title: Expression of immunoglobulin synthesis in human myeloma x non-lymphoid cell heterokaryons: evidence for negative control.
abstract: Heterokaryons formed between human myeloma cells and various types of mouse and human non-lymphoid cells loose their cytoplasmic content of lambda light chains, a component of IgE produced by the myeloma parent. This loss of immunoglobulin content was observed regardless of the species origin (mouse or human) of the non-lymphoid partner cell, suggesting that the factors responsible for extinction of this differentiated function are not specific for a species. The kinetics of the loss of immunoglobulin content was essentially identical in the different experiments, since all myeloma X non-lymphoid cell heterokaryons were scored as negative after immunofluorescence staining for lambda chains 4-6 hr after infusion. Myeloma cells treated with inhibitors of protein synthesis (puromycin and cycloheximide) also lost their cytoplasmic content of immunoglobulin after 4 hr. These results indicate that the fusion of myeloma cells with non-lymphoid cells results in an immediate inhibition of immunoglobulin synthesis.
mesh_terms: D000818:Animals; D002459:Cell Fusion; D003513:Cycloheximide / Q000494:pharmacology; D005455:Fluorescent Antibody Technique; D006801:Humans; D006822:Hybrid Cells; D007073:Immunoglobulin E / Q000096:biosynthesis*; D007147:Immunoglobulin Light Chains / Q000096:biosynthesis*; D007146:Immunoglobulin lambda-Chains / Q000096:biosynthesis*; D051379:Mice; D009101:Multiple Myeloma; D011691:Puromycin / Q000494:pharmacology
chemical_list: D007147:Immunoglobulin Light Chains; D007146:Immunoglobulin lambda-Chains; D007073:Immunoglobulin E; D011691:Puromycin; D003513:Cycloheximide