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Query: UMLS:C0019163 (hepatitis B)
 38,309 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Hepatitis B surface antigen (HBSAg) adsorbed from sera onto colloidal silica could be completely eluted through the use of 0.25% sodium deoxycholate in 0.01 M borax, pH 9.3, at 56 degrees C. The HBSAg recovered in the eluate represented 100% of that present in the original serum, and it was contaminated by only trace amounts of serum proteins (in decreasing amounts: beta-lipoprotein, immunoglobulin G, albumin). This preliminary step greatly facilitates purification of large amounts of HBSAg and provides small volumes of highly concentrated material for subsequent purification by density gradient centrifugation.
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PMID:Optimal conditions for elution of hepatitis B antigen after absorption onto colloidal silica. 0 23

Controlled pore glass (CPG) adsorbs hepatitis B surface antigen (HBsAg) from whole plasma with a high degree of specificity. The resultant complex is stable at acid pH and in the presence of high concentrations of sodium thiocyanate. The adsorbed HBsAg is qualitatively and quantitatively similar to the soluble material in its ability to bind antibodies to HBsAg (anti-HBs). The HBsAg in 1 ml of strongly reactive plasma is adsorbed by 100 mg of CPG, which can then specifically bind 32,000 passive hemagglutination units of anti-HBs. Bound antibody can be eluted in 77% yield by acid or by chaotropic ions and the CPG-HBsAg complex can be reused in further adsorption-elution cycles. Antibody to HBsAg can be purified 144-fold in a single step by using this technique. The preparation of monospecific subtyping reagents for HBsAg and of immunochemically purified anti-HBs is described.
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PMID:A novel immunoadsorbent: use for the preparation of monospecific antibodies to the hepatitis B antigen. 2 34

Purified preparations of hepatitis B surface antigen (HBsAg) were solubilized with sodium dodecyl sulfate and urea under reducing conditions and subsequently fractionated by preparative sodium dodecyl sulfate-urea polyacrylamide gel electrophoresis (PAGE). Pools of the individual fractions eluted from the preparative PAGE were concentrated and purified further by analytical PAGE. Five purified polypeptides were isolated from HBsAg, types adw and ayw, with molecular weights of 19,000, 24,000, 27,000, 35,000, and 40,000. Each preparations was emulsified in Freund complete adjuvant and injected into guinea pigs. Antibody to each HBsAg type was measured by radioimmunoassay. The 19,000 molecular weight polypeptide derived from ayw particles and the 27,000 molecular weight subunit obtained from both types failed to elicit an antibody response. The other three polypeptides derived from the ayw particles elicited group-specific antibody responses. Similar group-specific reactivities were observed in the testing of anti-adw 35,000 and anti-adw 40,000 molecular weight polypeptide sera. However, guinea pigs immunized with the 19,000 and the 24,000 molecular weight polypeptides of the adw type produced antibody that reacted preferentially with adw particles. This indicates that either these subunits carry predominately d determinants or that, because of the low levels of material used for inoculation, no immune response or an undetectable one was elicited to the a or w components.
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PMID:Production of antibody to individual polypeptides derived from purified hepatitis B surface antigen. 5 Oct 98

The ultrastructural study of liver tissues from 38 patients with type B viral hepatitis consistently showed the presence of hepatitis B core antigen of 21-25 nm size in the liver cell nuclei and to a lesser extent in the cytoplasm. This finding and the demonstration of the tubular form of hepatitis B surface antigen in the proliferative degranulated endoplasmic reticulum constituted the etiologic criterion for the diagnosis of the disease. The double-shelled Dane-like particles were frequently found in association with the tubular form of the surface antigen. The core particles were found in the protoplasmic processes of hepatocytes and this correlated with the immunofluorescent microscopic findings that the antigen may be shed into circulation with the protoplasm. The core antigen was found to resist digestion by various enzymes such as protease, DNase, RNase, phospholipase C, lipase, lysozyme, diastase, neuraminidase and hyaluronidase, all of which did not destroy the immunoreactivity as demonstrated by immunoelectron and immunofluorescent microscopy. Similarly, sodium dodecyl sulfate, Tween 80 and mercaptoethanol also had no effect. The formalin-fixed paraffin-embedded liver tissue sections could be treated with protease to facilitate the immunofluorescent staining for the core antigen in tissue.
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PMID:Structural and immunoreactive characteristics of hepatitis B core antigen. 5 6

The PLC/PRF/5 cell line derived from a human hepatoma produces hepatitis B surface antigen (HBsAg) in 22-nm particles of the same buoyant density as those found in the serum of infected patients. The HBsAg particles from this cell line were labeled with [35S]methionine and purified, and the polypeptides were compared by sodium dodecyl sulfate-polyacrylamide gel electrophoresis with those of serum-derived particles. The two major polypeptides of serum-derived HBsAg particles (p20 and p23) were found in the same relative amounts in the particles from the cell line. The three smallest of the five minor components observed in HBsAg particles from serum were present in particles from the cell line. These polypeptides (p31, p36, and p43), as well as p20 and p23, were precipitated with anti-HBs-containing serum. The two largest polypeptides of serum particles (p49 and p66) were not detected in particles from these cells. When the PLC/PRF/5 HBsAg particles were radiolabeled with tritiated sugars, p23, and not p20, was found to contain radioactivity, indicating that the pattern of polypeptide glycosylation is similar to that of serum HBsAg. None of the other possible gene products of hepatitis B virus was detected in the PLC/PRF/5-derived HBsAg particles, in the cells, or in the cell supernatants.
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PMID:Polypeptides of hepatitis B virus surface antigen produced by a hepatoma cell line. 9 75

Three glycoproteins of intact hepatitis B surface antigen (HBsAg) with mol. wt. of 32 000, 30 000 and 28 000 respectively were identified by reaction with 125I-concanavalin A (Con A) after separation by sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE). The antigen was effectively disrupted with Triton X-100 to produce a structure with a sedimentation coefficient of 3.9S. Affinity chromatography of disrupted HBsAg using concanavalin A-Sepharose 4B (Con A-Sepharose) resulted in two fractions. The first contained material which did not bind to the lectin and consisted of a single polypeptide of mol. wt. 64 000. Further studies revealed this component to be serologically identical to serum albumin and to lack any affinity for antibody to HBsAg. A comparison of the tryptic peptide map of this polypeptide with that of purified serum albumin demonstrated identical amino-acid sequences. The second fraction contained material which bound to Con A and contained two polypeptides with mol. wt. of 28000 and 23000 respectively. HBsAg reactivity was associated with this fraction. This procedure allows the prepartion of HBsAg sub-units in milligram quantities for further immunological studies.
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PMID:Analysis of hepatitis B surface antigen components solubilized with Triton X-100. 9 17

N-alpha-Cocoyl-L-arginine ethyl ester, DL-pyroglutamic acid salt (CAE), exhibited a strong inactivating effect on hepatitis B surface antigen. Concentrations of CAE required for 50 and 100% inactivation of the antigen were 0.01 to 0.025% and 0.025 to 0.05% respectively. CAE completely inactivated hepatitis B surface antigen at the lowest concentration compared with various compounds including about 500 amino acid derivatives, sodium hypochlorite, 2,4,4'-trichloro-2'-hydroxydiphenyl ether, and some detergents. Furthermore, CAE inactivated vaccinia virus, herpes simplex virus, and influenza virus, whereas poliovirus was not inactivated at all. The results suggest that the inactivating effects of CAE are related to interaction with lipid-containing viral envelopes.
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PMID:N-alpha-Cocoyl-L-arginine ethyl ester, DL-pyroglutamic acid salt, as an inactivator of hepatitis B surface antigen. 22 95

Hepatitis B virus surface antigen (HBsAg) could be studied until recently only by isolating it from the blood of carriers, thus making incorporation of radioactive precursors into this protein(s) impossible. The isolation of a cell line producing HBsAg [Alexander et al, 1978] has eliminated this obstacle. The cell line was therefore used for labeling HBsAg either with 35S-methionine or with 35S-cystine. HBsAg was purified by pelleting the component and by isopycnic centrifugation in CsCl gradients. HBsAg-positive fractions (as determined by solid-phase radioimmunoassay) were isolated from the gradients and analyzed in sodium dodecyl sulfate-containing polyacrylamide gels. It was found that although HBsAg contains substantial amounts of 35S-cystine, very little 35S-methionine was incorporated into this protein. In contrast, both labels were found in other structures having a buoyant density of about 1.3 gm/cm3 in CsCl. It was concluded that HBsAg is very low in methionine, and therefore this amino acid should not be used for labeling HBsAg in cells or in a cell-free system. Analysis of 35S-cystine-labeled HBsAg-positive material (buoyant density about 1.2 gm/cm3 in CsCl) revealed five proteins with molecular weights in the range of 48,000-82,000.
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PMID:Labeling of hepatitis B virus surface antigen (HBsAg) synthesized in a HBsAg-producing hepatoma cell line. 23 37

A study of two different virus types after elution from immunosorbent columns by sodium thiocyanate has shown that virus degradation occurs. The two virus types studied were hepatitis B and rotavirus. Hepatitis B antigen (HBAg) was only slowly degraded and retained many of its morphological features, although in an altered form; rotavirus was highly sensitive to the chaotropic agent, losing both its viability and its morphological integrity. During the process of disassembly a previously undetected inner component of rotavirus could be visualised, which was termed the "core."
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PMID:The effect of sodium thiocyanate on virus structure. 23 43

A finger prick-swab method of blood specimen collection was qualitatively and quantitatively compared with the conventional venipuncture method for HBsAg and anti-HBs determinations by radioimmunoassay (RIA). The new method consisted of pricking the finger, collecting 0.1-0.2 ml of blood with a cotton-wool swab, and eluting the swab in 1 ml of 1% bovine albumin in saline containing 0.1% sodium azide. Using chimpanzees seropositive for HBsAg or anti-HBs, comparisons were made of RIA results of: (a) whole blood, haemolysed blood, serum, and plasma; (b) paired finger prick samples and serum; (c) dilutions of finger prick samples and serum; and (d) different volumes of blood on swabs. Field studies were carried out at two institutions where hepatitis B was hyperendemic to compare results from paired finger prick and serum specimens assayed by the RIA and haemagglutination techniques. The laboratory studies showed that swab RIA values for anti-HBs were significantly lower than serum values and that for HBsAg, swab values were significantly higher than serum values. In HBsAg tests, the field studies showed 100% agreement between the two methods; in anti-HBs tests, the finger prick method showed 85% agreement with positive sera. Because of the logistics of collecting and processing blood serum, the finger prick-swab technique may be a valuable aid in large-scale seroepidemiological surveys for hepatitis B.
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PMID:Evaluation of a finger prick blood collection method for the seroepidemiology of hepatitis B. 31 Jul 21


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