The application relates to a method of using compositions having anti-alpha-4 integrin andor anti-alpha-9 integrin activity to inhibit liquid tumor growth, malignancies thereof andor development of metastases thereof that involve expression of an alpha-4 integrin andor alpha-9 integrin. In particular, the invention relates to the field of industrial production of viral vectors and vaccines, more in particular to the use of avian embryonic stem cells, preferably the EBx\xae cell line derived from duck embryonic stem cells, for the production of viral vectors and viruses. The advantages of both the SIT structure and the insulated gate field effect transistor structure are obtained. The digital rate controller allows programmable control of the speed of the phase-locked loop.