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Updated: Jul 27, 2025
An Ex Vivo Chicken Primary Bursal-cell Culture Model to Study Infectious Bursal Disease Virus Pathogenesis
Published on: October 4, 2018
Appearance of Extrachromosomal Circular DNA in Lymphocytes from Developing Chick Bursa:
Masaaki Toda1, Hideo Yamagishi1
1Department of Biophysics, Faculty of Science, Kyoto University, Kyoto, Kyoto 606, Japan.
Abstract:
Lymphocytes were purified from the developing bursa of Fabricius of chick embryos and chickens and pressed with a mica sheet. Then the extruded DNA complexes were adsorbed to the mica and processed for electron microscopy. Circular DNA complexes were found at 40 to 60 copies in all bursal lymphocyte except 12-day-old embryonic bursas, which contained 150 copies. Circular DNA complexes of more than 1 μm (larger circular DNA) appeared in 12-day-old embryonic bursas at more than 20 copies per cell, and subsequently decreased in number to less than 10 copies per cell. These changes in the size distribution and copy number of circular DNA coincided with lymphocyte differentiation of the hemopoietic precursor cells in the bursa after seeding.
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