Fig. 3From: Modeling immune functions of the mouse blood–cerebrospinal fluid barrier in vitro: primary rather than immortalized mouse choroid plexus epithelial cells are suited to study immune cell migration across this brain barrierMorphology, expression of transthyretin and propagation of ECPC4 cells. Representative phase contrast pictures of ECPC4 cells from passage 41 on d1 (a) and d4 (b) after sub-cultured in a 1:4 ratio as described by the distributer. The cells did not show typical epithelial morphology (a, b) and grew in overlapping layers (b). Scale bars 50 μm. c Immunofluorescence staining for the CPEC-specific marker transthyretin (TTR) is shown in pmCPECs, Immortomouse® CPECs from passage 6, grown for 7 days at non-permissive conditions and for the ECPC4 cells. Scale bars a, b and ECPC4 cells = 50 μm; pmCPECs and Immortomouse® CPECs = 100 μmBack to article page