Erratum to: Induction of initial steps of angiogenic differentiation and maturation of endothelial cells by pericytes in vitro and the role of collagen IV

Erratum to: Histochem Cell Biol DOI 10.1007/s00418-015-1398-z

Unfortunately, Figs. 5 and 6 are interchanged in the available online version. Therefore, the figure linked to legend ‘Fig. 6’ represents Fig. 5 and is described in the text and legend as ‘Fig. 5’. Vice versa, the figure linked to legend ‘Fig. 5’ represents Fig. 6 and is described in the text and legend as ‘Fig. 6’.

The legend for Fig. 6 reads as: “Bar 100 μm. d An individual PVC is recruited to the endothelial tube in a region of extended collagen IV deposits”. The correct text is: “An individual PVC is recruited to the endothelial tube in a region of extended collagen IV deposits”.

We apologize for these errors.

The corrected Figs. 5 and 6 and their legends are given below.

Fig. 5

Pericyte-like vascular cells attach and proliferate differently on various ECM proteins, and integrin α1β1 mediates adhesion to collagen IV. a, b Attachment of PVC and HUVEC on surfaces coated with collagen I (Col1, 1.25–80 μg/ml) and IV (Col4, 0.15–10 μg/ml), fibronectin (FN, 0.15–10 μg/ml) and laminin 1 (LN-1, 1.25–80 μg/ml). c, d Adhesion of PVC and HUVEC to collagen IV (Col4; black) can be specifically blocked by neutralizing antibodies for integrin α1 (anti-α1), but not by anti-α2 or the IgG isotype control. Adhesion to fibronectin (FN; white) is not affected by any neutralizing antibody. Data are expressed as mean ± SD, n = 5

Fig. 6

Collagen IV is expressed by endothelial cells as extended networks, which contribute to PVC recruitment. Cocultures of HUVEC and PVC were immunostained for (a) collagen type IV (Col4, green) or b nidogen-1 (Nid1, green) in combination with CD31 (red), respectively. Tube-associated continuous matrix layers (open arrowhead) as well as an extended collagen IV mesh (filled arrowhead) can be seen, which is also decorated by nidogen-1. PVC (arrows) are indicated by the nuclear stain (blue) but do not express collagen IV. Bar 50 μm. c The mouse integrin α2 subunit (mIntegrin α2, red) is detected in PVC, which interact with forming tubes marked by collagen IV (Col4, green) and CD31 (magenta). An individual PVC is recruited to the endothelial tube in a region of extended collagen IV deposits. Bar 50 μm. Merged pictures include nuclear staining (blue)