Neurochemical markers in human cutaneous Merkel cells. An immunohistochemical investigation.
Merkel cells (MCs) are specialized sensory cells widely distributed in the epithelia of vertebrates. A variable immunohistochemical pattern of neuronal and neurotransmitter markers has been demonstrated in MCs of several species including man. In the present study, we investigated the expression of neurochemical markers in a selected population of human cutaneous MCs by immunofluorescence. The structural neural proteins protein gene product 9.5 and neuron-specific enolase were found to be the most reliable markers for MC identification. Moreover, neurofilament immunoreactivity was shown in a small subset of epidermal MCs. Among the neurotransmitter markers, evidence for expression of calcitonin gene-related peptide, vasoactive intestinal polypeptide, peptide histidine isoleucine amide, neuropeptide Y, neurokinin A, galanin, substance P, somatostatin and phenylethanolamine N-methyltransferase was found. These immunoreactivities were highly variable as far as number of positive cells and staining intensity were concerned. The results indicate that a complex and heterogeneous immunophenotype can be expressed even within a homogeneous population of human MCs.
Fantini
F
F
Department of Neuroscience, Karolinska Institute, Stockholm, Sweden.
Johansson
O
O
D000328:Adult; D015415:Biomarkers; D004847:Epithelial Cells; D004848:Epithelium / Q000378:metabolism; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D009479:Neuropeptides / Q000378:metabolism*; D012867:Skin / Q000166:cytology / Q000378:metabolism*
D015415:Biomarkers; D009479:Neuropeptides