• 1 January 1977
    • journal article
    • research article
    • Vol. 32  (4) , 467-474
Abstract
Cyclophosphamide-treated 18 day old chicken embryos were transplanted with histocompatible cells from the yolk sac at different stages of development and from the liver, thymus, bursa of Fabricius, spleen and bone marrow of 15 day old embryos. At the age of 36 days the cell recipients were studied to determine the reconstitution capacity of the transplanted cells. The parameters used include the survival pattern, gain of body weight, antibody-forming capacity, response of peripheral blood lymphocytes to Con A [concanavalin A], weight and microscopic morphology of the bursa of Fabricius, and weight of spleen and thymus. By all the criteria employed, only bursa cells were capable of a functional and morphological reconstitution of the recipient''s humoral immune system. The role of the yolk sac as the 1st generator of prebursal stem cells remains questionable. As a defferentiation site of the B[bone marrow-derived]-cell lineage, the bursa of Fabricius precedes the bone marrow during ontogenetic development.