Immunoglobulins on the surface of sheep lymphocytes. ii. class, size and fate during incubation of lymphocytes at 37 °c
| Autor: | P. L. Ey |
|---|---|
| Rok vydání: | 1973 |
| Předmět: |
Globulin
Lymphocyte Immunology Immunoglobulins Antibodies Iodine Radioisotopes Cell membrane Immunoglobulin Fab Fragments chemistry.chemical_compound medicine Animals Immunology and Allergy Centrifugation Lymphocytes Incubation Cells Cultured Antilymphocyte Serum Sheep biology Immune Sera Cell Membrane Precipitin Tests medicine.anatomical_structure Biochemistry chemistry biology.protein Autoradiography Sodium azide Rabbits Azide Antibody Ultracentrifugation |
| Zdroj: | European Journal of Immunology. 3:402-409 |
| ISSN: | 1521-4141 0014-2980 |
| DOI: | 10.1002/eji.1830030706 |
| Popis: | Sheep lymphocytes possessing surface Ig were labeled with 125I-labeled anti-Ig antibodies. The radioactive complexes thus formed were dissolved from the cell membrane by treatment with the detergent Nonidet-P40 and their molecular sizes estimated by sedimentation centrifugation. IgG and IgM (20–40 % as 19 S IgM) were shown to be present on the cell surface. Cells labeled with anti-Ig antibodies and incubated at 37 °C lost 30–40 % of their radioactivity within 30–45 min, after which time the rate of loss decreased. By 3–4 h, approximately 50 % had been released and loss had almost stopped. Label associated with surface-bound anti-sheep lymphocyte globulin was also lost rapidly (20–30 % in 30 min), but unlike anti-Ig antibodies, no further loss occurred. Anti-Ig complexes retained by labeled cells during incubation at 37 °C were steadily degraded to a 3–4 S component. Sodium azide (0.015 M) significantly reduced the rate at which this degradation occurred (e.g. inhibition relative to degradation in the absence of azide was 94 % after 2 h and 67 % after 4 h incubation, respectively). When unlabeled lymphocytes were incubated at 37 °C for up to 20 h and then reacted with labeled anti-Ig, the following was observed. The proportions of lymphocytes able to bind anti-γ or anti-μ-chain antibody (as judged by autoradiography) decreased from 17 % to 3 % and 28 % to 18 %, respectively, during 20 h incubation. From measurements of Ig released during incubation, it was concluded that most of the IgG initially on cells binding anti-γ-chain antibody was probably cytophilic. IgM initially on the surface of cells binding anti-μ-chain antibody seemed to be released and replaced by the cells, although a small proportion may have been cytophilic. |
| Databáze: | OpenAIRE |
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