ABSTRACT
Two peptides, IFN-(125-129) (RITLY-I) and [Arg7]IFN-(125-131) (RITLYLR-II), belonging to the putative immunologically active region of interferon alpha A (IFN) were synthesised by the solid-phase method. Both peptides suppress the delayed-type hypersensitivity reaction in vivo as assayed in mice. The peptide (II) either suppresses (0.01-0.1 mg/kg) or stimulates (approximately 1.0 mg/kg) antibody production in mice in response to sheep red blood cells.
Subject(s)
Interferon Type I/chemical synthesis , Peptide Fragments/chemical synthesis , Amino Acids , Animals , Antibody Formation , Humans , Interferon Type I/genetics , Interferon Type I/pharmacology , Mice , Mutation , Peptide Fragments/genetics , Peptide Fragments/pharmacologyABSTRACT
A study was made of the effect of the low-molecular neuropeptides, leu- and met-enkephalins, thyroliberin (TRH), the C-end tripeptides, gastrin (MAF) and oxytocin (MIF) on the content of biogenic monoamines and their metabolites and on the production of humoral antibodies to sheep red blood cells. The action of the peptides enumerated was compared to that of the peptide immunostimulant, tuftsin. All the peptides (upon intraventricular administration) with the exception of tuftsin affect the content of brain biogenic monoamines or their metabolites. Moreover, upon intravenous injection the neuropeptides under study except met-enkephalin exert a modulating action on the immune response pattern and intensity Leu-enkephalin, MIF and MAF have immunostimulant activity similar to tuftsin. TRH given in high doses (100 and 150 mg/kg) provokes almost a two-fold decrease in the antibody titer. This peptide has an immunosuppressant effect when administered both intravenously and intracisternally. It is suggested that neuro- and immunomodulator effects have much in common at the level of cell receptors.
Subject(s)
Adjuvants, Immunologic/pharmacology , Nerve Tissue Proteins/pharmacology , Neurotransmitter Agents/pharmacology , Animals , Biogenic Amines/metabolism , Brain/drug effects , Brain/metabolism , Dose-Response Relationship, Immunologic , Enkephalins/immunology , Enkephalins/pharmacology , Gastrins/immunology , Gastrins/pharmacology , Hemagglutinins/analysis , Mice , Mice, Inbred BALB C , Molecular Weight , Nerve Tissue Proteins/immunology , Neurotransmitter Agents/immunology , Oxytocin/immunology , Oxytocin/pharmacology , Rats , Rats, Inbred Strains , Thyrotropin-Releasing Hormone/immunology , Thyrotropin-Releasing Hormone/pharmacologyABSTRACT
One of the pressing tasks in the study of local nonsusceptibility to infectious diseases and immunochemical analysis of the external secretion is recording of the level of various forms of the secretory IgA (SIgA) and of the secretory component (SC) in various biological fluids. Indication and measurment of the concentrations of the mentioned proteins encounter serious difficulties caused by heterogeneity of their molecular forms. It was shown that the antisera to the whole molecule of SIgA and SC are of no use. On the basis of a new method of purification of free SC and technology of preparation of monospecific antisera capable of separation of SIgA and free SC there were obtained diagnostic antisera for the quantitative recording and differentiation of various forms of IgA and SC in biological fluids. A reliable measurement of the SIgA and SC concentration in some external secretion was carried out with the aid of the mentioned preparations without any complicated chromatographic experiments.
Subject(s)
Colostrum/immunology , Immune Sera/isolation & purification , Immunoglobulin A, Secretory/isolation & purification , Immunoglobulin A/isolation & purification , Immunoglobulin Fragments/isolation & purification , Secretory Component/isolation & purification , Animals , Epitopes , Evaluation Studies as Topic , Female , Hemagglutination Inhibition Tests/methods , Humans , Immunodiffusion/methods , Pregnancy , Quality Control , RabbitsABSTRACT
Sera of healthy and sick persons were tested for the presence of secretory IgA (SIgA) and free secretory component (SC) SIgA was present in the blood of healthy persons in low concentrations (1.07 mg/100 mg), and free SC was absent. Infectious and somatic diseases, in which damage of the epithelial covering of the gastrointestinal and respriatory tracts was possible, were accompanied by increased blood SIgA content. There was also noted a distinct relationship between the blood SIgA concentration and the severity of infectious diseases and pneumonia supervention. In these cases the SIgA level proved to rise.
Subject(s)
Health , Immunoglobulin A, Secretory/analysis , Immunoglobulin A/analysis , Adolescent , Adult , Child , Child, Preschool , Communicable Diseases/immunology , Free Radicals , Hemagglutination Inhibition Tests , Humans , Infant , Infant, Newborn , Neoplasms/immunology , Secretory Component/analysisABSTRACT
In comparison with the radial immunodiffusion method, the sensitivity of the indirect hemagglutination test in determining the concentration of immunoglobulins G, M and A in various biological substrates (blood serum, saliva, cerebrospinal fluid, feces) was 35--100 greater. Under the action of proteolytic enzymes immunoglobulin fragmentation led to increase in the concentration of the Ig indices (according to the data of radial immunodiffusion) and produced no effect on the indices of the indirect hemagglutination test; The latter should be used to determine the immunoglobulins in the external secretions characterized by a low content of the given proteins and a marked probability of their proteolytic splitting. In assessing the results of the indirect hemagglutination test it should be remembered that it was less precise and less reproducible than the radial immunodiffusion method.
