Rosette formation by peripheral lymphocytes. II. Inhibition of the phenomenon.

In a previous paper it had been shown that up to 40% of human peripheral lymphocytes will make rosettes with sheep red cells. In this study the inhibitory effect of antilymphocyte serum (ALS) and of certain other preparations on this rosette phenomenon is described. ALS was prepared in horses by injection of human peripheral lymphocytes and rosette-inhibiting, cytotoxic and agglutinating titres were determined during immunization.

Rosette formation by peripheral lymphocytes.

In preparations of human peripheral lymphocytes suspended in serum absorbed with sheep red cells, up to 30% of the lymphocytes may make rosettes with sheep erythrocytes. Washed lymphocytes suspended in Hanks' solution make many rosettes if tested without delay. Such lymphocytes rapidly lose their capacity to make rosettes, but it can be restored by adding the serum of man or of the horse, rabbit or guinea-pig.