Cell-Mediated Immune Response in the Developing Dog

摘要

Purebred Beagle dog fetuses, on gestation day 45, had phytohemagglutinin (PHA) and mouse spleen cell (MSC) responsive cells in spleen but not in thymus. The PHA and MSC responses per 106 spleen cells were respectively unchanged and diminished by postnatal day 90. Thymus cells remained MSC-unresponsive to postnatal day 90; however, they became PHA-responsive (PHA+) on gestation day 50. PHA+ cells per 106 thymus cells increased to postnatal day 3 and declined by postnatal day 90. Their appearance in thymus correlated with the developing dog’s ability to reject a massive leukemia allotransplant and their concentration throughout thymus development correlated with the thymus lymphocyte peripheralization rat