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Biomedical subjects

G Virella

Publications and source records attributed to G Virella.

At least 163 records · Page 9Linked to original sources
PubMed1978

A practical method for quantitation of antibody responses to tetanus and diphtheria toxoids in normal young children.

Antibodies to diphtheria and tetanus toxoids were assayed in 46 children from 16 to 33 months of age following vaccination. A reversed rocket immunoelectrophoretic technique was used for antibody determination. This method is simple and consistent, and although the limit of detection for antibodies of both types (about 1 U/ml) is above the normal range for primary immune responses, antibody levels in immunized children five weeks after a second injection of vaccine were within measureable range in all but two of the children studied. Levels more than one standard deviation above the mean were found in one child for both antitetanus and anti-diphtheria and in four children for anti-tetanus toxoid antibody only. All four of the high responders to tetanus toxoid were Black, carrying both Black and Caucasian Gm haplotypes. The two apparent nonresponders were Caucasian. All children had normal immunoglobulin levels, except for one with low IgA, who showed normal antibody responses to both toxoids. The results suggest that measurements of precipitating antibodies to diphtheria and tetanus toxoids provide a practical index of humoral immune function in small children.

Antibodies, Viral↗
PubMed1977

The sensitivity to plasmin digestion of human IgG proteins of different heavy chain subclasses.

Normal IgG and purified IgG proteins of all 4 subclasses were digested with plasmin. As expected, IgG3 proteins were highly susceptible to degradation. Usually, activation with streptokinase resulted in faster and more accentuated degradation, but normal IgG was more intensely degraded by nonactivated plasmin. The presence of plasmin activators in IgG preparation might account for this observation.

Enzyme Activation↗
PubMed1977

Urinary lysozyme phenotypes in monocytic leukemia.

A method of two-dimensional electrophoresis has been devised to allow the study of the electrophoretic mobility of urinary lysozyme. Three different phenotypes have been defined in a study of thirteen purified lysozymes obtained from different patients with monocytic leukemia.

Electrophoresis↗
PubMed1977

Immunologic responses to a murine mammary adenocarcinoma. I. Passive transfer of immunity by sera from tumor-bearing mice.

DBA/2 mice bearing a syngeneic mammary adenocarcioma T1699 produced high levels of tumor-specific antibody, detected by indirect immunofluorescence and subsequently identified as the IgG2a subclass. Tumor-bearer sera passively administered to normal recipients protected the animals from subsequent challenge with T1699 tumor cells butnot from challenge with a non-cross-reacting syngeneic tumor, SaD2 fibrosarcoma. Administration of sera prior to tumor challenge was found to be more effective than treatment after the challenge. The protective effect of sera appeared to parallel both antibody titers and appearance of concomitant immunity; however, sera absorbed with T1699 cells, with the indirect fluorescent antibody titers reduced more than 100-fold, conferred an almost identical level of protection. Immune suppression of serum recipients before serum transfer abolished the effect, suggesting that protection depended on a cellular immune response by the host in addition to the possible protective effect(s) of humoral antibody.

Adenocarcinoma↗
PubMed1977

Electrophoresis of lysozyme into Microscoccus-containing agarose gel: quantitative and analytical applications.

Electrophoresis of lysozyme into agarose gel containing Micrococcus lysodeikticus causes lysis of the microorganism, allowing the development of two methods, one for quantitation ("lyso-rocket electrophoresis") and the other for electrophoretic characterization ("crossed lyso-electrophoresis") of lysozyme. The lyso-rocket technique provides an alternative to the method currently used for quantitative assay. By the use of crossed lyso-electrophoresis we have provided evidence, for the first time, of the electrophoretic heterogeneity of urinary lysozyme from patients with monocytic leukemia. We halve also documented the influence of concentration on the electrophoretic mobility of lysozyme.

Body Fluids↗
PubMed1977

Asynchronous development of two monoclonal proteins (IgM lambda and delta 1 chains) in a patient with abdominal lymphoma.

An IgM paraprotein was detected in a patient with abdominal lymphoma. Due to some doubts about the malignant nature of the situation, no cytostatic drugs were administered. When seen two years later the patient had considerably deteriorated in clinical status, with evidence of extra-abdominal involvement. At this time he presented a second paraprotein of low of molecular weight (74,000 to 80,000), consisting of two covalently linked delta1-chain fragments.

Abdominal Neoplasms↗
PubMed1977

Isolation of soluble immune complexes by affinity chromatography using staphylococcal protein A--Sepharose as substrate.

This report describes a technique for the general isolation of immune complexes, based on a combination of gel filtration and affinity chromatography. The first step is the preparation of a globulin-enriched fraction by precipitation with ammonium sulfate at 50% saturation, or of an immune-complex-enriched fraction by precipitation with 5% polyethylene glycol 6000. The enriched fraction is then subfractionated by gel filtration in Ultrogel AcA 34. The immune complexes elute close to the void volume in the macroglobulin peak, separated from monomeric IgG molecules. This peak (sometimes subdivided into two fractions) is then submitted to affinity chromatography on a protein A--Sepharose cooumn. Most immune complexes contain IgG molecules and therefore bind to the column. Almost no protein is bound when normal serum is fractionated according to this method, and no immunoglobulins are detectable in the acid-eluted fraction from the protein A--Sepharose column. In two patients with soluble immune complexes in their sera we eluted immunoglobulin-containing fractions from the column; in one, these fractions had high rheumatoid factor titers; and in the second, with a clinical diagnosis of systemic lupus erythematosus, a similar fraction contained RNA.

Antigen-Antibody Complex↗
PubMed1977

New method for obtaining IgA-specific protease.

A simple method for obtaining an active preparation of IgA-specific protease from a bacterial source is presented. In this method Streptococcus sanguis was inoculated onto the surface of a dialysis membrane on nutrient agar. Following growth, the membrane was removed from the agar surface and washed in a small volume of buffer. A solution with protease activity against IgA1 monoclonal proteins was obtained by clarification of the wash and appeared to be similar to enzyme preparations obtained by other methods.

Antibody Specificity↗
PubMed1977

Antibodies to Candida albicans in IgA-deficient humans.

Titers of serum antibody to Candida albicans were studied in 111 IgA-deficient subjects by the passive hemagglutination method. Circulating antibodies to C. albicans (mean titer, 1:7) were found in only 7.3% of the 111 subjects, as compared with 80% of 137 controls (mean titer, 1:16). However, two IgA-deficient patients with systemic candidiasis were positive for these antibodies (mean titer, 1:64). Indirect immunofluorescence tests indicated that the antibody response in IgA-deficient subjects to superficial or deep-seated infection with C. albicans consists mainly of immunoglobulins of the IgG rather than of the IgM class.

Antibodies, Fungal↗
PubMed1977

Atypical B cell dyscrasia with Bence-Jones proteinuria and intracellular retention of gamma-chains.

A case of atypical B cell dyscrasia is described. The patient presented with a history of weakness, bone pain, and bleeding. A K-type paraprotein was found in serum and urine. The histology of bone marrow was that of a malignant lymphoma, but no enlargement of peripheral lymphoid organs was detectable. Peripheral blood lymphocytes were increased in number and included two populations of immature cells, one lymphoid and the other lymphoplasmocytoid. Immunofluorescent staining showed both populations to contain K and gamma chains in their cytoplasm. The clinicopathological heterogeneity suggests a malignant clone of B cells undergoing incomplete maturation, with arrest at different stages of the cell cycle.

Adult↗
PubMed1977

Multiple myeloma, IgA cryoglobulinemia and serum hyperviscosity in a dog.

Clinical signs of hyperviscosity syndrome in a 6-year-old dog included listlessness, polydipsia, anorexia, vomiting, and recurrent bleeding from the gums. Fundoscopy showed the typical retinal changes associated with this syndrome. A polymeric IgA cryoglobulin characterized in the dog's serum was later isolated and structurally studied. It was found to contain J chain but no secretory component. The heavy and light chains were covalently bound.

Animals↗
PubMed1977

Selective transport of an oligomeric IgA into canine saliva.

Evidence is presented which shows that an oligomeric IgA myeloma protein possessing J-chain but lacking secretory component, is selectively transferred from serum into canine saliva. The data also demonstrate that 125I-label remains with the IgA during the transfer process. These data interpreted in the light of findings in humans support the concept that the oligomeric form of IgA, devoid of secretory component, is required to achieve selective transport.

Animals↗
PubMed1977

Immunocytochemical localization of lysozymes in respiratory and other tissues.

Immunostaining paraffin sections of appropriately fixed tissues with an antiserum to human urinary lysozyme as the primary step in an immunoglobulin-peroxidase bridge method has localized lysozyme in previously recognized sites such as Paneth cells, renal tubules, and lymph node macrophages in several species. In addition, lysozyme was demonstrated in the ciliary layer of the trachea, and type II pneumocytes, as well as cells of presumed mucoid nature in laryngotracheal glands. Large stellate cells in follicle centers in the lymph nodes and spleen and in the medulla of the thymus evidenced strong lysozyme reactivity. Granular pneumocytes disclosed immunoreactivity for lysozyme also at the ultrastructural level. Lysoplate assay demonstrated lysozyme in abundance in both the cellular pellet and acellular supernatant of rat alveolar wash fluid and in rat lung after repeated washing of alveoli. Hamster lung differed from the others in failing to immunostain for lysozyme and affording no evidence for content of lysozyme as determined by lysoplate assay. Sites stained with antiserum to human urinary lysozyme failed to stain with antiserum to egg white lysozyme. However, the pyloric glands, Golgi elements in intestinal epithelium, the surface of the colon, and the proximal straight renal tubule of the mouse stained exclusively with the antiserum to hen egg white lysozyme. Many sites staining with antiserum to urinary lysozyme in respiratory, renal, and lymphoid tissue lacked reactivity in control sections exposed to this antiserum after it was absorbed with purified urinary lysozyme. However, mucous acini in submandibular glands, although failing to stain with other control procedures, retained towared the absorbed antiserum, possibly through reacting with an antibody other than that for human urinary lysozyme. A number of cell types containing proteinaceous cytoplasmic granules stained in control sections exposed to normal serum in place of antilysozyme serum in the immunoglobulin-peroxidase bridge procedure and, thus, possessed selective, but nonimmunospecific affinity for immunoglobulin. Cell types that stained with antiserum to hen egg white lysozyme lost affinity for the antiserum after its absorption with egg white lysozyme but retained the affinity after absorption with urinary lysozyme.

Animals↗
PubMed1977

Immunochemical determination of human lysozyme by laser nephelometry.

The methods currently available for quantitative determination of lysozyme are based on the capacity of the enzyme to lyse Micrococcus lysodeikticus. Previous attempts to develop immunochemical assays have been reported, but the sensitivity was inferior to that of the most widely used lysoplate method. We describe the development of a sensitive immunochemical method for lysozyme assay in which the recently developed laser nephelometer is used. The sensitivity so achieved is at least comparable to that of the lysoplate method, and in some circumstances better. Results obtained by the lysoplate assay and the nephelometric assay correlate well. Among the advantages of our method are easier handling of larger numbers of samples, quicker results, and the possibility of assaying enzymatically inactive forms of the enzyme.

Animals↗
PubMed1977

Comparison of immunoglobulin determinations in pathological sera by radial immunodiffusion and laser nephelometry.

Immunoglobulins G, A, and M were measured by radial immunodiffusion and by laser nephelometry in sera from 33 patients and in a preparation of purified colostral IgA. In general the results agreed for the two methods, with some exceptions attributed to the physicochemical characteristics of the immunoglobulins assayed: low-molecular-weight (monomeric) IgM gives falsely high values and IgA proteins (consisting predominantly of polymeric molecules) give falsely low values when assayed by radial immunodiffusion. Results from laser nephelometry apparently are not affected by the molecular-size characteristics of the proteins assayed.

Humans↗
PubMed1976

Platelet lipoproteins. A comparative study with serum lipoproteins.

The nature of human platelet lipoproteins was studied in two series of experiments. In the first series, whole platelets were utilized for extraction of lipoproteins by three different methods: chloroform/methanol/phenol; saline; or sucrose-gradient ultracentrifugation of platelet homogenates. By polyacrylamide gel electrophoresis we were able to demonstrate the existence of lipoprotein in the extracts obtained by the last two methods. These lipoproteins were found not to share antigenic determinants with alpha and beta serum lipoproteins. The second series of experiments utilized platelets solubilized either in sodium deoxycholate or sodium dodecyl sulfate. The solubilized product was characterized by double immunodiffusion and polyacrylamide gel electrophoresis. The nonidentity between plasma and platelet lipoproteins previously demonstrated in the first series of experiments was confirmed. This nonidentity was also supported by a comparison between the apoproteins of purified serum lipoproteins and platelet proteins released after solubilization with sodium dodecyl sulfate. No identical protein fractions were found. Our results suggest that, unlike erythrocyte membrane lipoproteins, the platelet lipoproteins are structurally different from plasma lipoproteins.

Blood Platelets↗