Fig. 4. Merkel cells are increased in K14-noggin and decreased in K14-BMP4 mice. Innervation to the mouth of whisker follicles in wild-type, K14-noggin and K14-BMP4 mice as shown by double-label immunofluorescence with anti-NF200 (Cy3) and anti-PGP (Cy2). e, epidermis at the mouth of a whisker follicle. A-D are from an Fvb background; E,F are from CB6F1 background. The broken line indicates the border between the epidermis and dermis. Green arrowheads indicate examples of FNEs in the epidermis which are labeled only with anti-PGP. Note that the epidermis of the K14-noggin mice contains far more FNEs and that the K14-BMP4 mice have fewer FNEs than their corresponding wild-type littermates. Yellow curved arrows indicate Merkel endings labeled with anti-NF200 and anti-PGP that terminate on Merkel cells (asterisks) labeled only with anti-PGP. Note that the Merkel cells and innervation are increased in K14-Nog and decreased in K14-BMP4 mice.