Identification of mouse H-2 antigens by mixed lymphocyte culture in the presence of PHA. I. Blastformation in the tissue culture of mouse lymph node cells in the presence of PHA

It is said blastformation can hardly be observed in the tissue culture of mouse lymphocytes. However, in our experiments of mouse lymphocytes (obtained either from axillary or cervical lymph nodes) mixed with various cells in combination of other cells as A+C3H, A+C57BL, or C3H+C57BL, it has been verified that these lymphocytes readily undergo blastformation in the presence of PHA (phytohemagglutinin M) as adjuvant. In the single tissue culture of these lymphocytes without PHA, the blastformation is observable in 6 per cent of the cells, while in the presence of PHA it is seen in 13. 7 per cent of the cells. In the cases of mixed cultures blastformation is observable in 14 per cent in the absence of PHA, whereas it is seen in 35.4 per cent in the presence of PHA. There is obviously a significant difference (p=O.OOI) in the blast. formation when cultured in the presence of PHA, and its reproducibility also proves to be quite high.