Tandem , Humanos , Polissacarídeos/química , Fatores Ativadores de Macrófagos/química , Fatores Ativadores de Macrófagos/metabolismo , Fatores Ativadores de Macrófagos/farmacologia , Glicosídeo Hidrolases
4.
Int J Mol Sci ; 23(15)2022 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-35897653

RESUMO

The main problem related to the studies focusing on group-specific component protein-derived macrophage-activating factor (GcMAF) is the lack of clarity about changes occurring in different types of macrophages and related changes in their properties under the effect of GcMAF in various clinical conditions. We analyzed the antitumor therapeutic properties of GcMAF in a Lewis carcinoma model in two clinical conditions: untreated tumor lesion and tumor resorption after exposure to Karanahan therapy. GcMAF is formed during site-specific deglycosylation of vitamin D3 binding protein (DBP). DBP was obtained from the blood of healthy donors using affinity chromatography on a column with covalently bound actin. GcMAF-related factor (GcMAF-RF) was converted in a mixture with induced lymphocytes through the cellular enzymatic pathway. The obtained GcMAF-RF activates murine peritoneal macrophages (p < 0.05), induces functional properties of dendritic cells (p < 0.05) and promotes in vitro polarization of human M0 macrophages to M1 macrophages (p < 0.01). Treatment of whole blood cells with GcMAF-RF results in active production of both pro- and anti-inflammatory cytokines. It is shown that macrophage activation by GcMAF-RF is inhibited by tumor-secreted factors. In order to identify the specific antitumor effect of GcMAF-RF-activated macrophages, an approach to primary reduction of humoral suppressor activity of the tumor using the Karanahan therapy followed by macrophage activation in the tumor-associated stroma (TAS) was proposed. A prominent additive effect of GcMAF-RF, which enhances the primary immune response activation by the Karanahan therapy, was shown in the model of murine Lewis carcinoma. Inhibition of the suppressive effect of TAS is the main condition required for the manifestation of the antitumor effect of GcMAF-RF. When properly applied in combination with any chemotherapy, significantly reducing the humoral immune response at the advanced tumor site, GcMAF-RF is a promising antitumor therapeutic agent that additively destroys the pro-tumor properties of macrophages of the tumor stroma.


Assuntos
Carcinoma , Fatores Ativadores de Macrófagos , Proteína de Ligação a Vitamina D , Animais , Proteínas Sanguíneas/metabolismo , Carcinoma/tratamento farmacológico , Humanos , Ativação de Macrófagos , Fatores Ativadores de Macrófagos/metabolismo , Camundongos , Proteína de Ligação a Vitamina D/metabolismo
5.
J Reprod Immunol ; 153: 103660, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35843133

RESUMO

Periparturient dairy cows and their newborn calves are highly prone to health complications. Enhancing the innate immune system of these animals is essential to mitigate the transition period stress and promote their health. Macrophage activating factor (MAF) possess immunomodulatory properties and is believed to enhance immune response. In the present study, the impact of different concentrations (10, 50, 100 ng) of MAF on the phagocytic activity (PA) of murine and bovine phagocytoses was explored. MAF synthesized from IgA of cow colostrum was studied for its effect on the phagocytic index (PI) of cow colostrum macrophages (Mφ) and blood neutrophils (sick and healthy calves) under in vitro conditions. Besides, the impact of MAF on the PI of peritoneal Mφ of healthy and immunocompromised mice was studied. PI of healthy Mφ (mice peritoneal and cow colostrum) and healthy neutrophils (blood calf) increased significantly (P < 0.05) after MAF supplementation. MAF also significantly (P < 0.05) increased the PI of neutrophils and Mφ obtained from sick calf and immunocompromised mice, respectively. Results indicate that colostrum MAF can be used as a potential immune modulator to promote immunity and fight infections in dairy animals.


Assuntos
Colostro , Fagócitos , Animais , Bovinos , Feminino , Imunoglobulina A , Fatores Ativadores de Macrófagos , Macrófagos , Camundongos , Gravidez
6.
Cancer Treat Res Commun ; 31: 100537, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35217488

RESUMO

This overview describes the research of Nobutu Yamamoto (Philadelphia) concerning immunotherapy with GcMAF for patients with cancer and for patients infected with pathogenic envelope viruses. GcMAF (Group-specific component Macrophage-Activating Factor) is a mammalian protein with an incredible potency to directly activate macrophages. Since the late 1980s Yamamoto's investigations were published in numerous journals but in order to understand the details of his research, a minute survey of many of his patents was required. But even then, regrettably, a precise description of his experiments was sometimes lacking. This overview tries to summarize all of Yamamoto's research on GcMAF, as well as some selected more recent papers from other investigators, who tried to verify and/or reproduce Yamamoto's reports. In my opinion the most important result of the GcMAF research deserves widespread renewed attention: human GcMAF injections (100 ng per week, intramuscular or intravenous) can help to cure patients with a great variety of cancers as well as patients infected with pathogenic envelope viruses like the human immunodeficiency virus 1 (HIV-1), influenza, measles and rubella (and maybe also SARS-CoV-2). From Yamamoto's data it can be calculated that GcMAF is a near-stoichiometric activator of macrophages. Yamamoto monitored the progress of his immunotherapy via the serum level of an enzyme called nagalase (α-N-acetylgalactosaminidase activity at pH 6). I have extensively discussed the properties and potential catalytic site of this enzyme activity in an Appendix entitled: "Search for the potential active site of the latent α-N-acetylgalactosaminidase activity in the glycoproteins of some envelope viruses".


Assuntos
Imunoterapia , Fatores Ativadores de Macrófagos , Neoplasias , Proteína de Ligação a Vitamina D , Animais , Humanos , Fatores Ativadores de Macrófagos/uso terapêutico , Neoplasias/imunologia , Neoplasias/terapia , Neoplasias/virologia , Viroses/tratamento farmacológico , Viroses/imunologia , Viroses/virologia , Proteína de Ligação a Vitamina D/uso terapêutico , alfa-N-Acetilgalactosaminidase/imunologia
7.
Anticancer Res ; 41(8): 4089-4092, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34281879

RESUMO

BACKGROUND/AIM: Serum-derived macrophage activating factor (serum-MAF) is expected to have adjuvant effects through rapid phagocytic activation, which depends on F-actin accumulation in multi-layered membrane ruffles induced within 5 min after serum-MAF addition. This study aimed to elucidate the importance of annexin A2, which is a multifunctional Ca2+-binding protein related to cytoskeletal membrane dynamics, in serum-MAF signalling. MATERIALS AND METHODS: Annexin A2 and F-actin localizations were analyzed via immunostaining and confocal microscopy. Using EGTA as chelator, the role of Ca2+ in serum-MAF signalling was examined. RESULTS: Annexin A2 was found to translocate from the cytosol to the cell cortex within 30 s of serum-MAF stimulation. Ca2+ chelation inhibited the translocation of annexin A2, frill-like structure formation, and phagocytic activation by serum-MAF. CONCLUSION: Annexin A2 and Ca2+ were responsible for the rapid phagocytic activation by serum-MAF. This study provides an understanding of phagocytic activation in macrophages, which could be beneficial for cancer immunotherapy.


Assuntos
Anexina A2/metabolismo , Ativação de Macrófagos , Fatores Ativadores de Macrófagos/sangue , Macrófagos/fisiologia , Actinas/metabolismo , Humanos , Fagocitose , Células THP-1
9.
J Hepatol ; 74(5): 1145-1154, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33276030

RESUMO

BACKGROUND & AIMS: While cholangiocarcinomas (CCAs) commonly express programmed cell death 1 (PD-1) and its ligand (PD-L1), they respond poorly to immune checkpoint inhibitors (ICIs). We aimed to determine whether stimulating antigen-presenting cells, including macrophages and dendritic cells, using a CD40 agonist could improve this response. METHODS: We compared treatment responses in subcutaneous, orthotopic, and 2 plasmid-based murine intrahepatic CCA (iCCA) models. Mice were treated for 4 weeks with weekly IgG control, a CD40 agonistic antibody, anti-PD-1, or the combination of both (anti-CD40/PD-1). Flow cytometric (FACS) analysis of lymphocytes and myeloid cell populations (including activation status) was performed. We used dendritic cell knockout mice, and macrophage, CD4+ and CD8+ T cell depletion models to identify effector cells. Anti-CD40/PD-1 was combined with chemotherapy (gemcitabine/cisplatin) to test for improved therapeutic efficacy. RESULTS: In all 4 models, anti-PD-1 alone was minimally efficacious. Mice exhibited a moderate response to CD40 agonist monotherapy. Combination anti-CD40/PD-1 therapy led to a significantly greater reduction in tumor burden. FACS demonstrated increased number and activation of CD4+ and CD8+ T cells, natural killer cells, and myeloid cells in tumor and non-tumor liver tissue of tumor-bearing mice treated with anti-CD40/PD-1. Depletion of macrophages, dendritic cells, CD4+ T cells, or CD8+ T cells abrogated treatment efficacy. Combining anti-CD40/PD-1 with gemcitabine/cisplatin resulted in a significant survival benefit compared to gemcitabine/cisplatin alone. CONCLUSION: CD40-mediated activation of macrophages and dendritic cells in iCCA significantly enhances response to anti-PD-1 therapy. This regimen may enhance the efficacy of first-line chemotherapy. LAY SUMMARY: Checkpoint inhibition, a common form of immune therapy, is generally ineffective for the treatment of cholangiocarcinoma. These tumors suppress the infiltration and function of surrounding immune cells. Stimulating immune cells such as macrophages and dendritic cells via the CD40 receptor activates downstream immune cells and enhances the response to checkpoint inhibitors.


Assuntos
Antígenos CD40/agonistas , Colangiocarcinoma , Inibidores de Checkpoint Imunológico/farmacologia , Neoplasias Hepáticas , Ativação de Macrófagos/imunologia , Microambiente Tumoral , Animais , Antimetabólitos Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Colangiocarcinoma/imunologia , Colangiocarcinoma/patologia , Cisplatino/farmacologia , Células Dendríticas/imunologia , Desoxicitidina/análogos & derivados , Desoxicitidina/farmacologia , Sensibilidade Colateral a Medicamentos , Neoplasias Hepáticas/imunologia , Neoplasias Hepáticas/patologia , Linfócitos do Interstício Tumoral/efeitos dos fármacos , Fatores Ativadores de Macrófagos/imunologia , Camundongos , Camundongos Knockout , Microambiente Tumoral/efeitos dos fármacos , Microambiente Tumoral/imunologia , Gencitabina
11.
Sci Rep ; 10(1): 19122, 2020 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-33154460

RESUMO

Human group-specific component protein (Gc protein) is a multifunctional serum protein which has three common allelic variants, Gc1F, Gc1S and Gc2 in humans. Gc1 contains an O-linked trisaccharide [sialic acid-galactose-N-acetylgalactosamine (GalNAc)] on the threonine420 (Thr420) residue and can be converted to a potent macrophage activating factor (GcMAF) by selective removal of sialic acid and galactose, leaving GalNAc at Thr420. In contrast, Gc2 is not glycosylated. GcMAF is considered a promising candidate for immunotherapy and antiangiogenic therapy of cancers and has attracted great interest, but it remains difficult to compare findings among research groups because different procedures have been used to prepare GcMAF. Here, we present a simple, practical method to prepare high-quality GcMAF by overexpressing Gc-protein in a serum-free suspension culture of ExpiCHO-S cells, without the need for a de-glycosylation step. We believe this protocol is suitable for large-scale production of GcMAF for functional analysis and clinical testing.


Assuntos
Fatores Ativadores de Macrófagos/síntese química , Proteína de Ligação a Vitamina D/síntese química , Animais , Células CHO , Proliferação de Células/efeitos dos fármacos , Cricetulus , Humanos , Fatores Ativadores de Macrófagos/farmacologia , Fagocitose/efeitos dos fármacos , Proteína de Ligação a Vitamina D/farmacologia
12.
Protein Expr Purif ; 175: 105714, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32738434

RESUMO

Cancer immunotherapy has recently attracted attention as an approach for cancer treatment through the activation of the immune system. Group-specific component (Gc) protein is a precursor for macrophage activating factor (GcMAF), which has a promising immunomodulatory effect on the suppression of tumor growth and angiogenesis. In this study, we successfully purified Gc protein from human serum using anion-exchange chromatography combined with affinity chromatography using a 25-OH-D3-immobilized column. The purity of Gc protein reached 95.0% after anion-exchange chromatography. The known allelic variants of Gc protein are classified into three subtypes-Gc1F, Gc1S and Gc2. The fragment sequence of residues 412-424 determined according to their MS/MS spectra is available to evaluate the subtypes of Gc protein. The data showed that the Gc protein purified in this study consisted of the Gc1F and Gc2 subtypes. Our method improved the purity of Gc protein, which was not affected by the treatment to convert it into GcMAF using ß-galactosidase- or neuraminidase-immobilized resin, and will be useful for biological studies and/or advanced clinical uses of GcMAF, such as cancer immunotherapy.


Assuntos
Cromatografia de Afinidade , Fatores Ativadores de Macrófagos , Proteína de Ligação a Vitamina D , Humanos , Fatores Ativadores de Macrófagos/química , Fatores Ativadores de Macrófagos/isolamento & purificação , Proteína de Ligação a Vitamina D/química , Proteína de Ligação a Vitamina D/isolamento & purificação
13.
Anticancer Res ; 40(8): 4707-4710, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32727796

RESUMO

BACKGROUND/AIM: Serum-derived macrophage activating factor (serum-MAF) can rapidly activate macrophage phagocytic activity by inducing characteristic membrane ruffles designated as Frill-like structures. Serum-MAF contains γ-globulin, an activator of phagocytosis. This study examined whether serum-MAF and γ-globulin activate macrophages similarly. MATERIALS AND METHODS: Morphological changes in macrophages were observed by time-lapse imaging and the efficiency of engulfment was analysed quantitatively. Immunological staining of talin-1 and a calpain inhibitor were performed. RESULTS: The engulfment efficiency of serum-MAF- and γ-globulin-activated macrophages was significantly different. Talin-1 showed weak co-localisation with the Frill-like structures. Treatment with a calpain inhibitor similarly down-regulated phagocytosis irrespective of the activation factor. CONCLUSION: There was a difference between macrophage activation mechanisms by γ-globulin and serum-MAF. Talin may slightly contribute to serum-MAF activation. It is possible to distinguish between the calpain-dependent fundamental 'mechanism of phagocytosis' and the activating factor-dependent rapid 'activation mechanism'.


Assuntos
Ativação de Macrófagos/efeitos dos fármacos , Fatores Ativadores de Macrófagos/farmacologia , Macrófagos/efeitos dos fármacos , gama-Globulinas/farmacologia , Calpaína/farmacologia , Linhagem Celular , Regulação para Baixo/efeitos dos fármacos , Humanos , Fagocitose/efeitos dos fármacos , Células THP-1
15.
Immunol Cell Biol ; 97(2): 203-217, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30298952

RESUMO

Although recent evidence has shown that IL-6 is involved in enhanced alternative activation of macrophages toward a profibrotic phenotype, the mechanisms leading to their increased secretory capacity are not fully understood. Here, we investigated the effect of IL-6 on endoplasmic reticulum (ER) expansion and alternative activation of macrophages in vitro. An essential mediator in this ER expansion process is the IRE1 pathway, which possesses a kinase and endoribonuclease domain to cleave XBP1 into a spliced bioactive molecule. To investigate the IRE1-XBP1 expansion pathway, IL-4/IL-13 and IL-4/IL-13/IL-6-mediated alternative programming of murine bone marrow-derived and human THP1 macrophages were assessed by arginase activity in cell lysates, CD206 and arginase-1 expression by flow cytometry, and secreted CCL18 by ELISA, respectively. Ultrastructural intracellular morphology and ER biogenesis were examined by transmission electron microscopy and immunofluorescence. Transcription profiling of 128 genes were assessed by NanoString and Pharmacological inhibition of the IRE1-XBP1 arm was achieved using STF-083010 and was verified by RT-PCR. The addition of IL-6 to the conventional alternative programming cocktail IL-4/IL-13 resulted in increased ER and mitochondrial expansion, profibrotic profiles and unfolded protein response-mediated induction of molecular chaperones. IRE1-XBP1 inhibition substantially reduced the IL-6-mediated hyperpolarization and normalized the above effects. In conclusion, the addition of IL-6 enhances ER expansion and the profibrotic capacity of IL-4/IL-13-mediated activation of macrophages. Therapeutic strategies targeting IL-6 or the IRE1-XBP1 axis may be beneficial to prevent the profibrotic capacity of macrophages.


Assuntos
Retículo Endoplasmático , Endorribonucleases/metabolismo , Interleucina-3/metabolismo , Interleucina-4/metabolismo , Interleucina-6/metabolismo , Fatores Ativadores de Macrófagos/metabolismo , Macrófagos/imunologia , Macrófagos/ultraestrutura , Proteínas Serina-Treonina Quinases/metabolismo , Animais , Retículo Endoplasmático/efeitos dos fármacos , Retículo Endoplasmático/fisiologia , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Estresse do Retículo Endoplasmático/imunologia , Humanos , Interleucina-4/farmacologia , Interleucina-6/farmacologia , Ativação de Macrófagos , Camundongos , Camundongos Endogâmicos C57BL , Transdução de Sinais/efeitos dos fármacos , Células THP-1
16.
Anticancer Res ; 38(7): 4295-4298, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29970564

RESUMO

BACKGROUND/AIM: Serum-derived macrophage activating factor (serum MAF) is known to increase the phagocytic activity of macrophages and potentially plays a role in activating cancer immunity. In order to reveal the contributing factors for phagocytic activation, the migratory activity and the efficiency of engulfment was analyzed. MATERIALS AND METHODS: THP-1 macrophages were induced by 12-O-tetradecanoyl-13-acetate (TPA). The migratory activity and efficiency of engulfment were analyzed by time-lapse imaging and suspension assay, respectively. RESULTS: While the distance of migration did not change before and after activation with serum MAF, the efficiency of beads internalisation was significantly increased. CONCLUSION: Phagocytic activation of serum-MAF-treated macrophages was caused by increasing the efficiency of engulfment. This study contributes to the knowledge about the activation of the immune system through phagocytic activation of macrophages.


Assuntos
Ativação de Macrófagos/efeitos dos fármacos , Ativação de Macrófagos/imunologia , Fatores Ativadores de Macrófagos/farmacologia , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Fagocitose/fisiologia , Linhagem Celular , Humanos , Ativação de Macrófagos/fisiologia
18.
Mar Drugs ; 16(5)2018 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-29748462

RESUMO

α-N-acetylgalactosaminidase (EC 3.2.1.49) (alpha-NaGalase) catalyzes the hydrolysis of N-acetamido-2-deoxy-α-d-galactoside residues from non-reducing ends of various complex carbohydrates and glycoconjugates. It is known that human cancer cells express an alpha-NaGalase, which accumulates in the blood plasma of patients. The enzyme deglycosylates the Gc protein-derived macrophage activating factor (GcMAF) and inhibits macrophage activity acting as an immunosuppressor. The high specific activity 0.033 ± 0.002 μmol mg−1 min−1 of the enzyme was found in human colon carcinoma cells DLD-1. The alpha-NaGalase of DLD-1 cells was isolated and biochemical characterized. The enzyme exhibits maximum activity at pH 5.2 and temperature 55 °C. The Km is 2.15 mM, Vmax⁻0.021 μmol min−1 mL−1, kcat⁻1.55 min−1 and kcat/Km⁻0.72 min−1 mM−1 at 37 °C, pH 5.2. The effects of fucoidan from the brown alga Fucus evanescence on the activity of alpha-NaGalase in human colon carcinoma DLD-1 cells and on the biosynthesis of this enzyme were investigated. It was shown that fucoidan did not inhibit free alpha-NaGalase, however, it reduced the expression of the enzyme in the DLD-1 cells at IC50 73 ± 4 μg mL−1.


Assuntos
Carcinoma/metabolismo , Neoplasias do Colo/metabolismo , Fucus/química , Polissacarídeos/farmacologia , alfa-N-Acetilgalactosaminidase/metabolismo , Linhagem Celular Tumoral , Colo/metabolismo , Células HT29 , Humanos , Fatores Ativadores de Macrófagos/metabolismo , Proteína de Ligação a Vitamina D/metabolismo
19.
J Womens Health (Larchmt) ; 26(8): 878-885, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28661774

RESUMO

BACKGROUND: Women with physical disabilities increasingly aspire to become pregnant and bear children. Limited information about the potential interaction of their disabling conditions with pregnancy and childbirth exists to guide these women and their clinicians. MATERIALS AND METHODS: The interview guide was created with questions on topics such as pregnancy complications and secondary conditions, the impact of prior surgeries, experiences with pain relief during labor, and the impact on women's independence and participation in life activities. Interviews were conducted by telephone with 25 women with physical disabilities. They were subsequently transcribed verbatim and analyzed by using Atlas TI. RESULTS: Women generally reported a relatively modest impact of disabling conditions on their pregnancies. Most women were satisfied with the mode of delivery, but they experienced challenges during the labor and delivery process. The women found that careful advanced planning was helpful in managing the impact of their disabling conditions. The involvement of clinicians with disability-related expertise was, in some cases, another factor that contributed to a positive outcome. CONCLUSIONS: The importance of advanced planning and the utility of involving clinicians with disability-related expertise suggest that the use of integrated, interdisciplinary team approaches could promote quality care by facilitating improved planning and management. Additional clinical research is needed to provide women and their clinicians with more information on potential complications and options for labor and delivery.


Assuntos
Parto Obstétrico/métodos , Pessoas com Deficiência , Conhecimentos, Atitudes e Prática em Saúde , Parto , Gravidez de Alto Risco , Cuidado Pré-Natal/métodos , Adulto , Feminino , Humanos , Entrevistas como Assunto , Fatores Ativadores de Macrófagos , Mães , Gravidez , Complicações na Gravidez/prevenção & controle , Precursores de Proteínas , Pesquisa Qualitativa
20.
Am J Respir Crit Care Med ; 196(10): 1275-1286, 2017 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-28598224

RESUMO

RATIONALE: Acute respiratory distress syndrome (ARDS) remains a major cause of respiratory failure in critically ill patients. Mesenchymal stromal cells (MSCs) are a promising candidate for a cell-based therapy. However, the mechanisms of MSCs' effects in ARDS are not well understood. In this study, we focused on the paracrine effect of MSCs on macrophage polarization and the role of extracellular vesicle (EV)-mediated mitochondrial transfer. OBJECTIVES: To determine the effects of human MSCs on macrophage function in the ARDS environment and to elucidate the mechanisms of these effects. METHODS: Human monocyte-derived macrophages (MDMs) were studied in noncontact coculture with human MSCs when stimulated with LPS or bronchoalveolar lavage fluid (BALF) from patients with ARDS. Murine alveolar macrophages (AMs) were cultured ex vivo with/without human MSC-derived EVs before adoptive transfer to LPS-injured mice. MEASUREMENTS AND MAIN RESULTS: MSCs suppressed cytokine production, increased M2 macrophage marker expression, and augmented phagocytic capacity of human MDMs stimulated with LPS or ARDS BALF. These effects were partially mediated by CD44-expressing EVs. Adoptive transfer of AMs pretreated with MSC-derived EVs reduced inflammation and lung injury in LPS-injured mice. Inhibition of oxidative phosphorylation in MDMs prevented the modulatory effects of MSCs. Generating dysfunctional mitochondria in MSCs using rhodamine 6G pretreatment also abrogated these effects. CONCLUSIONS: In the ARDS environment, MSCs promote an antiinflammatory and highly phagocytic macrophage phenotype through EV-mediated mitochondrial transfer. MSC-induced changes in macrophage phenotype critically depend on enhancement of macrophage oxidative phosphorylation. AMs treated with MSC-derived EVs ameliorate lung injury in vivo.


Assuntos
Lesão Pulmonar Aguda/fisiopatologia , Lesão Pulmonar Aguda/terapia , Vesículas Extracelulares/fisiologia , Fatores Ativadores de Macrófagos/uso terapêutico , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/fisiologia , Mitocôndrias/fisiologia , Animais , Feminino , Humanos , Masculino , Camundongos , Modelos Animais
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