The heterogenization of tumour cells with tuberculin. I. The coupling of tuberculin to cell surfaces using con-A as ligand.

The introduction of an antigenic determinant strongly recognized by T cells on to a cell enhances the immune response to weak cellular antigens. Tuberculin (PPD) is a particularly suitable antigenic determinant for this purpose since it behaves in many ways as a 'T-cell hapten'. It has been found that direct chemical coupling of PPD to cell surfaces damages their antigenicity, but that this can be circumvented by coupling PPD to the lectin Concanavalin A and using this as the ligand for binding PPD to the cell. Techniques for preparing Con-A/PPD using little glutaraldehyde or SPDP as cross-linking agents are described.