The autologous mixed lymphocyte reaction is not primarily due to xenoantigenic stimulation.

Autologous mixed lymphocyte reaction (AMLR) is an interesting in vitro system in which T lymphocytes proliferate when cultured with non-T cells from the same individual. Because this system has both memory and specificity and elicits help, suppression, cytotoxicity, and soluble mediators, it has been proposed that it reflects in vitro the complex interactions of the immunologic network as it operates in vivo. A recent study, however, has cast doubt on the significance of this reaction by implicating xenoantigens, present during separation and/or culture procedures (e.g., sheep red blood cells or fetal calf serum), in the proliferative response of T cells. This question is analyzed by performing AMLR studies with cells (from eight normal subjects) that were separated with and without the use of sheep erythrocytes, and incubated with either fetal calf serum on normal human AB serum. Results were similar in all circumstances and negate a primary role of xenoantigens in AMLR.