摘要:

The aim of this study was to investigate whether theex vivowhole blood culture (WBC) assay system can be used to detect pyrogens in blood from patients with symptoms of sepsis.

ISSN:0197-1522    

DOI:10.1080/01971529909349310

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor

摘要:

The effect of pH of the blocking solution on the non-specific sorption of peroxidase conjugates to the 0.63-cm formylated polystyrene beads was studied. Anti-G-HRP and BSA-HRP sorption was shown to dramatically depend on pH of blocking protein solutions and was minimum at pH=pI. Sorption of G-HRP weakly depended on pH of the blocking buffer. the blocking efficiency of proteins on unmodified beads, as well as of Tween-20 on formylated beads appeared to be pH independent. the optimized blocking step resulted in a multiple decrease in the non-specific sorption of conjugates on formylated beads.

ISSN:0197-1522    

DOI:10.1080/01971529909349311

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor

摘要:

Cytokines occur in biological systems at low levels of concentration, therefore assays developed to measure them must be very sensitive. Enzyme linked immunosorbent assays (ELISA's) developed using manufacturers recommended end points can detect cytokines to picogram levels but the lower parts of their standard curves can be unreliable. in this study the relative merits of different substrate systems - 2,2′-azinobis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) and 2 forms of tetramethyl benzidine (TMB), were investigated with regard to assay sensitivity. Further, a signal amplification method involving biotinylated tyramine has been used to increase the absorbance signal and thus the assay sensitivity and to achieve a sigmoidal standard curve. the amplified assay approach has been applied successfully to achieve more sensitive detection of TNF-α and improve the sensitivity of assays for a wide range of other cytokines. the optimised amplification method is the same for all the cytokine ELISA's performed in this work and this enables them to be performed simultaneously to allow multiple cytokine analysis of one sample.

ISSN:0197-1522    

DOI:10.1080/01971529909349312

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor

摘要:

Antisera were raised in rabbits against two mouse monoclonal anti-porcine growth hormone (pGH) antibodies. Anti-idiotypic antibodies were isolated from rabbit sera by successive passage over immunoadsorbent columns of normal mouse 1g (mIg), followed by the specific immunizing monoclonal and elution from the latter. Enzyme linked immunoadsorbent assay (ELISA) for anti-idiotype and free idiotype were established. While showing specificity for their respective inducing monoclonals, anti-idiotypes also cross reacted in varying degrees with other anti-pGH monoclonals regardless of specificity differences between the antibodies, demonstrating the presence of a cross-reactive idiotype.

ISSN:0197-1522    

DOI:10.1080/01971529909349313

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor

摘要:

Hybridoma cells were prepared by immunizing mice with carboxylic derivatives of atrazine conjugate to bovine serum albumin. After the screening of culture supernatant of hybridomas, five cell lines producing monoclonal antibodies were established and 1.8-5.3 ml of ascitic fluid per mouse was obtained from each cell line. the protein A affinity purification yielded 0.35-0.65 mg per ml of ascitic fluid from each cell line. the characterization studies in terms of sensitivitiy and specificity indicate that MAb 2F9 and MAb 4B9 showed the best responses with atrazine and its group of ametryne and cyanazine, using microtiter plate coated with simazine derivative of 6-amino hexanoic acid; no cross-reactivity was shown with simazine and cyanuric chloride.

ISSN:0197-1522    

DOI:10.1080/01971529909349314

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor

摘要:

Purified E. coli endotoxin, Gram negative bacteria and Gram positive bacteria induce IL-6 secretion by whole blood cultures (WBC's). Polymyxin B at concentrations greater than 2 U/ml completely inhibits IL-6 secretion caused by 10 EU/ml of endotoxin. Polymyxin B has no effect on IL-6 secretion by WBC's in the absence of endotoxin. the inhibition of endotoxin induced IL-6 secretion is Polymyxin B concentration dependent at concentrations less than 1 U/ml. IL-6 induction caused by E. coli is only partially inactivated by 8 U/ml Polymyxin B. Polymyxin B has no effect on IL-6 secretion caused by B. subtilis. Two pyrogenic batches of human serum albumin (HSA), as tested by the rabbit assay for pyrogens, were also investigated. Polymyxin B at 4 U/ml inhibits less than 40 % of IL-6 secretion caused by these pyrogenic HSA batches. All the endotoxin activity in HSA samples spiked with purified endotoxin is inhibited by Polymyxin B indicating that HSA does not protect endotoxin against Polymyxin B inhibition. These results indicate that the pyrogenicity of these HSA batches are caused by Polymyxin B inhibitable and non-inhibitable fractions.

ISSN:0197-1522    

DOI:10.1080/01971529909349315

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor

摘要:

A direct sandwich enzyme-linked immunosorbent assay (ELISA), employing affinity purified antivenom antibodies specifically recognizing the homologous venom, was developed for species-specific detection of bothropic venom. the method is based on a two-step affinity purification of the specific antibodies. A species monovalent antivenom is adsorbed onto a venom adsorbent containing heterologous venoms from theBothrops, CrotalusandLachesisgenera. the species-specific antibodies obtained, are then adsorbed onto a second venom adsorbent containing only the homologous venom for the removal of non antivenom antibodies. Venom concentrations of 0.1 and 1,000 ng/ml were specifically identified forBothrops jararacussuandB. alternatusvenom respectively.

ISSN:0197-1522    

DOI:10.1080/01971529909349316

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor