GERM-LINE CHIMERA PRODUCED BY TRANSFER OF CULTURED CHICK PRIMORDIAL GERM-CELLS

Intrinsic primordial germ cells (PGCs) from stage 27 (5-day-old) chick embryonic germinal ridges were cultured in vitro for a further 5 days , and shown to proliferate on stroma cells derived from the germinal r idge. To determine whether these cultured PGCs could colonize and cont ribute to the germ-line, PGCs were isolated by gentle pipetting, label ed with PKH26 fluorescent dye and injected into the blood stream of st age 17 (2.5-day-old) chick embryos. The recipient embryos were incubat ed until they reached stage 28. Thin sections of these embryos were an alysed by fluorescent confocal laser microscopy. These analyses showed that the labeled donor PGCs had migrated into the germinal ridges of the recipient embryos, and transplanted PGCs had undergone at least 3- 7 divisions. These results suggest that PGCs that had passed far beyon d the migration stage in vivo were still able to migrate, colonize and proliferate in recipient chick embryonic gonads.