961 resultados para GRAFT-VS-HOST DISEASE
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Purpose: To analyze the influence of thermal partial punctal occlusion on the ocular surface of dry eye related to Sjogren syndrome. Material and Methods: Thirty-seven eyes of 19 patients (3 male and 16 female; 49.11 +/- 14.33 years old) with keratoconjunctivitis sicca were enrolled in this study. Superior and inferior partial occlusion were performed in both eyes under topical anesthesia using thermal cautery with a sterile tip to obtain lacrimal punctum smaller than 0.5 mm. Schirmer I, break-up-time, diameter of lacrimal puncta, corneal fluorescein, and rose Bengal staining scores were analyzed before and after 24 weeks and after 24 months of the procedure. All measurements were performed under controlled climate. Results: The average lacrimal punctum diameter before the procedure was 0.65 +/- 0.134 mm. All lacrimal puncta were successfully reduced to less than 0.5 mm after 4 weeks of the procedure. The average Schirmer I test values improved statistically after 24 weeks and maintained stable after 24 months. Average break-up-time, rose Bengal, and fluorescein staining score values improved statistically after 24 weeks and improved even more after 24 months. Average Schirmer I test, break-up-time, rose Bengal, and fluorescein staining scores showed significant improvement (p < 0.0001) after 24 months of partial thermal punctal occlusion. Conclusion: Our study showed that reducing the punctum diameter to 0.5 mm can improve vital staining scores, break-up-time, and Schirmer I test in dry eye related to Sjogren syndrome.
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Dendritic cells belong to a family of antigen-presenting cells that are localized at the entry sites, such as skin and mucosa. Dendritic cells are related to immune surveillance function. The role of Langerhans cells in the pathogenesis of skin infectious diseases is well studied; however, there are few articles addressing involvement of factor XIIIa-positive dermal dendrocytes (FXIIIa+ DD) in such processes. FXIIIa+ DDs are bone marrow-monocytic lineage-derived cells and members of the skin immune system. Due to their immune phenotype and functional characteristics, they are considered complementary cells to Langerhans cells in the process of antigen presentation and inducing immune response. To verify the interaction between FXIIIa+ DD and Leishmania amastigotes, 22 biopsies of American tegumentary leishmaniasis (ATL) skin lesions were subjected to double staining technique with anti-factor XIIIa and anti-Leishmania antibodies. FXIIIa+ DDs were hypertrophic and abundant in the cutaneous reaction of ATL. FXIIIa+ DDs harboring parasites were observed in I I of 22 skin biopsies. The data obtained suggest that FXIIIa+ DD plays a role in the pathogenesis of ATL skin lesion as host cell, immune effector, and/or antigen-presenting cell.
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The local and systemic treatment of tumors can cause changes in the skin, mucous membranes, hair and nails. Accurate diagnosis and appropriate treatment of side effects require knowledge about the patterns of the most common adverse reactions to drugs the patient may be using. The dermatologist must be familiar with the manifestations of certain soft tissue neoplasms, as well as with the adverse mucocutaneous forms of cancer treatment.
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Cell adhesion molecules such as intercellular adhesion molecule-1 (ICAM-1) and platelet-endothelial cell adhesion molecule-1 (PECAM-1) play an important role in glioma invasion and angiogenesis. The aim of this study was to investigate whether specific genetic polymorphisms of ICAM-1 and PECAM-1 could be associated with glioma development and progression. Single-nucleotide polymorphism in codon 469 of ICAM-1 and codon 125 of PECAM-1 were examined in 158 patients with astrocytomas and 162 controls using polymerase chain reaction and restriction enzyme analysis. The distribution of PECAM-1 polymorphic genotypes in astrocytomas did not show any significant difference. However, a specific ICAM-1 genotype (G/G, corresponding to Lys469Glu) exhibited higher frequency in grade II astrocytomas compared to controls, grade III, and grade IV astrocytomas; suggesting that this polymorphism could be involved in the development of grade II astrocytomas.
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Mesenchymal stromal cells (MSCs) suppress T cell responses through mechanisms not completely understood. Adenosine is a strong immunosuppressant that acts mainly through its receptor A(2a) (ADORA2A). Extracellular adenosine levels are a net result of its production (mediated by CD39 and CD73), and of its conversion into inosine by Adenosine Deaminase (ADA). Here we investigated the involvement of ADO in the immunomodulation promoted by MSCs. Human T lymphocytes were activated and cultured with or without MSCs. Compared to lymphocytes cultured without MSCs, co-cultured lymphocytes were suppressed and expressed higher levels of ADORA2A and lower levels of ADA. In co-cultures, the percentage of MSCs expressing CD39, and of T lymphocytes expressing CD73, increased significantly and adenosine levels were higher. Incubation of MSCs with media conditioned by activated T lymphocytes induced the production of adenosine to levels similar to those observed in co-cultures, indicating that adenosine production was mainly derived from MSCs. Finally, blocking ADORA2A signaling raised lymphocyte proliferation significantly. Our results suggest that some of the immunomodulatory properties of MSCs may, in part, be mediated through the modulation of components related to adenosine signaling. These findings may open new avenues for the development of new treatments for GVHD and other inflammatory diseases. (C) 2011 Elsevier B.V. All rights reserved.
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Blood irradiation can be performed using a dedicated blood irradiator or a teletherapy unit. A thermal device providing appropriate storage conditions during blood components irradiation with a teletherapy unit has been recently proposed. However, the most appropriated volume of the thermal device was not indicated. The goal of this study was to indicate the most appropriated blood volume for irradiation using a teletherapy unit in order to minimize both the dose heterogeneity in the volume and the blood irradiation time using these equipments. Theoretical and experimental methods were used to study the dose distribution in the blood volume irradiated using a linear accelerator and a cobalt-60 therapy machine. The calculation of absorbed doses in the middle plane of cylindrical acrylic volumes was accomplished by a treatment planning system. Experimentally, we also used cylindrical acrylic phantoms and thermoluminescent dosimeters to confirm the calculated doses. The data obtained were represented by isodose curves. We observed that an irradiation volume should have a height of 28 cm and a diameter of 28 cm and a height of 35 cm and a diameter of 35 cm, when the irradiation is to be performed by a linear accelerator and a cobalt-60 teletherapy unit, respectively. Calculated values of relative doses varied from 93% to 100% in the smaller volume, and from 66% to 100% in the largest one. A difference of 5.0%, approximately, was observed between calculated and experimental data. The size of these volumes permits the irradiation of blood bags in only one bath without compromising the homogeneity of the absorbed dose over the irradiated volume. Thus, these irradiation volumes can be recommend to minimize the irradiation time when a teletherapy unit is used to irradiate blood. (C) 2010 Elsevier Ltd. All rights reserved.
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Background: In severe aplastic anaemia, the treatment of choice for young patients with a human leucocyte antigen-matched sibling is now established as allogeneic bone marrow transplantation (BMT). In older patients and in those without a matched sibling donor, immunosuppressive therapy is the usual first option. 'Alternative' marrow donors are emerging as an option for those without a matched sibling donor. Aims: To review 10 years of local experience in treating severe aplastic anaemia with BMT and immunosuppressive therapy with emphasis on long-term outcomes. Methods: A retrospective analysis was performed of all patients with severe aplastic anaemia presenting to the Royal Brisbane and Royal Children's Hos- pitals between 1989 and 1999. Data were abstracted regarding patient demographics, pretreatment characteristics and outcome measures, including response rates, overall survival and long-term complications. Results: Twenty-seven consecutive patients were identified, 12 treated with immunosuppression alone and 15 with BMT. In these two groups, transfusion independence was attained in 25% and 100%, respectively, with overall survival being 36% and 100%, respectively. Those treated with immunosuppression were significantly older (median 41.5 versus 22 years, P = 0.008). Long-term survivors of either treatment had extremely low morbidity. Three patients carried pregnancies to term post-transplant. Three patients received alternative donor BMT with correspondingly excellent survival. Conclusions: Patients treated with allogeneic BMT for severe aplastic anaemia enjoyed extremely good long-term survival and minimal morbidity. Patients treated with immunosuppressive therapy had a poorer outcome reflecting their older age and different usage of therapies over the past decade. Optimal treatment strategies for severe aplastic anaemia remain to be determined.
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Mast cells are mobile granule-containing secretory cells that are distributed preferentially about the microvascular endothelium in oral mucosa and dental pulp. The enzyme profile of mast cells in oral tissues resembles that of skin, with most mast cells expressing the serine proteases tryptase and chymase. Mast cells in oral tissues contain the pro-inflammatory cytokine tumour necrosis factor-alpha in their granules, and release of this promotes leukocyte infiltration during evolving inflammation in several conditions, including lichen planus, gingivitis, pulpitis, and periapical inflammation, through induction of endothelial-leukocyte adhesion molecules. Mast cell synthesis and release of other mediators exerts potent immunoregulatory effects on other cell types, while several T-lymphocyte-derived cytokines influence mast cell migration and mediator release. Mast cell proteases may contribute to alterations in basement membranes in inflammation in the oral cavity, such as the disruptions that allow cytotoxic lymphocytes to enter the epithelium in oral lichen planus. A close relationship exists among mast cells, neural elements, and laminin, and this explains the preferential distribution of mast cells in tissues. Mast cells are responsive to neuropeptides and, through their interaction with neural elements, form a neural immune network with Langerhans cells in mucosal tissues. This facilitates mast cell degranulation in response to a range of immunological and non-immunological stimuli. Because mast cells play a pivotal role in inflammation, therapies that target mast cell functions could have value in the treatment of chronic inflammatory disorders in the oral cavity.
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OBJECTIVE: To assess longitudinally the antiviral immune response of T cells from patients with multiple sclerosis (MS) treated with fingolimod (FTY) vs other disease-modifying treatments (DMTs). METHODS: We assessed cellular immune responses specific to influenza virus (FLU), JC virus (JCV), and varicella-zoster virus (VZV) using quantification of interferon-γ secretion by enzyme-linked immunospot in patients with MS on FTY (n = 31), including 2 with herpes zoster (HZ), natalizumab (n = 11), and other DMTs (n = 11). We used viral lysates for FLU and VZV and a pool of peptides for FLU, JCV (VP-1), and VZV (IE63). RESULTS: Besides an expected drop of T cells, we found that, proportionally to the number of CD3(+) T cells, only FTY-treated patients with MS exhibited an increased VZV/IE63-specific T cell response peaking 6 months into treatment, a response that returned to baseline after 12 and 24 months. Two FTY-treated patients developed an HZ 6 months into treatment, coinciding with an absent VZV/IE63-specific T cell response. However, cellular immune responses specific to VZV lysate, JCV, and FLU (lysate and pool of peptide epitopes) were similar between all 3 categories (FTY, natalizumab, and other DMTs) of study patients. CONCLUSIONS: FTY-treated patients with MS exhibit an increased VZV/IE63-specific cellular immune response after 6 months of treatment. FTY-treated patients who develop an HZ are not able to mount such a response, suggesting that a T cell response directed against this viral protein may be key in preventing the occurrence of HZ.
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Tumor necrosis factor (TNF)/TNF receptor (TNFR) superfamily members play essential roles in the development of the different phases of the immune response. Mouse LIGHT (TNFSF14) is a type II transmembrane protein with a C-terminus extracellular TNF homology domain (THD) that assembles in homotrimers and regulates the course of the immune responses by signaling through 2 receptors, the herpes virus entry mediator (HVEM, TNFSFR14) and the lymphotoxin β receptor (LTβR, TNFSFR3). LIGHT is a membrane-bound protein transiently expressed on activated T cells, natural killer (NK) cells and immature dendritic cells that can be proteolytically cleaved by a metalloprotease and released to the extracellular milieu. The immunotherapeutic potential of LIGHT blockade was evaluated in vivo. Administration of an antagonist of LIGHT interaction with its receptors attenuated the course of graft-versus-host reaction and recapitulated the reduced cytotoxic activity of LIGHT-deficient T cells adoptively transferred into non-irradiated semiallogeneic recipients. The lack of LIGHT expression on donor T cells or blockade of LIGHT interaction with its receptors slowed down the rate of T cell proliferation and decreased the frequency of precursor alloreactive T cells, retarding T cell differentiation toward effector T cells. The blockade of LIGHT/LTβR/HVEM pathway was associated with delayed downregulation of interleukin-7Rα and delayed upregulation of inducible costimulatory molecule expression on donor alloreactive CD8 T cells that are typical features of impaired T cell differentiation. These results expose the relevance of LIGHT/LTβR/HVEM interaction for the potential therapeutic control of the allogeneic immune responses mediated by alloreactive CD8 T cells that can contribute to prolong allograft survival.
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Pós-graduação em Cirurgia Veterinária - FCAV
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Purpose: To report the clinical outcome of the treatment of dry eyes using 0.03% tacrolimus eye drops (olive oil + tacrolimus 0.03%) (Ophthalmos, Sao Paulo, Brazil). Methods: Sixteen eyes of 8 patients with Sjogren syndrome dry eyes (age, 51.13 +/- 9.45 years) were enrolled in this study (prospective noncontrolled interventional case series). Patients were instructed to use topical 0.03% tacrolimus eye drops twice a day (every 12 hours) in the lower conjunctival sac. Schirmer I test, break-up time, corneal fluorescein, and rose bengal staining score were performed in all patients 1 day before, and 14, 28, and 90 days after treatment with 0.03% tacrolimus eye drops. Results: The average fluorescein staining and rose bengal staining scores improved statistically significantly after 14 days of treatment and improved even more after 28 and 90 days. The average Schirmer I test did not improve statistically significantly after 28 days of treatment, although we did observe a significant improvement after 90 days of treatment with 0.03% tacrolimus eye drops. The average break-up time did not improve statistically after 14 days of treatment, although we observed a significant improvement after 28 and 90 days of treatment with 0.03% tacrolimus eye drops. Conclusions: Topical 0.03% tacrolimus eye drops successfully improved tear stability and ocular surface status in patients with dry eyes.
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AIMS To investigate whether drugs others than mycophenolic acid and ipilimumab might cause graft-versus-host-like apoptotic enteropathy, the clinicopathological findings in four patients were examined who had developed watery diarrhoea and apoptotic enteropathy (three cases from colon and one case from ileal pouch) after intake of antimetabolites (methotrexate and capecitabine) and/or tumour necrosis factor-α inhibitors (etanercept and infliximab). METHODS The clinical charts, endoscopy reports and intestinal biopsies from all endoscopies were reviewed for all patients. Biopsies were evaluated semiquantitatively for apoptosis of basal crypts, dilated damaged crypts, defined as cystically dilated crypts with flattened degenerated epithelium containing apoptotic debris and few neutrophils, and mucosal architecture. Further, the presence of intraepithelial lymphocytes, chronic inflammatory cells in the lamina propria and mucosal ulcerations was recorded and immunohistochemical analysis for human cytomegalovirus and herpes simplex virus was performed. RESULTS Endoscopic examination revealed normal mucosa in two patients, whereas the other two showed focal ulcerations. Histological changes included increased apoptosis of basal crypts, the presence of dilated damaged crypts and architecture distortion. In all cases, a temporal association between drug intake and/or dose increase, and onset of diarrhoea, was observed, and no convincing evidence of other potentially underlying causes of colitis/enteritis was found, including infections. CONCLUSIONS Pathologists should be aware of the expanding spectrum of drugs that can cause apoptotic enteropathy, including antimetabolites and tumour necrosis factor-α inhibitors.
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The intensely studied MHC has become the paradigm for understanding the architectural evolution of vertebrate multigene families. The 4-Mb human MHC (also known as the HLA complex) encodes genes critically involved in the immune response, graft rejection, and disease susceptibility. Here we report the continuous 1,796,938-bp genomic sequence of the HLA class I region, linking genes between MICB and HLA-F. A total of 127 genes or potentially coding sequences were recognized within the analyzed sequence, establishing a high gene density of one per every 14.1 kb. The identification of 758 microsatellite provides tools for high-resolution mapping of HLA class I-associated disease genes. Most importantly, we establish that the repeated duplication and subsequent diversification of a minimal building block, MIC-HCGIX-3.8–1-P5-HCGIV-HLA class I-HCGII, engendered the present-day MHC. That the currently nonessential HLA-F and MICE genes have acted as progenitors to today’s immune-competent HLA-ABC and MICA/B genes provides experimental evidence for evolution by “birth and death,” which has general relevance to our understanding of the evolutionary forces driving vertebrate multigene families.