Abstract
During the pregnancy of the human subject, the immunity of the mother is possibly suppressed. The possibility was studied by examining whether or not the number of the lymphocytes having Y-chronosomes increased during the lymphocytic blastoid transformation in the culture in which the lymphocytes from the mother was mixed with those from her male baby.
After normal delivery, blood samples were obtained from both the mother and the baby. The lymphocytes were separated from the blood by means of the Limphoprep's specific gravity centrifugation and the separated cells were floated in RPMI 1640 solutions at a proportion of 2.5x 106 cells/ml. Thus, two floating solutions were prepared, that is, the one containing the lymphocytes of the mother and the other having those from the baby. Then 0.2 ml was taken from each solution, and both of them were put in the same test tube for a mixed culture. After 72 hours, 0.1 μg colcemid was added to the test tube. After 3 hours following the addition, Y-chromosomes were examined and [8H] thymidine intake was studied. For comparison, similar studies were carried out, using the lymphocytes of male babies, in healthy non-pregnant women, as well as in cases with abnormal conditions such as threatened abortion, vomiting during pregnancy and uterus cancer.
(1) In the case of normal delivery, 86.3 5.9% of lymphocytes possessed Y-chromosomes. This indicates preponderant blastoid transformation of lymphocytes originating in the baby. In other words, the transformation of the lymphocytes originating in the mother was suppressed.
(2) A similar suppressive effect was also observed upon the lymphocytes of the mother who did not gave birth to the baby from whom the lymphocytes were obtained (65.1 6.9%).
(3) In the case of threatened abortion, a difference was observed between the cases with unfavourable prognosis and those with favourable prognosis. Namely, in the former case, the lymphocytes having Y-chromosomes were much less in number than in the latter case.
(4) In all cases studied, the mixed culture exhibited a high thymidine uptake alike.
