15 resultados para IgA anti-tissue transglutaminase antibody

em Deakin Research Online - Australia


Relevância:

100.00% 100.00%

Publicador:

Resumo:

A role for α4 and β7 integrins in mediating leucocyte entry into the central nervous system in the multiple sclerosis (MS)-like disease experimental autoimmune encephalomyelitis (EAE) has been demonstrated. However, the individual contributions of their respective ligands mucosal addressin cell adhesion molecule-1 (MAdCAM-1), vascular cell adhesion molecule-1 (VCAM-1) and E-cadherin expressed on the blood-brain barrier has not been determined. In the present paper, it is shown that an antibody directed against MAdCAM-1, the preferential ligand for α4β7, effectively prevented the development of a progressive, non-remitting, form of EAE, actively induced by injection of myelin oligodendrocyte glycoprotein peptide (MOG(35-55)) autoantigen. Combinational treatment with both anti-MAdCAM-1, VCAM-1, and intercellular adhesion molecule-1 (ICAM-1) (ligand for integrin lymphocyte function-associated antigen (LFA)-1) mAbs led to more rapid remission than that obtained with anti-MAdCAM-1 antibody alone. However, neither MAdCAM-1 monotherapy, nor combinational antibody blockade was preventative when administered late in the course of disease progression. In conclusion, MAdCAM-1 plays a major contributory role in the progression of chronic EAE and is a potential therapeutic target for the treatment of MS. Critically, antivascular addressin therapy must be given eaA role for alpha4 and beta7 integrins in mediating leucocyte entry into the central nervous system in the multiple sclerosis (MS)-like disease experimental autoimmune encephalomyelitis (EAE) has been demonstrated. However, the individual contributions of their respective ligands mucosal addressin cell adhesion molecule-1 (MAdCAM-1), vascular cell adhesion molecule-1 (VCAM-1) and E-cadherin expressed on the blood-brain barrier has not been determined. In the present paper, it is shown that an antibody directed against MAdCAM-1, the preferential ligand for alpha4beta7, effectively prevented the development of a progressive, non-remitting, form of EAE, actively induced by injection of myelin oligodendrocyte glycoprotein peptide (MOG(35-55)) autoantigen. Combinational treatment with both anti-MAdCAM-1, VCAM-1, and intercellular adhesion molecule-1 (ICAM-1) (ligand for integrin lymphocyte function-associated antigen (LFA)-1) mAbs led to more rapid remission than that obtained with anti-MAdCAM-1 antibody alone. However, neither MAdCAM-1 monotherapy, nor combinational antibody blockade was preventative when administered late in the course of disease progression. In conclusion, MAdCAM-1 plays a major contributory role in the progression of chronic EAE and is a potential therapeutic target for the treatment of MS. Critically, antivascular addressin therapy must be given early in the course of disease prior to the establishment of irreversible damage if it is to be effective, as a single treatment modality.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Liver metastasis is the major obstacle for prolonging the survival of colon cancer patients. Low-molecular-weight heparin (LMWH), a common drug for venous thromboembolism, has displayed beneficial effects in improving the survival of cancer patients, though the mechanism remains unclear. This study aimed to investigate the effects of LMWH on hepatic metastasis of colon cancer and its underlying molecular mechanism by targeting the interaction of the chemokine receptor CXCR4 and its ligand CXCL12 (formerly known as stromal cell-derived factor 1α, SDF-1α), as the CXCR4-CXCL12 axis has been shown to regulate the interaction of cancer cells and stroma. Experimental results revealed that LMWH (Enoxaparin, 3500-5500 Da) inhibited the CXCL12-stimulated proliferation, adhesion and colony formation of human colon cancer HCT-116 cells that highly expressed CXCR4. Interestingly, LMWH or an anti-CXCR4 blocking antibody diminished the migrating and invading abilities of HCT116 cells stimulated by the recombinant CXCL12 protein or liver homogenates which contained endogenous CXCL12 protein. Although LMWH did not significantly inhibit the growth of subcutaneous colon tumors, it significantly suppressed the formation of hepatic metastasis established by intrasplenic injection of colon cancer cells in nude Balb/c mice and also downregulated the expression of CXCL12 in hepatic sinusoidal endothelial cells. The results suggest that LMWH inhibits the formation of hepatic metastasis of colon cancer by disrupting the interaction of CXCR4 and CXCL12, supporting that perioperative administration of LMWH may help to prevent the seeding and subsequent growth of hepatic metastases of colon cancer cells.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Matrine, one of the main components extracted from a traditional Chinese herb, Sophora flavescens Ait, has displayed anti-cancer activity in several types of cancer cells. This study aims to evaluate the therapeutic benefits of matrine on primary and metastatic breast cancer. Matrine inhibited the viability of and induced apoptosis in human MCF-7 and mouse 4T1 breast cancer cells in a dose-dependent manner in vitro as shown by MTT assay, flow cytometry and laser scanning confocal microscopy. Administration of matrine inhibited the growth of primary tumors and their metastases to lungs and livers, in a dose-dependent manner, in a highly metastatic model of 4T1 breast cancer established in syngeneic Balb/c mice. Tumors from matrine-treated mice had a smaller proliferation index, shown by immunostaining with an anti-Ki-67 antibody, a greater apoptosis index, shown by TUNEL-staining, and a less microvessel density, shown by immunostaining with an anti-CD31 A antibody, compared to the controls. Western blot analysis of tumoral homogenates indicated that matrine therapy reduced the ratio of Bcl-2/Bax, downregulated the expressions of VEGF and VEGFR-2, and increased the activation of caspase-3 and caspase-9. This study suggests matrine may be a potent agent, from a natural resource, for treating metastatic breast cancer because of its anti-apoptotic, anti-proliferative and anti-angiogenic activities.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Epithelial cell adhesion molecule (EpCAM) is overexpressed in most solid cancers and is an ideal antigen for clinical applications in cancer diagnosis, prognosis, imaging, and therapy. Currently, most of the EpCAM-based diagnostic, prognostic, and therapeutic strategies rely on the anti-EpCAM antibody. However, the use of EpCAM antibody is restricted due to its large size and instability. In this study, we have successfully identified DNA aptamers that selectively bind human recombinant EpCAM protein. The aptamers can specifically recognize a number of live human cancer cells derived from breast, colorectal, and gastric cancers that express EpCAM but not bind to EpCAM-negative cells. Among the aptamer sequences identified, a hairpin-structured sequence SYL3 was optimized in length, resulting in aptamer sequence SYL3C. The Kd values of the SYL3C aptamer against breast cancer cell line MDA-MB-231 and gastric cancer cell line Kato III were found to be 38±9 and 67±8 nM, respectively, which are better than that of the full-length SYL3 aptamer. Flow cytometry analysis results indicated that the SYL3C aptamer was able to recognize target cancer cells from mixed cells in cell media. When used to capture cancer cells, up to 63% cancer cell capture efficiency was achieved with about 80% purity. With the advantages of small size, easy synthesis, good stability, high binding affinity, and selectivity, the DNA aptamers reported here against cancer biomarker EpCAM will facilitate the development of novel targeted cancer therapy, cancer cell imaging, and circulating tumor cell detection.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

With the successful clinical trials, multifunctional glycoprotein bovine lactoferrin is gaining attention as a safe nutraceutical and biologic drug targeting cancer, chronic-inflammatory, viral and microbial diseases. Interestingly, recent findings that human lactoferrin oligomerizes under simulated physiological conditions signify the possible role of oligomerization in the multifunctional activities of lactoferrin molecule during infections and in disease targeting signaling pathways. Here we report the purification and physicochemical characterization of high molecular weight biomacromolecular complex containing bovine lactoferrin (≥250 kDa), from bovine colostrum, a naturally enriched source of lactoferrin. It showed structural similarities to native monomeric iron free (Apo) lactoferrin (∼78-80 kDa), retained anti-bovine lactoferrin antibody specific binding and displayed potential receptor binding properties when tested for cellular internalization. It further displayed higher thermal stability and better resistance to gut enzyme digestion than native bLf monomer. High molecular weight bovine lactoferrin was functionally bioactive and inhibited significantly the cell proliferation (p<0.01) of human breast and colon carcinoma derived cells. It induced significantly higher cancer cell death (apoptosis) and cytotoxicity in a dose-dependent manner in cancer cells than the normal intestinal cells. Upon cellular internalization, it led to the up-regulation of caspase-3 expression and degradation of actin. In order to identify the cutting edge future potential of this bio-macromolecule in medicine over the monomer, its in-depth structural and functional properties need to be investigated further.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

The chronic systemic administration of d-Galactose in C57BL/6J mice showed a relatively high oxidative stress, amyloid-β expression and neuronal cell death. Enhanced expression of pyknotic nuclei, caspase-3 and reduced expression of neuronal integrity markers further confirmed the aforesaid insults. However, concomitant treatment with the recombinant protein (SurR9-C84A) and the anti-transferrin receptor antibody conjugated SurR9-C84A (SurR9+TFN) nanocarriers showed a significant improvement in the disease status and neuronal health. The beauty of this study is that the biodegradable Food and Drug Administration (FDA) approved poly(lactic-co-glycolic acid) (PLGA) nanocarriers enhanced the biological half-life and the efficacy of the treatments. The nanocarriers were effective in lowering the amyloid-β expression, enhancing the neuronal integrity markers and maintaining the basal levels of endogenous survivin that is essential for evading the caspase activation and apoptosis. The current study herein reports for the first time that the brain targeted SurR9-C84A nanocarriers alleviated the d-Galactose induced neuronal insults and has potential for future brain targeted nanomedicine application.

Relevância:

50.00% 50.00%

Publicador:

Resumo:

Induction of mucosal immunity, particularly to subunit vaccines, has been problematic. The primary hurdle to successful mucosal vaccination is the effective delivery of vaccine antigen to the mucosal associated lymphoid tissue. Physical and chemical barriers restrict antigen access and, moreover, immune responses induced in the mucosa can be biased towards tolerance or non-reactivity. We proposed that these difficulties could be circumvented by targeting antigen to the gastrointestinal associated lymphoid tissue via systemic (parenteral) rather than alimentary routes, using antibodies specific for the mucosal addressin cellular adhesion molecule-1 (MAdCAM). After intravenous or intramuscular injection of such rat antibodies in mice, we found a greatly enhanced (up to 3 logs) anti-rat antibody response. MAdCAM targeting induces a rapid IgA antibody response in the gut and vastly improves the systemic antibody response. Targeting also enhanced T cell proliferation and cytokine responses. Parenteral targeting of mucosal addressins may represent a generic technique for bypassing mucosal barriers and eliminating the need for adjuvants in the induction of proximal and systemic immunity.

Relevância:

50.00% 50.00%

Publicador:

Resumo:

Despite decades of work, an effective HIV vaccine remains elusive. In an effort to elicit protective immunity, investigators have sought to define vaccines able to elicit durable HIV-specific B-cell and T-cell activities. Additionally, vaccines are sought which can induce antibodies of a variety of isotypes, as each isotype possesses unique attributes in terms of opsonization, Fc receptor binding capacity, complement fixation and location. One prominent new vaccine strategy, applied to numerous distinct antigenic systems is the prime boost-regimen, with DNA, vaccinia virus (VV), and/or purified recombinant protein. To examine the durability, location and isotype distribution of responses induced by prime-boost regimens, we tested successive immunizations with DNA, VV and protein (D-V-P), comparing three forms of protein inoculations: (i) purified protein administered intramuscularly with complete Freunds adjuvant, (ii) purified protein administered intranasally, and (iii) purified protein conjugated to oxidized mannan, administered intranasally. We found that all three protocols elicited serum antibodies of multiple isotypes, with serum IgA being most prominent among mice immunized with mannan-conjugated protein. All D-V-P protocols, regardless of protein form or route, also elicited antibody responses at mucosal surfaces. In bronchoalveolar lavage, a tendency toward IgA production was again most prominent in mice boosted with the protein–mannan conjugate. Both B-cell and T-cell responses were sustained for more than 1 year post-immunization following each form of vaccination. Contemporaneous with long-lasting serum and mucosal antibodies were antibody forming cells in the bone marrow of primed animals. Results highlight the D-V-P vaccination strategy as a promising approach for attaining durable, multi-isotype B-cell and T-cell activities toward HIV.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

Plant natriuretic peptide immuno-analogues (irPNP) have previously been shown to affect a number of biological processes including stomatal guard cell movements, ion fluxes and osmoticum-dependent water transport. Tissue printing and immunofluorescent labelling techniques have been used here to study the tissue and cellular localization of irPNP in ivy (Hedera helix L.) and potato (Solanum tuberosum L.). Polyclonal antibodies active against human atrial natriuretic peptide (anti-hANP) and antibodies against irPNP from potato (anti-StPNP) were used for immunolabelling. Tissue prints revealed that immunoreactants are concentrated in vascular tissues of leaves, petioles and stems. Phloem-associated cells, xylem cells and parenchymatic xylem cells showed the strongest immunoreaction. Immunofluorescent microscopy with fluorescein isothiocyanate (FITC)-conjugated goat anti-rabbit IgG supported this finding and, furthermore, revealed strong labelling to stomatal guard cells and the adjacent apoplastic space as well. Biologically active immunoreactants were also detected in xylem exudates of a soft South African perennial forest sage (Plectranthus ciliatus E. Mey ex Benth.) thus strengthening the evidence for a systemic role of the protein. In summary, in situ cellular localization is consistent with physiological responses elicited by irPNPs reported previously and is indicative of a systemic role in plant homeostasis.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

Mannan, oxidatively coupled to recombinant protein antigens, has here been tested as a possible adjuvant for the production of antibody on the mucosa. Given intranasally, but not intraperitoneally, mannan markedly enhanced the production of IgA, IgG1 and IgG2a in the serum, and IgA locally in the lung and at remote mucosal sites, including tears, vaginal and salivary secretions. Oxidative coupling was critical to its action, since neither mannan simply mixed with protein nor mannan–protein conjugates which had been reduced by treatment with sodium borohydride, acted as adjuvants. Oxidatively coupled mannan was compared with the widely studied mucosal adjuvant, cholera toxin (CT). The use of oxidised mannan as an adjuvant induced better responses than CT judged by the induction of IgA in serum, vaginal washings and saliva. Thus, oxidised mannan, which is non-toxic and can be administered without injection, is a suitable adjuvant coupled with protective antigens for vaccinating against a number of infections that occur via the mucous membranes.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

Knowledge of estrogen receptor (ER), progesterone receptor (PgR) and human epidermal growth factor receptor-2 (HER2) status is necessary for determining the optimal treatment of breast cancer patients. At the same time, the discordance between marker profiles (ER/PR and HER2) of primary and metastatic breast cancer is well documented. Whether discordant cases are secondary to “clonal selection” in the face of targeted anti-estrogen or anti-HER2 therapy or whether they are a laboratory artifact is still debated; both scenarios are likely. This article outlines current modalities for ER, PR, and HER2 testing in primary breast carcinoma and its metastases and reviews prospective and retrospective studies that have addressed these issues, as well as recent advances in the field.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

Antigen-specific antibody responses against a model antigen (the B subunit of the heat labile toxin of enterotoxigenic Escherichia coli, LTB) were studied in sheep following oral immunisation with plant-made and delivered vaccines. Delivery from a root-based vehicle resulted in antigen-specific immune responses in mucosal secretions of the abomasum and small intestine and mesenteric lymph nodes. Immune responses from the corresponding leaf-based vaccine were more robust and included stimulation of antigen-specific antibodies in mucosal secretions of the abomasum. These findings suggest that oral delivery of a plant bioencapsulated antigen can survive passage through the rumen to elicit mucosal and systemic immune responses in sheep. Moreover, the plant tissue used as the vaccine delivery vehicle affects the magnitude of these responses.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

mRNA for 14-3-3zeta, an abundant signalling protein in human CNS, is reported as decreased or unchanged in cortex from subjects with schizophrenia. Addressing this dichotomy, using Western blot analyses, we measured levels of 14-3-3zeta proteins in cortex and caudate nucleus from subjects with schizophrenia, bipolar disorder, age/sex matched controls and in analogous CNS regions from rats treated with psychotropic drugs. Anti-14-3-3zeta antibody bound to three proteins (molecular weights: 27, 54 and 70 kDa), in all CNS tissue. Levels of all proteins did not vary with diagnoses (27 kDa: F(2,42.0)=0.35, p=0.71; 54 kDa: F(2,42.1)=0.62, p=0.54; 70 kDa: F(2,41.0)=2.43, p=0.10). By contrast, independent of diagnoses, there were significant increases in the levels of the 27 kDa protein (+32%; p<0.001) and 54 kDa protein (51%; p=0.001) in the caudate nucleus from males compared to females. In addition, there was a trend (-25%; p=0.06) to decreased levels of the 70 kDa protein in BA 9 in males compared to females. Treating with haloperidol, olanzapine, lithium or a combination thereof did not alter 14-3-3zeta levels in rat cortex or striatum. Therefore, this study suggests that 14-3-3zeta proteins are not altered in the cortex or caudate nucleus in schizophrenia, bipolar disorder or in analogous regions in psychotropic drug treated rats. By contrast, our study suggests that levels of 14-3-3zeta in some regions of the human CNS may be modulated by some sex-specific mechanism.