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P Musiani

Publications and source records attributed to P Musiani.

At least 145 records · Page 8Linked to original sources

Echinococcus granulosus: specific quantification of the two most immunoreactive antigens in hydatid fluids.

Preparations of the two most immunoreactive Echinococcus granulosus antigens (antigens 4 and 5) from sheep hydatid fluid, purified by a simplified method, and monospecific antisera against antigens 4 and 5, prepared by a new procedure, were used to measure the antigenic concentrations of antigens 4 and 5 in swine, sheep, and human hydatid fluids from pulmonary or hepatic cysts. Two bovine samples and two commercial preparations were also tested. The concentration of both antigens was significantly higher in sheep and human hydatid fluids than in swine hydatid fluid. The antigenic content of the two bovine samples and of the two commercial preparations was below the sensitivity level of the method employed. Independently of the species tested, the amount of Echinococcus antigens was greater in hepatic than in pulmonary cysts. The ratio between the concentrations of antigens 4 and 5 was constant at about 1:10 in the samples from various organs and from different species. When there were enough samples for statistical analysis a linear correlation was found between the contents of these two antigenic components but there was none between the amounts of proteins and the antigenic concentrations in the single cysts. Sheep hydatid fluid must therefore be considered the best source of antigenic material for diagnostic purposes even though in human cysts the antigenic fraction is less contaminated by serum proteins. We describe a reliable method of standardising antigenic material for the immunodiagnosis of hydatid disease.

Animals↗

Alpha-1-antitrypsin phenotypes in newborns from Central and Southern Italy.

The results of Pi typing on 500 infants from Central and Southern Italy are reported. Phenotype determinations were performed on umbilical cord serum. We observed nine different phenotypes; each of these is present in other European populations. The frequencies of the Pi alleles in our group were found to be, on the whole, comparable to those found in other populations widely separated geographically. However, the frequency of the Pi S gene in our sample (0.0670) was greater than that observed in Northern and Central European and American groups. Our Pi S frequency was similar to that found in a French group and lower than that of Spanish and Portuguese groups. Our data thus confirm the higher Pi S gene frequency in Latin populations.

Alleles↗

Echinococcus granulosus: identification of subunits of the major antigens.

This paper describes a procedure for obtaining the two "major" Echinococcus granulosa antigens (antigens 4 and 5) from sheep hydatid fluid. Purified antigen 4 (m.w. 400,000 and over) and antigens 5 (m.w. 150,000) were separated in order to identify molecular subunits of each. SDS 12.5% polyacrylamide gel electrophoresis of antigen 4 gave a single band for which a m.w. of 67,000 was calculated. When 5% 2-mercaptoethanol was added to the antigen 4 preparation, SDS 12.5% polyacrylamide gel electrophoresis gave two bands (m.w. 47,000 and 20,000). SDS 12.5% polyacrylamide electrophoresis of antigen 5, with or without 2-mercaptoethanol, gave at least three bands with m.w. ranging from 10,500 to 20,000. Low m.w. subunits of both antigens were eluted in a single peak from a preparatory SDS 7.5% acrylamide gel electrophoresis; these subunits were found to be immunogenic and antigenic.

Animals↗

Isolation, chemical, and physical properties of alpha-1-antitrypsin.

A method of isolation of alpha-1-antitrypsin (alpha-1-AT) in good yield from normal human plasma is described. A key step was affinity chromatography employing an antiserum which had been depleted of alpha-1-AT antibodies. The final preparations were homogeneous by immunological and physicochemical criteria. The specific activity of the purified alpha-1-AT was 0.363 mg of active bovine trypsin inhibited per 1.0 mg of inhibitor. Polyacrylamide gel patterns at both alkaline and acid pH of highly pure preparations frequently, but not invariably, showed multiple hands. Molecular weight studies by sedimentation equilibrium ultracentrifugation in aqueous buffer and in 6 M guanidine as well as sodium dodecyl sulfate polyacrylamide gel electrophoresis suggest that alpha-1-AT is a single polypeptide chain having a molecular weight of 49,500. Other physical and chemical properties of the inhibitor are described. A limited N-terminal sequence (Glu-Asp-Pro-Gln-Gly-Asx-Ala-Ala) was obtained. It was found that alpha-1-AT easily forms polymers and higher aggregates when exposed to denaturing agents such as 8 M urea and 6 M guanidine. The results suggest that aggregation is determined by both covalent and noncovalent forces.

Amino Acid Sequence↗

Isolation of the most immunoreactive antigenes of echinococcus granulosus from sheep hydatid fluid.

This paper describes a simplified procedure for obtaining purified Echinococcus granulosus antigens from sheep hydatid fluid by using affinity chromatography on concanavalin A-Sepharose. The presence of two "major" antigens (4 and 5) was confirmed. Antigen 5 was isolated by preparative polyacrylamide gel electrophoresis. Antigen 4, eluted by diffusion from the gel, was seen to be "contaminated" by antigen 5 and was isolated by using anti-5 Sepharose-linked serum. These two major antigens were then tested separately against the sera of hydatidosis patients by using very simple immunolgic tests. The best results were obtained in passive hemagglutination with antigen 4. Antigen 4 is the most immunoreactive parasitic antigen; antibodies against it were found in the sera of all hydatidosis patients showing positive reaction. Apart from the direct use of this antigen in serologic tests, it appears possible to standarize the most frequently used and commerically available antigenic materials by titrating this component.

Animals↗