[Contact interaction of mast cells and lymphocytes during ontogenetic antigen-induced differentiation and malignant transformation of lymphoid cells].

Mastocytes of newborn rats as well as those of adult ones are capable of rosette-formation, whereas the ability of lymphocytes to from rosettes increases with age. The thymocytes of 3-month-old mice lose the ability to mastolymphocytic rosette-formation (MLR) after priming for one hour at 45 degrees C. The ability of thymocytes and splenocytes to MLR-formation is closely related to the time course of immunization of the animals and the method of immunization. The thymocytes and splenocytes of mice with leukemia show a decreased and increased ability to MLR-formation, respectively.