Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Immunologic Capping”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 865 records · Page 48Linked to original sources
PubMed2001

[In vitro assessment of combining osteogenic cells with macroporous calcium-phosphate ceramics].

PURPOSE OF THE STUDY: Bone grafts or bone substitutes are required to fill bone defects resulting from trauma or surgical resection of tumors. Calcium-phosphate ceramics are synthetic bone substitutes which promote new bone formation by osteoconduction. These ceramics possess osteoconductive properties but have no intrinsic osteoinductive capacity. They are unable to induce new bone formation in extraossesous sites. One solution to develop bone substitutes with osteogenic properties would be to associate biomaterials with osteoprogenitors. MATERIALS AND METHODS: We studied the in vitro osteogenic potential of human bone-marrow cells cultured on macroporous calcium phosphate (CaP) ceramic, examining stromal cell proliferation and differentiation. Osteogenic differentiation was evaluated in terms of alkaline phosphatase activity and immunological characterization of the extracellular fibrillar matrix formed by these cells. The specimens were examined by scanning and transmission electron microscopy. RESULTS: Human bone-marrow cells proliferated on CaP ceramic. The proliferating bone-marrow cells expressed an osteoblastic phenotype as shown by alkaline phosphatase activity and synthesis in ceramic pores of an extracellular matrix composed of fibronectin, osteocalcin and collagen I. In addition, numerous microcrystals of apatite precipitated on the fibrillar matrix, producing a mineralized fibrillar network within the ceramic. CONCLUSION: This study demonstrates that human bone-marrow cells cultured on macroporous CaP ceramic do not lose their osteoblastic phenotype even after 21 days of culture, and that they can induce osteogenesis in a CaP ceramic in vitro. This type of new "hybrid material" appears promising for the future.

Bone Marrow Cells↗
PubMed1993

Immunological studies on the pathogenesis of pterygium.

Immunohistochemical, electron microscopic and routine pathological studies were conducted to observe the changes in T-cell subsets, B-cells, plasma cells, and mast cells, and the distributions of immunoglobulins (IgE, IgG, IgA, IgM) and C3 in patients with pterygium. The results were as follows. Massive amounts of infiltrating lymphocytes, predominantly T-cells (CD3+), were found in the substantia propria of the pterygial specimens. The helper-suppressor ratio had risen from 1:2.7 in the normal conjunctiva to 1:1.5. Positive cytoplasmic immunoglobulin staining indicated a plasmocytic infiltration in the lesions as well. Abnormal distributions of immunoglobulins were found, and deposition of immunoglobulins in a granular pattern around the basement membrane of the epithelial layer was seen. Mast cell reactions were found, and a linear correlation between the numbers of lymphocytes and mast cells was shown. Basement membrane destruction in the cap area of the pterygium was also confirmed. These results indicate that an immunologic mechanism, possibly of Types 1, 3 and 4 hypersensitivity, may contribute to the pathogenesis of pterygium.

Basement Membrane↗
PubMedDate not supplied

[Immunological confirmation of allergy in children with hypoimmunoglobulinemia].

UNLABELLED: The recognition of allergy in children with hypoimmunoglobulinemia is very difficult because they have very low level or even lack of specific IgE antibodies. Our research hypothesis was the possibility of detecting the specific sensitization of lymphocytes T to food allergens in children with hypoimmunoglobulinemia and with clinical symptoms of allergy. MATERIAL: 32 children actually treated in our Immunology Outpatients Department due to immunodeficiency connected with hypoimmunoglobulinemia and with clinical suspicion of allergy. METHODS: IgE concentration in serum and IgE specific antibodies to food and pollens were examined by FEIA CAP-SYSTEM. Lymphocyte specific response to allergens (cow's milk, gluten) was examined by classical blast transformation test. Immunological profile of children was also evaluated. RESULTS: In the group of 32 children we recognised: 20 children with predominantly antibody deficiencies (2 - agammaglobulinemia; 8 - CVID; 5 - selective immunoglobulins deficiency; 5 - hypoimmunoglobulinemia of infants) and 12 children who had combined immunodeficiency with hypoimmunoglobulinemia ( 3 - AT; 8 - Nijmegen S; 1 - Di George). The children had atopic dermatitis and clinical symptoms of allergy in respiratory and digestive tracts. Concentration of IgE in serum of children was very low, even < 2KU/L, Pediatric Phadiatop was negative, f2 and f79 were absent. Using lymphocytes transformation test (culture stimulated with cow's milk and gluten antigens) we detected sensitivity to cow's milk in 24 children and additionally in 4 of them sensitivity to gluten. CONCLUSIONS: 1) Laboratory difficulties in allergy diagnosis in children with hypoimmunoglobulinemia by evaluation of specific IgE concentration in serum may by caused by defect in biosynthesis of mentioned antibodies. 2) In children with hypoimmunoglobulinemia the lymphocyte blastic transformation test with specific allergens in cultures has a diagnostic value indicating lymphocytes specific response to allergens.

Adolescent↗
PubMed1985

Basal lamina at the site of spinal cord injury in normal, immunotolerant and immunosuppressed rats.

The cut ends of a rat spinal cord are capped with basal lamina (BL) within 20 days. This BL may block regenerating axons. BL at the transection site in rats made immunologically unresponsive to central nervous system antigens is not significantly different from that of control rats, but rats treated with cyclophosphamide show a less complete BL cap during the first 25 days. This may account for the increased axonal regeneration found in cyclophosphamide-treated rats.

Animals↗
PubMed1981

Characterization of effector cells responsible for cell-mediated cytotoxicity in patients with carcinoma of the prostate.

In earlier experiments it has been shown that cellular cytotoxicity of patients with prostatic carcinoma (CaP) as measured by cytolysis of EB 33 target cells correlates with the extent of their tumor lesion: a high grade of cytotoxicity was observed only when CaP was confined to gland. In order to define a possible in vivo immunological host-tumor interaction, further characterization of the type of effector cell responsible for in vitro killing has been attempted. Effector cells could be either tumor-specific sensitized T cells, K cells, macrophages or NK cells. Antibody-dependent K-cell activity could most likely be excluded, since autologous and homologous serum did not affect the extent of EB 33 killing when added to the test medium. Further separation of effector cells by nylon wool columns resulted in increased cytolysis of EB 33 target cells. This can be due either to tumor-specific T-cell-mediated mechanisms or to an increased natural killer cell activity, as macrophages and B cells were significantly removed by this measure. Separation of T and NK cells is necessary to ascertain the effector cell responsible for the in vitro killing of tumor cells derived from human CaP.

Adult↗
PubMed1976

Studies on the mechanism of phagocytosis. II. The interaction of macrophages with anti-immunoglobulin IgG-coated bone marrow-derived lymphocytes.

We have examined the effect of the distribution of anti-immunoglobulin IgG molecules on the surface of bone marrow-derived lymphocytes upon the interaction of these cells with macrophages. Lymphocytes which were diffusely coated with antibodies to surface immunoglogulin were ingested by macrophages. Lymphocytes which had the same number of anti-immunoglobulin IgG molecules redistributed to one pole of the surface bound to the macrophages' Fc receptors but were not ingested. These results confirm our previous hypothesis that ingestion of an immunologically coated particle requires the sequential, circumferential binding of specific receptors on the plasma membrane of a phagocytic cell to immunologic ligands distributed over the entire particle surface. Macrophages which had bound capped lymphocytes by the macrophages' Fc receptors removed the immune complex caps from the lymphocyte surface without destroying the lymphocytes. These lymphocytes remained attached to the macrophage surface. The finding that macrophages can phagocytize immune complexes from the surface of a cell without destroying the cell to which these complexes are attached may be important in understanding the effects of antigens and antibodies on cells participating in a humoral immune response, in identifying the mechanisms by which chronic viral infections are established, and in defining the roles of blocking antibodies in tumor immunity.

Animals↗
PubMed2026

Mice humanized by syntenic replacement with full-length NLRP3 disease-associated variants model the clinical cryopyrinopathy continuum.

Next-generation sequencing technologies are increasingly used to diagnose genetic disorders, particularly immunological diseases with broad and overlapping immune dysregulation. Cryopyrin-associated periodic syndromes (CAPS) are caused by gain-of-function mutations in NLRP3 and include 3 autoinflammatory diseases spanning a continuum of severity: familial cold autoinflammatory syndrome (FCAS), Muckle-Wells syndrome (MWS), and neonatal-onset multisystem inflammatory disease (NOMID). Linking NLRP3 variants to protein dysfunction and clinical phenotype remains challenging because of genetic modifiers and environmental factors. We report the generation and phenotyping of 5 mouse lines expressing either the common human NLRP3 allele or 1 of 4 CAPS mutations spanning the disease spectrum from FCAS to NOMID. In these lines, the murine Nlrp3 locus is replaced by syntenic integration of the human NLRP3 locus, yielding 1 line with the common allele and 4 lines each carrying a distinct CAPS mutation. Unlike models in which a human mutation is introduced into the mouse protein, these lines recapitulate the spectrum of disease severity observed in humans. These findings support a model in which evaluation of nonsynonymous mutations in mice is optimized when introduced in the context of the human gene. This suggests that species-specific regulation and/or intramolecular epistasis may impact modeling of disease-associated variants.

Animals↗
PubMed2000

[Multilocular fixed drug reaction simulating intertrigo in a diabetic patient].

HISTORY AND CLINICAL FINDINGS: A 57-year-old man with diabetes and hypertension was treated with amoxycillin, clarithromycin and pantoprazole for a gastric ulcer positive for Helicobacter pylori. On the second treatment day he developed inguinal pruritus with erythema. He presented at out-patient clinic on the 5th day suspected of having Candida intertrigo. He had bright red, relatively well-circumscribed erythema, most marked at the edges, mainly over the inguinal region and the inside of the thigh. There were no other symptoms. INVESTIGATIONS AND DIAGNOSIS: Bacteriological and mycological tests of the affected skin were unremarkable. Immunological tests showed a normal total IgE but were negative in the CAP-FEIA test for penicilloyl G, penicilloyl V, amoxycilloyl and ampicilloyl. An epifocal epicutaneous test with amoxycillin and ampicillin (5% each in vaseline and doritin) gave a +2 positive reaction and confirmed a suspected fixed drug reaction. TREATMENT AND COURSE: After amoxycillin had been discontinued and local class III steroids had been administered (mometasone furoate, Ecural) for one week the cutaneous changes disappeared without complication, except for slight hyperpigmentation. H. pylori eradication was continued without further complications using clarithromycin, metronidazole and pantoprazole. The patient was issued with an "allergic to penicillin" card. CONCLUSION: Intertriginous changes during antibiotic treatment may not be due to Candida intertrigo, which is fairly common, but to a prognostically much more important drug reaction.

Amoxicillin↗
PubMed1985

Abnormal OKT4/OKT8 ratio and deranged capping in ataxia-telangiectasia.

Two sisters with ataxia-telangiectasia (A-T) and their parents were investigated for some parameters related to immunological functions. We found a decrease of total mature T lymphocytes, a decrease of OKT4+ helper-inducer T subset, and normal values of OKT8+ suppressor-cytotoxic T subset; a normal decrease of E rosette formation after incubation in vitro with theophylline, with a lowered E rosette capacity in one patient. The responses to phytohemagglutinin (PHA)and concanavalin A (ConA) were lowered. In addition we observed a reduction of basal capping of B lymphocytes in one patient and in her parents: this phenomenon could be related to cytoskeletal disorders, possibly involved in the pathogenesis of the disease.

Adolescent↗
PubMed1992

mRNA capping enzyme. Isolation and characterization of the gene encoding mRNA guanylytransferase subunit from Saccharomyces cerevisiae.

The highly purified yeast mRNA capping enzyme is composed of two separate chains of 52 (alpha) and 80 kDa (beta), responsible for the activities of mRNA guanylyltransferase and RNA 5'-triphosphatase, respectively (Itoh, N., Yamada, H., Kaziro, Y., and Mizumoto, K. (1987) J. Biol. Chem. 262, 1989-1995). The gene encoding the mRNA guanylyltransferase subunit (alpha subunit), CEG1, has been isolated by immunological screening of a yeast genomic expression library in lambda gt11 with polyclonal antibodies directed against purified yeast capping enzyme. The identity of CEG1 was confirmed by epitope selection and by expressing the gene in Escherichia coli to give a catalytically active mRNA guanylyltransferase. The gene is present in one copy per haploid genome, and encodes a polypeptide of 459 amino acid residues. From its primary structure as well as its mRNA size, it was concluded that the alpha and the beta subunits of yeast mRNA capping enzyme are encoded by two separate genes, not as a fused protein. CEG1 is located on the chromosome VII by a pulse-field gel electrophoresis. Gene disruption experiment indicated that CEG1 is essential for the growth of yeast. We have also found another open reading frame (ORF2) which lies in close proximity to CEG1 in our clones and encodes a 450 amino acid-polypeptide of yet unknown function.

Amino Acid Sequence↗
PubMed1983

Lymphosarcoma cell leukemia and other non-Hodgkin's lymphomas in leukemic phase.

Lymphosarcoma cell leukemia has been used to refer to three related clinical syndromes. As originally described, it refers to the invasion of peripheral blood by poorly-differentiated lymphocytic lymphoma. Blood involvement occurs in 10 to 70 percent of patients with poorly-differentiated lymphocytic lymphoma, depending on the methods and criteria used to define leukemic phase, but it may have little impact on the clinical course of such patients. Second, lymphosarcoma cell leukemia can describe a variant of chronic lymphocytic leukemia, presenting clinically without lymphoma. Although not all hematologists recognize this as a distinct entity, others believe that such patients have a poorer prognosis than those with typical chronic lymphocytic leukemia. In the absence of a lymph node biopsy diagnostic of poorly-differentiated lymphocytic lymphoma, the diagnosis of lymphosarcoma cell leukemia should be reserved for cases demonstrating immunologic features of poorly-differentiated lymphocytic lymphoma, namely bright surface immunoglobulin immunofluorescence, normal capping, and low mouse red cell rosette formation. Finally, lymphosarcoma cell leukemia has been used to describe the invasion of blood by other types of lymphoma, including large cell, lymphoblastic, and Burkitt's lymphoma, although these are better designated as the particular lymphoma in leukemic phase. When abnormal cells appear in the blood samples of patients with lymphoma, acute myelogenous leukemia must also always be considered, particularly in patients who have received substantial prior chemotherapy or irradiation.

Diagnosis, Differential↗
PubMed2005

Silencing OCILRP2 leads to intrinsic defects in T cells in response to antigenic stimulation.

We have previously demonstrated that OCILRP2 interaction with its ligand NKRP1f provides a co-stimulatory signal for optimal T cell proliferation and IL-2 production. Here, using RNA interference technology, we will demonstrate that silencing OCILRP2 in vivo leads to intrinsic impairment in T cell response to CD3- and CD28-cross-linking as well as antigenic stimulation. OCILRP2-silenced T cells have reduced cell proliferation and IL-2 production, which can be bypassed by PMA and ionomycin treatment. OCILRP2-silenced T cells also failed to undergo TCR capping and had impaired cytoskeleton reorganization. Moreover, in OCILRP2-silenced T cells, tyrosine phosphorylation of Lck was diminished, while tyrosine phosphorylation of linkers for activation of T cells was unchanged. Interestingly, NF-kappaB activation was also impaired as the result of OCILRP2 silencing. Together, our data strongly support a novel role for OCILRP2 C-type lectin in TCR-mediated signal transduction. The observation that OCILRP2 is involved in TCR capping and cytoskeletal organization suggests that OCILRP2-NKRP1f may facilitate lipid rafts and immunological synapse formation during T cell interaction with antigen presenting cells.

Animals↗
PubMed1982

Ribosome structure. Localization of 7-methylguanosine in the small subunits of Escherichia coli and chloroplast ribosomes by immunoelectron microscopy.

The minor nucleoside 7-methylguanosine occurs in Escherichia coli 16 S ribosomal RNA at a single site. High pressure liquid chromatographic analysis shows that a single residue of 7-methylguanosine is also present in chloroplast 16 S ribosomal RNA, presumably at an analogous position in the sequence. Antibodies to 7-methylguanosine were induced in rabbits and shown to be highly specific for the intact methylated base. These antibodies were reacted with 30 S ribosomal subunits from E. coli and from the chloroplasts of Alaskan peas. These two types of ribosome have been shown to be topographically similar (Trempe, M. R., and Glitz, D. G. (1981) J. Biol. Chem. 256, 11873-11879). Electron microscopy of the subunit-antibody complexes showed similar subunit-IgG monomers and antibody-linked subunit dimers. In greater than 95% of the complexes observed for each type of ribosome, antibody contact was consistent with a single binding site, which places 7-methylguanosine near the junction of the upper one-third and lower two-thirds of the subunit and maximally distant from the platform. The analogous localization in both E. coli and chloroplast 30 S ribosomal subunits lends support to their proposed common evolutionary origin.

Antigen-Antibody Complex↗
PubMed1983

An alternative procedure for the preparation of immunogenic liposomal model membranes.

This investigation describes a new procedure for the preparation of immunogenic liposomes which circumvents the need to synthesize the N-(hapten)-substituted derivatives of phosphatidylethanolamine that were previously employed for this purpose. The method is based on the generation of liposomes containing the N-hydroxysuccinimide (NHS) esters of either palmitic acid, cholesteryl-hemisuccinate, or N-succinyl-phosphatidylethanolamine. Reaction of these preformed liposomes with a hapten that possesses a substitutable amino group (e.g., DNP-lysine) results in covalent attachment of the hapten to the lipid bilayers. As a consequence of this binding, the liposomes can elicit formation of hapten-specific plaque-forming cells in mice. The reliability of this procedure is indicated by the fact that these liposomes share the essential immunological properties of liposomes sensitized by incorporation of N-substituted phosphatidylethanolamine derivatives (e.g., DNP-Cap-PE). Thus, the magnitude of the response was found to be dependent on: (a) the presence of lipid A in the liposomes; (b) the phospholipid composition of the liposomes; (c) the distance separating the DNP determinant from the liposomal surface. Additional applications of liposomes, which contain the NHS esters, are indicated.

Animals↗
PubMed2006

Protein glycosylation in Parelaphostrongylus tenuis--first description of the Galalpha1-3Gal sequence in a nematode.

The white-tailed deer is the definitive host of the parasitic nematode Parelaphostrongylus tenuis. This parasite also infects a wide variety of domesticated livestock, causing a debilitating neurologic disease. Glycoconjugates are becoming increasingly implicated in nematode strategies to maintain persistent infections in immunologically competent hosts. In this study, we have carried out detailed mass spectrometric analysis together with classical biochemical techniques, including western blotting and immunohistochemical staining with anticarbohydrate monoclonal antibodies and have shown that P. tenuis contains complex-type N-glycans with the antennae capped with Galalpha1-3Galbeta1-4GlcNAc sequence. By mimicking a vertebrate glycan, Galalpha1-3Gal may aid the parasite in evading immunological detection by the host. This is the first report of the Galalpha1-3Gal sequence in a nematode.

Animals↗
PubMed2005

Evaluation of the automated coagulation analyzer Sysmex CA-7000.

The Sysmex CA-7000 is a fully automated multiparameter hemostasis analyzer equipped with a photo-optical clot detection unit and a cap-piercing system. It is designed to perform coagulation tests as well as chromogenic and immunologic assays. It was evaluated in a coagulation laboratory of a university hospital with respect to its technical characteristics in the determination of routine coagulation (prothrombin time, activated partial thromboplastin time, fibrinogen and single coagulation factors), chromogenic (antithrombin, and anti-FXa activity) and immunologic assays (von Willebrand factor). The intra-assay and inter-assay coefficients of variation (CV) were below 5% for most parameters both in the normal and in the pathological range (exceptions: intra-assay CV=5.2% for the fibrinogen and 5.1% for antithrombin in the low range of concentrations; and inter-assay CV=5.7% and 7.2% for clotting factors V and VII levels in the normal ranges, and in the range from 6.1% to 7.8% for anti-FXa activity). No significant interference could be demonstrated with hemolytic and icteric samples as demonstrated by results similar to those obtained using a mechanical clot detection-based analyzer (STAR). No carryover was detected in alternating measurements of heparinized (1.0 IU/mL unfractionated heparin) and normal plasma samples. The results of the different coagulation, chromogenic and immunologic assays obtained with the CA-7000 analyzer were well correlated with those obtained on the STAR analyzer (r in the range from 0.885 to 0.990). Our results demonstrated that using the CA-7000 analyzer, routine coagulation testing can be performed with satisfactory precision and the same applied to more specialized and specific tests such as single factor activity or antigen concentration.

Blood Coagulation Tests↗
PubMedDate not supplied

Antigen-specific IgG elicited in subjects with prostate cancer treated with flt3 ligand.

Identifying appropriate prostate cancer-associated antigens is critical to the development of immunologic treatments for prostate cancer. Flt3 ligand, a growth and differentiation factor for dendritic cells, has shown modest clinical activity in prostate cancer, presumably by eliciting anti-cancer immune responses. The authors previously reported the results of a clinical trial in which some patients with metastatic prostate cancer treated with flt3 ligand developed autoimmune hypothyroidism with thyroid-specific antibodies. Given these findings, the authors hypothesized that anti-prostate immune responses might also have been elicited in some subjects treated with flt3 ligand. The authors now report the identification of prostate-associated proteins immunologically recognized in 13 prostate cancer patients treated with multiple cycles of flt3 ligand. Using a normal prostate cDNA expression library, and sera from subjects before and after treatment with flt3 ligand, a modified SEREX approach was used to identify six proteins to which IgG immune responses were augmented after flt3 ligand treatment compared with pretreatment. IgG responses to one protein, MAD-CaP-5, were not detectable in any of the subjects' sera before treatment but were elicited after therapy in one subject. The authors suggest that MAD-CaP-5 could be explored as a novel prostate cancer antigen, and that this approach can be used to identify immunologically recognized proteins following any specific intervention.

Antibodies, Neoplasm↗
PubMed2005

The controversy of combination vs monotherapy in the treatment of hospitalized community-acquired pneumonia.

BACKGROUND: The majority of community-acquired pneumonia (CAP) patients (about 80%) will be treated as outpatients, because therapy with a single agent will work. For the remaining 20% of patients requiring hospitalization, there is some growing debate regarding the efficacy of different management approaches. For hospitalized patients, monotherapy with a respiratory fluoroquinolone agent seems to be gaining popularity, but dual therapy combining a beta-lactam and an advanced macrolide still represents a good choice. Indeed, this regimen was recommended for all of the inpatient categories in the latest Infectious Disease Society of America CAP guidelines in 2003. AIM: The purpose of this review was to examine the current clinical evidence to support one option or the other by gathering all of the available published literature. We will review the existing controversies in terms of microbiology, immunology, and clinical outcomes comparing dual therapy (ie, with any combination of beta-lactams, macrolides, or fluoroquinolones) with monotherapy in the treatment of CAP. RESULTS: For the vast majority of patients with CAP (ie, outpatients and inpatients on medical wards), the type of antibiotic regimen prescribed does not have any significant impact. For patients with severe pneumonia, for which there is no accepted definition so far, the controversy remains alive. Mortality from pneumococcal pneumonia has been reduced over the last decades, but despite improved medical care, bacteremic pneumococcal pneumonia is still as lethal as ever, probably because of the aging population, the greater number of immunocompromised patients, and the number of patients with frequent comorbid conditions. Worldwide, the increasing rates of resistance of Streptococcus pneumoniae to antibiotics are also a serious concern, and the clinical implications are not always obvious. Although limited in number, the four studies showing the importance of adding a macrolide to a beta-lactam regimen for the treatment of bacteremic S pneumoniae pneumonia are retrospective and nonblinded, the findings are consistent, and they point to a trend that has to be explored more thoroughly. Studies published in the last few years suggest that combination therapy may be superior for bacteremic S pneumoniae pneumonia. CONCLUSION: In the meantime, for practical purposes, patients hospitalized with a diagnosis of severe CAP may benefit from a dual antibiotic therapy combining a third-generation cephalosporin and a macrolide. For the majority of hospitalized patients with CAP who are not severely ill, fluoroquinolone monotherapy remains an approved, tested, and reliable option. Indeed, the time for more aggressive outpatient fluoroquinolone therapy may reduce the number of patients who are hospitalized with CAP. Independent prospective studies comparing combination therapy with standard monotherapy are urgently required for hospitalized patients with severe CAP.

Anti-Bacterial Agents↗