Direct visualization of redistribution and capping of fluorescent gangliosides on lymphocytes
نویسندگان
چکیده
Fluorescent derivatives of gangliosides were prepared by oxidizing the sialyl residues to aldehydes and reacting them with fluorescent hydrazides. When rhodaminyl gangliosides were incubated with lymphocytes, the cells incorporated them in a time- and temperature-dependent manner. Initially, the gangliosides were evenly distributed on the cell surface but were redistributed into patches and caps by antirhodamine antibodies. When the cells were then stained with a second antibody or protein A labeled with fluorescein, the fluorescein stain revealed the coincident movement of both the gangliosides and the antirhodamine antibodies. When the cells were treated with both rhodamine and Lucifer yellow CH-labeled gangliosides, the antirhodamine antibodies induced patching and capping of both fluorescent gangliosides but had no effect on cells incubated only with Lucifer yellow CH-labeled gangliosides. In addition, capping was observed on cells exposed to cholera toxin, antitoxin antibodies, and rhodamine-labeled protein A, indirectly showing the redistribution of endogenous ganglioside GM1, the cholera toxin receptor. By incorporating Lucifer yellow CH-labeled GM1 into the cells and inducing capping as above, we were able to demonstrate directly the coordinate redistribution of the fluorescent GM1 and the toxin. When the lymphocytes were stained first with Lucifer yellow CH-labeled exogenous ganglioside GM3, which is not a toxin receptor, there was co-capping of endogenous GM1 (rhodamine) and exogenous GM3 (Lucifer yellow CH). These results suggest that gangliosides may self-associate in the plasma membrane which may explain the basis for ganglioside redistribution and capping.
منابع مشابه
Blocking and Redistribution ("capping") of Antigen Receptors on T and B Lymphocytes by Anti-immunoglobulin Antibody
Antigen-binding T and B lymphocytes were studied by combined autoradiography and immunofluorescence; mouse spleen lymphocytes binding the antigens, [(125)I]MSH or [(125)I]TIGAL, were incubated with rhodamine-labeled anti-Ig reagents or with a rhodamine-labeled IgG fraction of anti-theta serum. B cells were identified as Ig+ or theta-, T cells as Ig- or theta+. It was found that: (a) 20% (1-2 mo...
متن کاملTwo distinct mechanisms for redistribution of lymphocyte surface macromolecules. I. Relationship to cytoplasmic myosin
A detailed kinetic analysis of the distribution of cytoplasmic myosin during the capping of various lymphocytic surface molecules revealed two distinct capping mechanisms. (a) Some cell surface molecules, including immunoglobulin, Fc receptor, and thymus leukemia antigen, all cap spontaneously in a small fraction of lymphocytes during locomotion. Cytoplasmic myosin becomes concentrated in the c...
متن کاملVisualization of Concanavalin A-binding Sites with Scanning Electron Microscopy
Plant lectins, because they bind to specific carbohydrate moieties, can be used to investigate the glyco-components of the cell surface. When considering the distribution, number, or mobility of lectin-binding sites, a distinction must be made between a natural distribution and a redistribution induced by binding with multivalent ligands (2, 4, 5, 8, 14, 15). In some cell types the induced redi...
متن کاملCapping of cholera toxin-ganglioside GM1 complexes on mouse lymphocytes is accompanied by co-capping of alpha-actinin
We used cholera toxin, which binds exclusively and with a high affinity to the ganglioside GM1, as a probe to investigate the distribution of this glycolipid on the surface of mouse lymphocytes. When lymphocytes are incubated with cholera toxin (or its B subunit) and then sequentially with horse anti-toxin and FITC-swine anti-horse Ig at 37 degrees C, the cholera toxin-ganglioside GM1 complex i...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید
ثبت ناماگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید
ورودعنوان ژورنال:
- The Journal of Cell Biology
دوره 99 شماره
صفحات -
تاریخ انتشار 1984