A current supply includes a current mirror arrangement having a feedback circuit. The housing includes a base plate and first and second sidewalls extending downwardly from two opposite edges of the base plate, respectively. When wire is positioned in the channels, the wire is wound around the inductor core, but insulated from the inductor core and the other turns of wire. An electric central tap is provided, between two adjacent coil portions, by which a sensor current, provided for determining an axial position of the armature, can be fed into a subset of the coil portions. Also disclosed and claimed are the inhibitors of stem cell proliferation. The invention also provides methods of making the immunogenic compositions, by combining an HIV antigen, an isolated nucleic acid molecule containing an immunostimulatory sequence and an adjuvant.