Correlation between morphological blastformation rate and functional 3H-thymidine uptake in mixed lymphocyte culture in the presence of PHA

By dividing at random 14 normal persons into 7 pairs of two individuals each, lymphocytes were isolated from their peripheral blood and taking one of the pairs as stimulating cells or antigens and the others as responding cells, mixed lymphocyte culture (MLC) was carried out. As for the method of MLC we used our MLC method of unidirectional mixed culture with a small amount of lymphocytes in additition of 1% (v /v) PHA.M and cultured for three days, and a widely used conventional method in which 3H.thymidine uptake was the parameter of the blastformation rate and cultured for seven days. In comparing the results of these two groups of MLC the data in six experiments out of the seven coincided. Namely, with 5x 104 cells each of stimulating cell group and responding cell group, it is possible to achieve satisfactory MLC, the culture can be done only for three days without requiring any special technique and the results can be readily evaluated. Therefore, MLC by our simple method would yield satisfactory results in clinics.