%0 Journal Article
%T Origin and Regenerative Potential of Vertebrate Mechanoreceptor-Associated Stem Cells
%A Darius Widera
%A Stefan Hauser
%A Christian Kaltschmidt
%A Barbara Kaltschmidt
%J Anatomy Research International
%D 2012
%I Hindawi Publishing Corporation
%R 10.1155/2012/837626
%X Meissner corpuscles and Merkel cell neurite complexes are highly specialized mechanoreceptors present in the hairy and glabrous skin, as well as in different types of mucosa. Several reports suggest that after injury, such as after nerve crush, freeze injury, or dissection of the nerve, they are able to regenerate, particularly including reinnervation and repopulation of the mechanoreceptors by Schwann cells. However, little is known about mammalian cells responsible for these regenerative processes. Here we review cellular origin of this plasticity in the light of newly described adult neural crest-derived stem cell populations. We also discuss further potential multipotent stem cell populations with the ability to regenerate disrupted innervation and to functionally recover the mechanoreceptors. These capabilities are discussed as in context to cellularly reprogrammed Schwann cells and tissue resident adult mesenchymal stem cells. 1. Introduction Meissner corpuscles (MCs, also called tactile corpuscles) were first described in 1852 by the German physiologists Rudolf Wagner and Georg Meissner [1]. These are encapsulated, rapidly adapting mechanoreceptors responsible for sensing light touch on the skin. Recently, due to their immunocytochemical properties, it has been proposed that MC may also act as nociceptors [2]. They can be found within the dermis, beneath the basal layer of skin regions sensitive to light touch. Within the murine, rat and human palatal mucosa, MCs are located centrally within palatal ridges (rugae palatinae) and are often accompanied by Merkel cell-neurites [3] (see Figure 1(a)). Remarkably, an anterior-posterior gradient of Nestin-expressing cells within the rat palate could be identified (see Figure 2). In particular, numerous Nestin-positive MCs can be observed in the lamina propria of hard palate, whereas nearly no MCs are present in the soft palate. In humans, the number of MCs gradually decreases with age [4]. Figure 1: Anatomical localization of Meissner corpuscles (MCs) and Merkel cell-neurite complexes (MCN) within rodent hard palate. (a) MCs are located centrally within palatal rugae in the lamina propria, whereas MCN can be found within the basal layer. (b) Nestin expression within rat palatal MCs and adjacent to MCN. Cryosections of rat hard palate were stained with mouse anti-Nestin antibody (clone Rat401) followed by incubation with secondary Alexa555-coupled anti-mouse detection antibody. Confocal analysis revealed strong immunoreactivity in numerous cells within MCs and adjacent to MCN. Figure 2: Anterior-posterior
%U http://www.hindawi.com/journals/ari/2012/837626/