The relationship between cholera toxin receptor and the Thy-1 antigen determinants.

The aim of the present study was to determine the relationship of the Thy-1 antigenic determinants to the cell surface ganglioside GM1. Exposure of either thymus or bone marrow cells to Thy-1 alloantiserum partially inhibited the binding of [125I]cholera toxin (CT) by the cells. Xenoantibodies to Thy-1 antigens failed to affect the binding of [125I]CT to mouse thymus cells. In the reverse experiments, treatment of either thymus cells or brain homogenate with CT did not alter their capacity to absorb Thy-1 allo- and xenoantibodies. It is concluded that GM1 ganglioside does not constitute a Thy-1 antigenic determinant.