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Structural and functional characteristics of hairy cells.

Morphological, cytochemical, immunological and ultrastructural studies were performed on peripheral blood mononuclear cells from a patient with hairy-cell leukemia. Immunofluorescence studies showed a very strong intensity of fluorescence and indicated that hairy cells had monoclonal surface-membrane immunoglobulins (SmIg) actively produced by the cells. An unusual spontaneous SmIg redistribution induced by antibodies was also noted. Immunoultrastructural studies demonstrated that antibody-induced redistribution of SmIg on hairy cells is in form of a singular polar cap and that the cell membrane is rapidly cleaned of the complexes by endocytosis. The behavior of hairy cells regarding several membrane markers, mitogen stimulation and antibody-induced cytotoxicity suggests that hairy projections could represent the expression of a functional stage common to different lymphocyte subpopulations, or alternatively, a marker of a peculiar subset of B lymphocytes.

Antibodies, Neoplasm↗

Immunological studies in myotonic dystrophy.

Abnormalities of cellular and humoral immunity have been recognised in myotonic dystrophy but their significance is uncertain. To throw further light on this, a group of 22 patients with myotonic dystrophy was investigated, looking specifically for evidence of abnormalities of B lymphocyte function and of disturbed immunoregulation. The previously reported reduction in serum IgG levels was confirmed and, in addition, serum IgA levels were significantly reduced. Autoantibodies to muscle and non-muscle antigens were not found and there was no increase in autoimmune disease or malignancy, suggesting that immunoregulatory mechanisms are not disturbed. The proportions of T and B cells were not significantly different in patients and controls. B-lymphocyte capping with FITC- antihuman IgG was quantitatively altered, the percentage of capped cells after incubation being reduced and the time-course of the capping process being apparently prolonged in the myotonic dystrophy subjects. While there are a number of possible explanations for these findings, they may reflect an intrinsic abnormality of the lymphocyte membrane. This could be part of a more generalised membrane defect which has been suggested to underlie the myotonia and certain other manifestations of this multisystemic disorder.

Adolescent↗

Atypical pathogens in community-acquired pneumonia.

The atypical pathogens are an important and significant cause of CAP. The clinical and radiologic manifestations of CAP caused by these pathogens are modulated by the immunologic and physiologic status of the host, and therefore are not pathogen-specific. The range of frequencies found in various studies for the atypical pathogens among the causes of CAP is broad. These frequencies are affected by very important factors that should be recognized. In a significant percentage of patients, an atypical pathogen can be identified together with an additional cause. The significance of multiple causes has not been clarified sufficiently. The principal diagnostic techniques in use today for the causative diagnosis of CAP are serologic tests. Different serologic methods have been used in various studies and diagnostic criteria are not standardized. In the future it is likely that diagnostic testing will be based on the PCR technique on serum samples. The effectiveness and importance of antimicrobial therapy in some patients with atypical pathogen CAP are unclear. The accepted therapy today for atypical pathogen CAP, which is based on erythromycin, will probably be changed in the near future in favor of the new generations of fluoroquinolone or the new macrolide preparations.

Adult↗

Antigenic/allergenic analysis of basidiomycete cap, mycelia, and spore extracts.

Since airborne basidiospores may be important inducers of respiratory allergy, extracts of spores, caps and mycelia from Pleurotus ostreatus were studied by immunologic techniques. Crossed immunoelectrophoresis of the Pleurotus spore extract showed it to be a complex mixture containing at least 27 precipitating antigens. Crossed-line immunoelectrophoresis comparing Pleurotus spore extract with extracts of Pleurotus cap or mycelia demonstrated both common antigens and antigens unique to the spore extract. Inhibition of Pleurotus spore RAST by extracts of Pleurotus spore, cap, and mycelia suggested that these extracts contained common allergenic components. However, wheal and flare skin reactivity of allergic patients to extracts of P. ostreatus or Cantharellus cibarius demonstrated little correlation between reactivity to cap and spores. These results demonstrate that basidiomycete spore extracts are the best diagnostic reagents to use in clinical studies, although cap and mycelia extracts may provide useful material for further allergen analysis.

Allergens↗

[A study of complement fixation test by trinitrophenyl-cap-liposome: application of viral antibody test].

The complement fixation (CF) test is used as one of the diagnostic laboratory procedures for viral infections. The liposome is employed in the immunological method for basic research and we used the trinitrophenyl-cap-liposome (TNP-L) instead of sensitized erythrocyte for CF test. "TNP-L" consists of a plasma membrane of trinitrophenyl bases sensitized with antibody and is dissolved easily by animal complements. Carboxyfluorescein enclosed in liposome is released in fixed quantities according to liposome dissolution. Therefore, as our conclusion, the above CF method has a good agreement to that of sensitized erythrocyte. TNP-L method has advantages to be able to eliminate the individual differences and shorter storage-term of red blood cells and is also satisfactory for utilization with high reproducibility and intra day precision.

Animals↗

Identification of a novel gene, dep, associated with depolymerization of the capsular polymer in Bacillus anthracis.

Bacillus anthracis produces a gamma-linked poly-D-glutamic acid capsule that is essential for virulence. A 6.2 kb fragment of B. anthracis DNA (cap), when present in Escherichia coli, produces a capsular polymer that is immunologically identical to that produced by B. anthracis. By immunodiffusion analysis of E. coli strains carrying varying portions of the cap region, we identified a novel gene (dep) responsible for degradation of the capsular polymer of B. anthracis. The simultaneous presence of the cap region and the dep gene caused production of low-molecular-weight, degraded capsular polymer both in E. coli and in B. anthracis, whereas the cap region alone caused production of a high-molecular-weight capsule. The dep gene mapped immediately downstream of the cap region within a 1.8 kb fragment and was transcribed in the same direction. This fragment was sequenced and a 1401 bp open reading frame (ORF) was found that is predicted to encode a peptide with molecular weight of 51,460. By in vitro transcription-translation analysis, this ORF was shown to be the dep gene product. The deduced amino acid sequence of the dep product has sequence similarity to E. coli and mammalian gamma-glutamyltranspeptidase (GGT). However, the Dep protein did not have GGT activity. The Dep protein appears to be an enzyme that catalyses the hydrolysis of the poly-D-glutamic acid capsule. Although the biological functions of the dep gene are unknown, it is possible that low-molecular-weight, diffusible polyglutamates produced through the action of the dep gene may act to inhibit host defence mechanisms.

Amino Acid Sequence↗

Vital role of the itch-scratch response in development of spontaneous dermatitis in NC/Nga mice.

BACKGROUND: The itch sensation and the resultant response, scratching, are important symptoms of atopic dermatitis (AD) and have a significant impact on the quality of life of affected patients. However, the influence of the itch-scratch response on the pathology of AD has not been precisely elucidated. OBJECTIVES: To investigate the role of scratching behaviour in the development of spontaneous dermatitis using conventionally raised NC/Nga mice (Conv-NC mice), which are known to be an animal model for human AD. METHODS: Capsaicin-sensitive sensory nerves of the mice were ablated by neonatal capsaicin treatment (Cap-NC mice), and the development of spontaneous dermatitis in the Cap-NC mice was compared chronologically with that in Conv-NC mice. RESULTS: Scratching behaviour was almost completely prevented in Cap-NC mice raised for 84 days under conventional conditions, and the development of dermatitis and elevation of the serum IgE level were significantly suppressed. Histological analysis revealed that the numbers of infiltrating eosinophils and mast cells in the lesional skin of Cap-NC mice were lower than those in Conv-NC mice. Immunological studies showed that the capability of spleen T cells to produce both T-helper (Th) 1 (interferon-gamma) and Th2 [interleukin (IL)-5 and IL-13] cytokines was diminished in Cap-NC mice. Furthermore, serum levels of IL-18 were approximately twice higher in Conv-NC mice than in Cap-NC mice. CONCLUSIONS: These observations suggest that scratching behaviour contributes to the development of dermatitis by enhancing various immunological responses in the murine AD model, implying that prevention of the itch sensation and/or itch-associated scratching behaviour is an effective treatment for AD.

Animals↗

Induction of cellular and humoral immunological responsiveness to a soluble cercarial antigen preparation from Schistosoma mansoni.

The development of immunological responsiveness to a soluble cercarial antigenic preparation (CAP) from Schistosoma mansoni was analyzed in inbred CBA/J mice infected with cercariae, one or multiple times, or sensitized using CAP. Repeated exposure to 75 cercariae at three weekly intervals (3X-75) or subcutaneous administration of 20 mug of CAP (CAP/complete Freund adjuvant [CFA]) stimulated the development of specific anti-CAP lymph node cell blastogenesis. The degree of responsiveness was dependent upon the concentration of CAP in the culture system and was optimal in the dose range of 20 to 30 mug of protein of CAP per culture. Animals exposed once to 75 or 225 cercariae or to two sequential weekly infections with 75 cercariae exhibited a minimal response to CAP in comparison to the responsiveness of 3X-75 or CAP/CFA lymph node cells. Assessment of anti-CAP agglutinating antibody by application of a microtiter passive hemagglutination technique revealed that both 3X-75 and CAP/CFA animals possessed low titers of activity. In addition, both 3X-75 and CAP/CFA sera contained reagin-like antibodies to CAP as detected by the heterologous (rat), 72-h latent period, passive cutaneous anaphylaxis technique.

Animals↗

[Catastrophic antiphospholipid syndrome after ovulation induction].

INTRODUCTION: The catastrophic antiphospholipid syndrome (CAPS) is a rare expression of the antiphospholipid syndrome (APLS). The all predicting factors of happening of CAPS are not yet discovered. Some women presenting an APLS with infertility have recourse to ovulation induction (OI). EXEGESIS: After an OI, a woman is admitted for acute renal failure, hypertension, seizures, respiratory failure. History and immunologic tests are in favour of APLS. Renal biopsy highlights a thrombotic microangiopathy. Diagnosis of CAPS is made. Patient improves after respiratory assistance, parenteral treatment for hypertension and anticoagulant therapy. CONCLUSION: IO seems to be on of the factors which leads to CAPS. To avoid such consequences, it's essential to know the history and the immunological status of the patients having recourse to this treatment to take care of these risked pregnancies.

Acute Disease↗

Purification and initial characterization of a protein from skeletal muscle that caps the barbed ends of actin filaments.

We describe herein the purification of a protein from skeletal muscle that binds to ("caps") the morphologically defined barbed end of actin filaments. This actin-capping protein appeared to be a heterodimer with chemically and immunologically distinct subunits of Mr = 36,000 (alpha) and 32,000 (beta), Rs = 37 A, s20,w = 4.0 S, and a calculated native molecular weight of approximately 61,000. The protein was obtained in milligram quantities at greater than 95% purity from acetone powder of chicken skeletal muscle by extraction in 0.6 M KI, precipitation with ammonium sulfate, sequential chromatographic steps on DEAE-cellulose, hydroxylapatite, and Sephacryl S-200, followed by preparative rate zonal sucrose density gradient centrifugation. In immunoblots of myofibrillar proteins, affinity-purified antibodies selectively recognized protein bands of the same molecular weight as the subunits of the capping protein to which they were made, indicating that the isolated capping protein is a native myofibrillar protein, and not a proteolytic digestion product of a larger muscle protein. A specific interaction of the capping protein with the barbed end of actin filaments was indicated by its ability to inhibit actin filament assembly nucleated by spectrin-band 4.1-actin complex in 0.4 mM Mg2+, accelerate actin filament formation and increase the critical concentration of actin in 2-5 mM Mg2+, 75-100 mM KCl, and inhibit the addition of actin monomers to the barbed end of heavy meromyosin-decorated actin filaments as determined by electron microscopy. All of these effects occurred at nanomolar concentrations of capping protein and micromolar concentrations of actin, suggesting a high affinity interaction.

Actins↗

Phase I/II combined chemoimmunotherapy with carcinoembryonic antigen-derived HLA-A2-restricted CAP-1 peptide and irinotecan, 5-fluorouracil, and leucovorin in patients with primary metastatic colorectal cancer.

PURPOSE: We conducted a phase I/II randomized trial to evaluate the clinical and immunologic effect of chemotherapy combined with vaccination in primary metastatic colorectal cancer patients with a carcinoembryonic antigen-derived peptide in the setting of adjuvants granulocyte macrophage colony-stimulating factor, CpG-containing DNA molecules (dSLIM), and dendritic cells. EXPERIMENTAL DESIGN: HLA-A2-positive patients with confirmed newly diagnosed metastatic colorectal cancer and elevated serum carcinoembryonic antigen (CEA) were randomized to receive three cycles of standard chemotherapy (irinotecan/high-dose 5-fluorouracil/leucovorin) and vaccinations with CEA-derived CAP-1 peptide admixed with different adjuvants [CAP-1/granulocyte macrophage colony-stimulating factor/interleukin-2 (IL-2), CAP-1/dSLIM/IL-2, and CAP-1/IL-2]. After completion of chemotherapy, patients received weekly vaccinations until progression of disease. Immune assessment was done at baseline and after three cycles of combined chemoimmunotherapy. HLA-A2 tetramers complexed with the peptides CAP-1, human T-cell lymphotrophic virus type I TAX, cytomegalovirus (CMV) pp65, and EBV BMLF-1 were used for phenotypic immune assessment. IFN-gamma intracellular cytokine assays were done to evaluate CTL reactivity. RESULTS: Seventeen metastatic patients were recruited, of whom 12 completed three cycles. Therapy resulted in five complete response, one partial response, five stable disease, and six progressive disease. Six grade 1 local skin reactions and one mild systemic reaction to vaccination treatment were observed. Overall survival after a median observation time of 29 months was 17 months with a survival rate of 35% (6 of 17) at that time. Eight patients (47%) showed elevation of CAP-1-specific CTLs. Neither of the adjuvants provided superiority in eliciting CAP-1-specific immune responses. During three cycles of chemotherapy, EBV/CMV recall antigen-specific CD8+ cells decreased by an average 14%. CONCLUSIONS: The presented chemoimmunotherapy is a feasible and safe combination therapy with clinical and immunologic efficacy. Despite concurrent chemotherapy, increases in CAP-1-specific T cells were observed in 47% of patients after vaccination.

Adult↗

A monoclonal antibody against 2,2,7-trimethylguanosine that reacts with intact, class U, small nuclear ribonucleoproteins as well as with 7-methylguanosine-capped RNAs.

A hybridoma secreting a monoclonal antibody (H-20) that recognizes the 2,2,7-trimethylguanosine(m3G)-containing cap structure of U snRNAs was derived from a mouse which was immunized with a m3G-containing human serum albumin conjugate. The antibody specifically reacts with intact small nuclear ribonucleoprotein particles, U snRNPs, and allows the snRNPs U1 to U6 to be isolated in one step from nuclear extracts of eucaryotic cells by affinity chromatography on a preparative scale. Antibody-bound snRNPs are desorbed from the affinity column by elution with excess of the cross-reactive nucleoside 7-methylguanosine (m7G), which guarantees maintenance of their native structure. The 20 affinity column also allows the snRNPs U1, U2 and U5 to be separated from U4/U6 RNPs by sequential elution of the particles with m7G under differential salt concentrations. As determined by competitive radioimmunoassay and protein-A--Sepharose immunoprecipitation, mAb H-20 crossreacts with intact m7G cap structures. In particular we could show that non-denatured m7G-capped SP6/beta-globin RNA was precipitated efficiently by the antibody while GpppG-capped or non-capped RNAs did not react. Thus the monoclonal antibody H-20 should have a wide application, not only for studying the molecular biology and immunology of the U snRNPs from diverse organisms, but also for the characterization and isolation of m7G-capped transcripts.

Animals↗

Isolation and characterization of the yeast mRNA capping enzyme beta subunit gene encoding RNA 5'-triphosphatase, which is essential for cell viability.

The yeast Saccharomyces cerevisiae mRNA capping enzyme is composed of two subunits of alpha (52 kDa, mRNA guanylyltransferase) and beta (80 kDa, RNA 5'-triphosphatase). We have isolated the alpha subunit gene (CEG1) by immunological screening. In this report, with the aid of partial amino acid sequences of purified yeast capping enzyme, we isolated the gene, designated CET1, encoding the S. cerevisiae capping enzyme beta subunit. Amino acid sequence analysis revealed that the gene encodes for 549 amino acids with a calculated M(r) of 61,800 which is unexpectedly smaller than the size estimated by SDS-PAGE. Gene disruption experiment showed that CET1 is essential for yeast cell growth. The purified recombinant CET1 gene product, Cet1, exhibited an RNA 5'-triphosphatase activity which specifically removed the gamma-phosphate from the triphosphate-terminated RNA substrate, but not from nucleoside triphosphates, confirming the identity of the gene. Interaction between the Cet1 and the Ceg1 was also studied by the West-Western procedure using recombinant Ceg1-[32P]GMP as probe.

3-Isopropylmalate Dehydrogenase↗

Antigen-specific electrophoretic cell separation for immunological investigations.

Preincubation of human blood lymphocytes with cell surface antigen specific antibodies under non-capping conditions reduces the electrophoretic mobility of the corresponding lymphocyte subpopulation. Antigen-positive and antigen-negative cells can be separated by free flow electrophoresis with high yield, purity and viability. The use of fluorescence-labelled second antibodies augments the induced decrease in net surface charge density, and allows rapid detection of antigen-positive cells in the fractions of electrophoresis. Carrier-free cell electrophoresis of human peripheral blood lymphocytes after reaction with anti-IgM-antibody or the monoclonal antibodies OKT4 or OKT8, and sandwich staining with tetrarhodamine isothiocyanate-labelled anti-IgG resulted in the large-scale separation of high pure human B and T lymphocyte subpopulations. Their functional integrity was shown in assays of lymphocyte transformation and of antigen-specific induction and regulation of antibody synthesis in vitro. These separate lymphocyte subpopulations are useful tools for immunological investigations. While, for instance, the effects of drugs on human lymphocytes are obscured by coincident changes in cell composition of the peripheral blood tested that do not by themselves reflect whole body immunocompetence, the cell separation and in vitro assays at a defined cell number and cell composition allow the recording of quantitative changes in the function of different cell subpopulations. We studied the influence of the anesthetic thiopental on separated human lymphocyte subsets. In both polyclonal lectin stimulation and in vitro antibody production, thiopental exhibited a noncytotoxic suppression of lymphocyte functions. B-Cells, T-helper and T-suppressor cells were equally affected and showed the same dose response.(ABSTRACT TRUNCATED AT 250 WORDS)

Antibodies, Monoclonal↗

Cooperative modulation by eIF4G of eIF4E-binding to the mRNA 5' cap in yeast involves a site partially shared by p20.

Interaction between the mRNA 5'-cap-binding protein eIF4E and the multiadaptor protein eIF4G has been demonstrated in all eukaryotic translation assemblies examined so far. This study uses immunological, genetic and biochemical methods to map the surface amino acids on eIF4E that contribute to eIF4G binding. Cap-analogue chromatography and surface plasmon resonance (SPR) analyses demonstrate that one class of mutations in these surface regions disrupts eIF4E-eIF4G association, and thereby polysome formation and growth. The residues at these positions in wild-type eIF4E mediate positive cooperativity between the binding of eIF4G to eIF4E and the latter's cap-affinity. Moreover, two of the mutations confer temperature sensitivity in eIF4G binding to eIF4E which correlates with the formation of large numbers of inactive ribosome 80S couples in vivo and the loss of cellular protein synthesis activity. The yeast 4E-binding protein p20 is estimated by SPR to have a ten times lower binding affinity than eIF4G for eIF4E. Investigation of a second class of eIF4E mutations reveals that p20 shares only part of eIF4G's binding site on the cap-binding protein. The results presented provide a basis for understanding how cycling of eIF4E and eIF4G occurs in yeast translation and explains how p20 can act as a fine, but not as a coarse, regulator of protein synthesis.

Amino Acid Sequence↗

[Multitest Fx5 in food allergy].

A comparative study was made of three in vivo and in vitro diagnostic methods for food allergy: Fx5 multitest (Pharmacia); Measurement of specific IgE CAP (Pharmacia); Skin tests (Prick Tests). 20 patients, from 3 to 71 years (mean 24.4 years), were selected by clinical suggestion (asthma, rhinitis, atopic dermatitis, urticaria and/or Quincke's oedema). The Fx5 test used six food allergens: wheat, egg, cow's milk, soya, peanut and fish. The Cap Rast for each substance was evaluated, as was Fx5, by a radio-immunological method. The Prick Tests made with the six allergens used were considered to be positive when the diameter of the weal was greater than that produced by a reference test with histamine. The results were considered as a comparison between Fx5 and Cap Rast to each of the foods, between Fx5 and prick Test with five foods and finally between CAP RAST and Prick Test. Correlation Fx5--Cap rast was better and more useful in the diagnosis of food allergy than skin tests.

Adolescent↗

Biochemical and immunological analysis of rapidly purified 10-nm filaments from baby hamster kidney (BHK-21) cells.

Juxtanuclear birefringent caps (FC) containing 10-nm filaments form during the early stages of baby hamster kidney (BHK-21) cell spreading. FC are isolated from spreading cells after replating by treatment with 0.6 M KCl, 1% Triton X-100 (Rohm & Haas Co., Philadelphia, Pa.) and DNase I in phosphate-buffered saline. Purified FC are birefringent and retain the pattern of distribution of 10-nm filaments that is seen in situ. Up to 90% of the FC protein is resolved as two polypeptides of approximately 54,000 and 55,000 molecular weight on sodium dodecyl sulfate (SDS) polyacrylamide gels. The protein is immunologically and biochemically distinct from tubulin as determined by indirect immunofluorescence, double immunodiffusion, one-dimensional peptide mapping by limited proteolysis in SDS gels, and amino acid analysis. The BHK-21 FC amino acid composition, however, is very similar to that obtained for 10-nm filament protein derived from other sources including brain and smooth muscle. Partial disassembly of 10-nm filaments has been achieved by treatment of FC with 6 mM sodium-potassium phosphate buffer, pH 7.4. The solubilized components assemble into distinct 10-nm filaments upon the addition of 0.171 M sodium chloride.

Amino Acids↗

Detection of an allergen in dog dander that cross-reacts with the major cat allergen, Fel d 1.

BACKGROUND: A considerable proportion of animal-allergic patients are sensitized to both cat and dog allergens but knowledge about cross-reactive allergens in cat and dog dander is limited. OBJECTIVE: To investigate whether dog dander contains an allergen that cross-reacts with the major cat allergen, Fel d 1. METHODS: Recombinant Fel d 1 with the same immunological properties as natural Fel d 1 was used for quantitative (CAP) IgE competition experiments performed with sera obtained from cat-allergic patients (n=36). A Fel d 1 cross-reactive dog allergen was characterized by one- and two-dimensional immunoblotting using rFel d 1 for IgE inhibition experiments and with monospecific, polyclonal rabbit anti-recombinant Fel d 1 antibodies. RESULTS: In 25% of Fel d 1-reactive cat-allergic patients, more than 50% inhibition of IgE reactivity to dog allergens was achieved with recombinant Fel d 1. An Fel d 1 cross-reactive 20 kDa allergen with a pI of approximately 3.4 was detected in dander extracts of several different dog breeds. CONCLUSION: This is the first report demonstrating the presence of an Fel d 1-like allergen in dog dander extracts, which may be responsible for double positivity to cat and dog in serology. However, the clinical relevance of this cross-sensitization needs to be confirmed. These results are important for the diagnostic and therapeutic use of dog dander allergen extracts.

Adult↗