Leucocyte cultures of immunized rats and rabbits

Leucocytes of Wistar rats and white New Zealand rabbits were cultured following immunization with each of the ABO blood sera as well as with fetal calf serum. The rates of survival, transformation and mitosis varied with the type of agent used for immunization. Both macro- and micromethods were successful. The small amount of blood required by the micromethod makes it a feasible method for repetition of cytogenetic studies because it does not necessitate the sacrifice of the test animal.

Familial occurrence of trisomy 22

Images

Leucocyte cultures in five strains of mice

Leucocytes of five inbred strains of mice (LG, Swiss, SM, C3H and C57) were separated from whole blood by using 6% dextran and then grown in tissue culture medium in the presence of PHA and fetal calf serum. Transformation occurred in all strains, but mitotic divisions were observed only in the LG and Swiss strains at a maximum on the second day of culturing. The maximum mitotic index was 3.4% in both strains. The addition of human AB serum to the cultures increased the death rate of the cells and there was no mitosis.

Mail-order chromosome analysis

A simple but reliable technique has been developed for the mailing of plasma to chromosome laboratories for cytogenetic analysis. Cultures have been grown successfully from plasma which has been as long as four days in transit. Plasma is removed after heparinized whole blood has been left standing at room temperature for at least three hours. Phytohemagglutinin (0.1 ml. PHA/ml. plasma) and two to three drops of red cells are added to the plasma, and the specimen is immediately transmitted by air mail to the nearest cytogenetic laboratory. Sterile technique is used throughout.

A method for culturing leucocytes of rats and rabbits

Rats and rabbits were immunized with human AB serum or albumen. Leucocyte cultures were set up three to four weeks later. Numerous mitotic figures were obtained in cultures to which both phytohemagglutinin and human serum were added. No mitotic divisions were observed in non-immunized controls.