Rosette formation with goat erythrocytes. A marker for human T lymphocytes.

We demonstrate the use of goat erythrocytes in a rosette procedure for the classification of human lymphocytes. The population is almost perfectly overlapping with the lymphocytes which form rosettes with sheep red blood cells. 70·2 ± 7·5% of peripheral lymphocytes form rosettes with goat erythrocytes and less than 1% of these cells have surface immunoglobulins. Enrichment of goat rosette-forming cells results in a population with an increased percentage of both goat and sheep rosettes. This population retains activity to the T-cell mitogens Con A and PHA, while the cells depleted of goat rosettes have greatly diminished responses to these same mitogens. Tonsil and spleen lymphocytes form 50·2 ± 6·8% and 24% of goat rosettes respectively, while peripheral blood lymphocytes from patients with CLL rarely form goat rosettes. Cell lines maintained rosetted with goat cells in a parallel fashion to sheep cells. Thus T-cell lines, such as Molt-3, which form rosettes with SRBC also rosette with GRBC, while sheep rosette-negative lines, i.e. Molt-4, are negative for both erythrocytes. B-lymphoid cell lines were negative, as were several lymphoma cell lines. There was a slight variation in the binding of goat cells, depending on the source of the goat. Thus, as in sheep rosettes, some animals were better sources than others, although all the animals tested formed rosettes. Human lymphocytes are capable of binding goat red cells. The cells which bind to the erythrocytes seem identical to those binding sheep red blood cells, and should be considered as a T-cell population. Preliminary inhibition data suggests that the receptor on T cells is the very same structure for both erythrocytes.