Abstract: Identifying subdominant/cryptic epitopes (I) that are presented by a HLA (human leukocyte antigen) Class I molecule, is new. Identifying subdominant/cryptic epitopes (I) that are presented by a HLA (human leukocyte antigen) Class I molecule comprising selecting at least one peptide (II) of 8-11 amino acids (aa), potentially representing an epitope for Class I presentation, from a protein against which a cytotoxic T cell (CTL) response is to be raised. (II) corresponds to a non-immunogenic peptide with low affinity for Class I molecules. Variants (IIa) of (II) are prepared in which the N-terminal aa is replaced by Tyr and their immunogenicity detected by identifying those that generate a CTL response against target cells expressing the parent protein. Peptide sequences from which active (IIa) are derived are then identified.

Abstract: Identifying subdominant/cryptic epitopes (I) that are presented by a HLA (human leukocyte antigen) Class I molecule, is new. Identifying subdominant/cryptic epitopes (I) that are presented by a HLA (human leukocyte antigen) Class I molecule comprising selecting at least one peptide (II) of 8-11 amino acids (aa), potentially representing an epitope for Class I presentation, from a protein against which a cytotoxic T cell (CTL) response is to be raised. (II) corresponds to a non-immunogenic peptide with low affinity for Class I molecules. Variants (IIa) of (II) are prepared in which the N-terminal aa is replaced by Tyr and their immunogenicity detected by identifying those that generate a CTL response against target cells expressing the parent protein. Peptide sequences from which active (IIa) are derived are then identified.

Abstract: A pharmaceutical composition comprising CD4+ CD25+ regulatory T cells specific for at least one minor histocompatibility antigen, and stem cells, advantageously haematopoietic, carrying at least the antigen can be used as a medicament for increasing the immune tolerance of a histocompatible host.