Production of antibodies to amanitins as the basis for their radioimmunoassay

Summary The production of antibodies against amanitins is described. By means of these antibodies, a radioimmunoassay was developed which allows detection of as little as 0.5 ng of amanitins in 1 ml of serum. By this method, the clearance of α-amanitin from the blood of poisoned mice was measured. Acknowledgments. We thank ProfessorT. Wieland and Dr.H. Faulstich (Heidelberg) for their generous gift of β-amanitin and [³H]O-methyl-demethyl-γ-amanitin. This work was supported by grants from C.N.R., Rome.     

9,10-Dihydroergotamine: Production of antibodies and radioimmunoassay

Summary Antibodies against 9,10-dihydroergotamine (DHE) were produced by immunizing rabbits with a conjugate of 6-nor-6-carboxymethyl-9,10-dihydroergotamine and bovine serum albumin. A highly specific and sensitive radioimmunoassay for DHE has been developed.We are greatly indebted to Dr.T. Fehr for the synthesis of 6-nor-6-carboxymethyl-9,10-dihydroergotamine, and to Dr.E. Schreier for providing us with 9,10-dihydroergotamine-[13-³H]-base of high specific activity.     

Vitamin A antibodies: Application to radioimmunoassay

Summary A radioimmunoassay for serum vitamin A is described which can detect as little as 1 ng of retinol. The statistical characteristics of this assay are presented and its use in a nutritional experiment is discussed.This work was supported by United States Public Health Service grant 2 RO1 AM19716.     

Production of monoclonal anti-Schistosoma mansoni antibodies. Preliminary study of their biological activities]

Monoclonal antibodies against Schistosoma mansoni have been produced by fusion of splenic lymphocytes from S. mansoni infected Rats and P3-X63-Ag8 BALB/c cells. In vitro and in vivo studies of the biological activities of these antibodies have led to the identification of IgE antibodies with a high reaginic activity and antibodies which in a complement dependent or eosinophil dependent system were shown to have a marked cytotoxicity for schistosomula in vitro. This methodology seems to open new perspectives for the study of antibody function in immunity against parasites as well as for the isolation of the corresponding target antigens.     

Production of antibodies against bradykinin.

High-titer antibodies against bradykinin were raised in rabbits. 2 different conjugates of bradykinin were used for immunization: bradykinin coupled to human serum albumin via 1,5-difluoro-2,4-dinitrobenzene and bradykinin coupled to edestin via 1-ethyl-3(3-dimethyl-aminopropyl)-carbodiimide. The sensitivity of the radioimmunoassay method is in the range of 1-50 pg of bradykinin. Cross-reaction of anti-bradykinin antisera occurred with kallidin and met-lys-bradykinin.     

Enhanced inhibition of RNA synthesis by amanitins in in vitro cultured cells.

The inhibition of RNA synthesis by alpha-amanitin on in vitro cultured cells is very slow. The action of various analogueoreover pretreatment of cell cultures with DEAE-dextran greatly enhanced the effect of beta-amanitin.     

A possible chemical basis for the higher mutagenicity of marijuana smoke as compared to tobacco smoke.

The results of comparative anslyses of polynuclear aromatic hydrocarbons in marijuana and tobacco smoke indicate a considerably higher content of potential carcinogens in the former. A model experiment involving delta9-tetrahydrocannabinol suggests that the pyrolysis products of cannabinoids are major contributors to the polynuclear aromatic hydrocarbons.     

Dissociation constants of the complexes between RNA-polymerase II and amanitins

Riassunto Sono state calcolate le costanti di dissociazione dei complessi fra la RNA-polimerasi II e la metil--amanitina, la -amanitina e la metil-aldoamanitina. La K _d è risultata essere 3.6×10^–9 M per la metil--amanitina e 3.2×10^–9 M per la -amanitina. La metil-aldoamanitina non si lega all'enzima.     

Production of antibodies against bradykinin

Summary High-titer antibodies against bradykinin were raised in rabbits. 2 different conjugates of bradykinin were used for immunization: bradykinin coupled to human serum albumin via 1,5-difluoro-2,4-dinitrobenzene and bradykinin coupled to edestin via 1-ethyl-3(3-dimethyl-aminopropyl)-carbodiimide. The sensitivity of the radioimmunoassay method is in the range of 1–50 pg of bradykinin. Cross-reaction of anti-bradykinin antisera occurred with kallidin and met-lysbradykinin.     

A possible chemical basis for the higher mutagenicity of marijuana smoke as compared to tobacco smoke

Summary The results of comparative analyses of polynuclear aromatic hydrocarbons in marijuana and tobacco smoke indicate a considerably higher content of potential carcinogens in the former. A model experiment involving ⁹-tetrahydrocannabinol suggests that the pyrolysis products of cannabinoids are major contributors to the polynuclear aromatic hydrocarbons.We thank Dr.John Benner and Ms.Carolyn Keene of the University of Kentucky for help with the smoking experiments. This work was supported by Grant No. R01-DA-00507-01 from the National Institute of Mental Health.     

ACTH antibodies and their use for a radio-immunoassay for ACTH

Résumé Des anticorps anti-ACTH ont été produits. Ils forment avec l'ACTH un complexe non précipitable. Ils ont servi au développement d'un test radio-immunologique de détermination de l'ACTH.     

Liposomes as immunological carriers for the preparation of antimannosyl antibodies

Antiserum was raised against an aminophenyl derivative of D-mannose grafted on to a liposomal surface. As characterized by immunodiffusion, quantitative precipitation and hapten inhibition, the antiserum was found to contain mannose specific antibodies in addition to antibodies against the aromatic phenyl group.     

Liposomes as immunological carriers for the preparation of antimannosyl antibodies

Summary Antiserum was raised against an aminophenyl derivative of D-mannose grafted on to a liposomal surface. As characterized by immunodiffucion, quantitative precipitation and hapten inhibition, the antiserum was found to contain mannose specific antibodies in addition to antibodies against the aromatic phenyl group. Acknowledgment. We would like to thank Mr S. Kumar Roy for his excellen technical assistance.     

A technical improvement in the radioimmunoassay of cyclic-AMP.

An improvement in the technique for the radioimmunoassay of cyclic-AMP, wherein ammonium sulfate precipitation is replaced with zirconyl phosphate gel, is presented. This substitution produces a more stable pellet than that obtained with ammonium sulfate. This greatly reduces a potential source of error due to pellet instability.     

Stereoselectivity of a radioimmunoassay for the insecticide S-bioallethrin

Summary The stereoselectivity of a radioimmunoassay (RIA) system using an S-bioallethrin specific antiserum was studied by observing the abilities of the 8 allethrin isomers and other selected compounds to compete with a radiolabelled S-bioallethrin tyramine derivative for antibody binding sites. The results demonstrate the feasibility of RIA as a rapid, sensitive and stereoselective residue technique for compounds difficult to analyze by classical methods.This work was supported in part by grant No. 5-R01-ES01260-02 from the National Institutes of Health.     

Stereoselectivity of a radioimmunoassay for the insecticide S-bioallethrin

The stereoselectivity of a radioimmunoassay (RIA) system using an S-bioallethrin specific antiserum was studied by observing the abilities of the 8 allethrin isomers and other selected compounds to compete with a radiolabelled S-bioallethrin tyramine derivative for antibody binding sites. The results demonstrate the feasibility of RIA as a rapid, sensitive and steroselective residue technique for compounds difficult to analyze by classical methods.     

Disruption of mitochondrial function as the basis of the trypanocidal effect of trifluoperazine on Trypanosoma cruzi.

The tricyclic anti-calmodulin drug trifluoperazine (TFP) inhibited growth and motility of epimastigotes of Trypanosoma cruzi, at concentrations lower than 100 microM, and motility and infectivity of the bloodstream trypomastigote form at 200 microM. Electron microscopy of TFP-treated epimastigotes showed that the major effect was at the mitochondrial level, with gross swelling and disorganization. The oligomycin-sensitive, mitochondrial ATPase was completely inhibited by 20 microM TFP, and the same drug concentration caused a 60% decrease in intracellular ATP content. The results suggest that the trypanocidal effect of TFP may be related more to mitochondrial damage than to the well-known anticalmodulin effect of the drug.