Fecha de publicación: -- Fuente: WIPO "tomato" There is described a chimeric protein comprising a first peptide (for example ColE7 or a functional portion thereof) and first and second segments of a second peptide, wherein said second peptide includes an epitope from a target peptide. The target peptide is selected from the IL-6 family of cytokines. The second peptide is derived from a target peptide in which an N-terminal segment is transposed with a C-terminal segment. The epitope is available for binding by a separate binding partner, for example an antibody or a cell receptor.