Suitable vectors of use in the present invention include protein and peptide vectors such as antibodies, cell adhesion molecules such as L-selectin, RGD-peptides, PECAM and intergrin, vectors comprising cytokines/growth factors/peptide hormones and fragments thereof, streptavidin, bacterial fibronectin-binding proteins, Fc-part of antibodies, transferrin, streptokinase/tissue plasminogen activator