Name: Felipe Campo, Antonio
Institution: Universitat de Barcelona
Center: Departament de Bioquímica i Biologia Molecular, Institut de Biomedicina.
Address: Av. Diagonal 645
Facultat de Biologia E-08028.
Phone: + 34 93-4034616
Fax: + 34 93-4021559
Our group is interested in the role of voltage-dependent K+ channels (Kv), mostly in the immunitary system. Kv channels control de leukocyte membrane potential and are involved in the proliferation and activation of lymphocytes and macrophages. Kv1.3 and Kv1.5 are the major Kv in these cells. While the role of Kv1.3 in the progression of many autoimmunitary diseases (multiple sclerosis, rheumatoid arthritis and diabetes) has been confirmed, the implication of Kv1.5 is not well understood. Unlike T-lymphocytes, macrophages express Kv1.5 and this channel co-associates with Kv1.3 generating the major Kv current in these cells. Different Kv1.3/Kv1.5 ratio generates a variety of multiple channels with different pharmacological and biophysical characteristics. Minor changes in the biophysical characteristics trigger major physiological and pharmacological consequences fine tuning the physiological responses. Mononuclear phagocytes are crucial in the immunitary response since they act as antigen presenting cells and influence in the surrounding milieu by producing cytokines and chemokines that activate target cells. This may generate a great variety of responses from proliferation to apoptosis. Kv1.3 is directly involved in all these processes; however the role of Kv1.5 is under controversy. We have described that the association of Kv1.3 and Kv1.5 triggers important biophysical and pharmacological changes in mononuclear phagocytes. The presence of Kv1.5 impairs the pharmacological response to Kv1.3-driven therapies, which are being developed to be used in human trials. Therefore the study of the Kv1.3/Kv1.5 regulation and association is of considerable interest to the further knowledge of the immunitary system physiology. Furthermore, these channels are associated to a number of known and unknown regulatory subunits. The identification of the proteins that further control the activity of the complex is a pivotal hallmark of our laboratory. Kv channels are located in specific domains at the cellular surface where they act as signalling molecules. The oligomeric structure of the functional complex influences traffic and targeting. Therefore, we also address considerable effort to the study of channel traffic and targeting, and how the oligomeric composition may alter the process and membrane localization.