Rosette formation of pig peripheral blood lymphocytes with sheep red blood cells.

Peripheral blood lymphocytes of normal young pigs formed spontaneous and EAC rosettes with sheep red blood cells. Pretreatment of the SRBC with a sulphydryl reagent increased the percentage of spontaneous rosettes and the number of SRBC bound by the lymphocytes. The influence of an incubation period prior to centrifugation and the duration and temperature of the following incubation were tested for spontaneous and EAC rosettes. The importance is stressed to define the number of bound SRBC to call a lymphocyte a "rosette-forming cell". Rosette formation is interpreted as a quantitative rather than a qualitative marker.