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Incoming links: Michael Edidin
In 1970 Larry Frye and Michael Edidin fused mouse C11D and human VA-2 cell lines with Sendai virus, forming heterokaryons. Suspensions were maintained in a shaking water bath at . Removed aliquots were stained by indirect immunofluorescence: antibodies against parental surface antigens, then differently fluorescent secondary antibodies. A Leitz Ortholux fluorescence microscope used a mercury lamp and color-selecting filters. Green mouse and red human surface patterns became intermixed.[ref]
The rapid intermixing of cell surface antigens after formation of mouse-human heterokaryons by Larry Frye and Michael Edidin. Frye and Edidin, The rapid intermixing of cell surface antigens after formation of mouse-human heterokaryons, pp. 319–325: Summary, Cell fusion, Fluorescent staining, Fluorescence microscopy, Table 1, time-course results
Same-species fusions tested antibody specificity; stable hybrid lines supplied a two-color control. Inhibitors of biological translation did not prevent mixing; lowering temperature inhibited it. These observations supported lateral redistribution over rapid synthesis. The authors could not conclusively exclude passage through cytoplasm and return. The readout compared populations, not trajectories of a continuously observed individual biological cell, and did not establish unrestricted motion of every membrane protein.[ref]
The rapid intermixing of cell surface antigens after formation of mouse-human heterokaryons by Larry Frye and Michael Edidin. pp. 324–331: specificity controls, inhibitor studies, temperature dependence and Discussion of mechanisms iii and iv
Separate time-point samples reveal changing surface distributions
. Original qualitative schematic of the mouse-human heterokaryon membrane-mixing experiment. Dot counts and shapes are illustrative; separate samples show distributions rather than individual trajectories or measured mixing curves. Details.
The decisive design idea is to begin with spatially distinguishable material. A uniformly labeled surface can look unchanged while its components move. Bringing together differently identifiable parental surfaces creates an initial pattern whose loss reveals redistribution; antibody specificity makes that loss interpretable. Membrane topology asks which side a part faces, whereas this experiment asks where it can move along that side.
Chapter 7 by Michael Edidin in The Legacy of Cell Fusion, pp. 101–114, published 8 August 1996 by Oxford University Press. This is a chapter authorship credit.
Publisher chapter record: academic.oup.com/book/51114/chapter/422115676
Cited passages: chapter author credit, publication date and first-person abstract, identifying Larry Frye as a graduate student in the author’s laboratory.
Publisher record: doi.org/10.1242/jcs.7.2.319
Inspected primary article transcriptions: paperity.org/p/46792324/the-rapid-intermixing-of-cell-surface-antigens-after-formation-of-mouse-human and www.scribd.com/document/281188634/Frye-and-Edidin-Paper
Cited passages: Summary and introduction; printed pp. 321–323, Cell fusion, Fluorescent staining, Table 1 and Fluorescence microscopy; pp. 324–325, specificity controls and Table 2; pp. 326–329, inhibitor and temperature studies; pp. 329–331, Discussion, mechanisms iii and iv. The authors distinguish population samples from individual trajectories and discuss intracellular relocation as an alternative that their observations do not conclusively exclude.