A centrifugal technology is under development to produce liposomes from a nanoemulsion and to enable high encapsulation efficiencies in asymmetric membranes. Heparin complexes are used for a robust protective coating of liposomes. To enable in vitro and in vivo testing of liposomal formulations, mistletoe preparations with differences in viscotoxin (VT) and mistletoe (ML) lectin composition were tested on murine cell lines. A proliferation assay was performed to determine the half maximal inhibitory concentration (IC50) and select sensitive cell lines for in vivo experiments. abnobaVISCUM (AV) Pini preparations, with the lowest total ML content and a ML°III dominated composition, showed a stronger inhibition of proliferation on B16-F10 (mouse melanoma) cells relative to the total ML content compared to AV Fraxini and Quercus. ML I is the major cytotoxic component in AV Fraxini and AV Quercus and therefore a potential API for encapsulation in liposomes. The tested colon carcinoma cell line C26 is significantly more sensitive to isolated ML I than the aggressive B16-F10 melanoma cell line. In regard to animal models, this allows to co ... mehrmpare a sensitive to a relatively non-sensitive and more aggressive tumor cell line. In comparison to C26, the macrophage cell line RAW264.7 is relatively insensitive to isolated ML I, suggesting the possibility of selecting therapeutic concentrations that target e.g. colon tumours, but leave immune functions intact.