CROSS-REACTIVITY OF T-CELL 'HELPER' FUNCTION.

The cross-reactivity of heterologous erythrocytes was measured at the level of the B and the T cell. B cells produced antibody with restricted cross-reactivity as compared with the cross-reactivity of T cells, assayed by their ability to help B cells in a primary anti-sheep erythrocyte immune response. Helper function was maximally elicited with low antigen doses. The data suggest that the T-cell antigen receptors for erythrocyte antigens differ in specificity from those of B cells and that the sensitivity of T cells to antigen may be very great. [ABSTRACT FROM AUTHOR]