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1.
The biological activities of Nerve Growth Factor (NGF) purified from bovine seminal plasma have been compared with those of NGF from mouse submandibular glands in a variety of systems: maintenance of survival in vitro and stimulation of nerve fibre outgrowth from sensory, sympathetic and parasympathetic neurons of the embryonic chick; maintenance of survival in vitro, stimulation of nerve fibre outgrowth and specific induction of tyrosine hydroxylase in neonatal rat sympathetic neurons; stimulation of nerve fibre outgrowth and cellular hypertrophy and specific induction of choline acetyltransferase in pheochromocytoma PC12 cells; induction of tyrosine hydroxylase in bovine adrenal medullary cells; and stimulation of nerve fibre outgrowth from expiants of goldfish retinae. In all cases, the two NGFs had the same effects qualitatively and quantitatively, and with identical dose-dependencies. The results indicate that the wide range of biological effects and target cells delineated in detail for mouse NGF can justifiably be attributed to other NGF proteins, and that they are not exclusively restricted to the mouse NGF molecule. Furthermore, as bovine NGF is free of the renin contaminants so difficult to remove from mouse NGF, the above biological activities can truly be assigned to the NGF molecule.Immunologically, however, mouse and bovine NGFs differ substantially. This is demonstrated by the relatively poor ability of antisera against bovine NGF to inhibit the activity of mouse NGF in vitro, and by the incomplete nature of the immunosympathectomy caused in rats by treatment with antisera to bovine NGF, in contrast to the extensive immunosympathectomy caused in these animals by the administration of comparable quantities of antisera against mouse NGF.Clearly, the biochemical features of the NGF molecules responsible for their biological effectiveness and for their predominant antigenic properties are different.  相似文献   

2.
We studied physical development, behavioral characteristics, and learning capacity in the off-spring of mice immunized with nerve growth factor and bovine serum albumin. High titer of antibodies to these factors in the blood of pregnant females determines high levels of these antibodies in the blood of their pups. These changes modulate physical development, behavior, and learning capacity of rat pups. The effects of these antibodies differed in the strength and directionality. Antibodies to nerve growth factor more markedly retarded physical development, reduced learning capacity, and considerably increased pain thresholds in animals. Translated fromByulleten’ Eksperimental’noi Biologii i Meditsiny, Vol. 138, No. 7, pp. 98–100, July, 2004  相似文献   

3.
A novel technique for establishing short term clones of antigen- or mitogen-activated splenic B lymphocytes is described. Spleen cells are plated onto the surface of filter paper discs and subsequently stimulated by antigen or mitogen in situ; activated B cells proliferate and differentiate into pure colonies of cells analogous to bacterial colonies growing on agar. These colonies of lymphocytes may be characterized in a series of replica hemolytic-plaque, autoradiographic, or immunoenzyme assays making possible a full characterization of the frequency of secreted idiotopes and paratopes and of the cells that produce them. Colony induction by either antigen or mitogen occurs under identical conditions, thus a rigorous comparison between the mitogen-selected and antigen-selected antibody repertoires may be made.  相似文献   

4.
A simple and rapid technique to measure bovine factor VIII-related antigen has been developed which utilizes protein A-bearing staphylococci and monospecific rabbit antiserum to bovine factor VIII. Staphylococci coated with a specific antibody agglutinate when they are mixed with the specific antigen. We have used an aggregometer to detect an quantitate the agglutination of the antibody-coated staphylococci. The assay has been optimized with respect to amount of antiserum needed for coating staphylococci, concentration of antibody-coated staphylococci, pH and ionic strength of the assay system, and stirring speed of the aggregometer. The staphylococcal co-agglutination assay as monitored by an aggregometer is at least 10 times more sensitive than the conventional slide agglutination method, and can detect as little as 0.1 microgram/ml of factor VIII antigen. It however, cannot be used to quantitate factor VIII-related antigen in plasma, since plasma contains some components which can non-specifically agglutinate staphylococci.  相似文献   

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