I wish to extend my sincere gratitude to all those who contributed to the success of this work and my sojourn in the Chair of Molecular Parasitology, Humboldt-University of Berlin.

I wish to thank Professor Dr. Richard Lucius for his supervision, moral support and for offering me the possibility to do my thesis at the Chair of Molecular Parastology.

I wish to thank Prof. Dr. Vincent P.K. Titanji and the members of his research team at the Biotechnology Unit, University of Buea for their support and cooperation.

My particular thanks go to Prof. Dr. W. Höhne and Dr. Rudolf Volkmer-Engert of Charité Medical faculty, Humboldt-University of Berlin for designing and synthesizing the synthetic peptides, respectively.

My thanks also go to Dr. Jörg Hirzmann (University of Gießen) for providing the A. viteae genomic library used in this study.

My sincere gratitude goes to Dr. Thomas Pogonka for the close supervision and for regular and helpful discussions on the progress of this work.

I thank the staff and students at the Chair of Molecular Parasitology Berlin, for their support and discussions. Karin Biermann, Grit Meusel and Bettina Sonenburg are particularly thanked for their help in animal experiments. Many thanks go to Smitha Pillai and Michal Sereda for their moral support and collaboration. My thanks go to Chris, Jörg, Florian, Oliver and Katja for their interest in the work.

I also wish to thank my friends and family. Cécile Barra, Aysun Kara and Sabrina Werl are thanked for reviving my down-trodden spirit.

My special gratitude goes to the German Academic Exchange Services (DAAD) for financing my stay and study, as well as Dr. Bernd Kalinna and Dr. Susanna Hartmann for employing me within the framework of their projects.