BACKGROUND: The present study has explored the localization and distribution of calcitonin gene-related peptide (CGRP)-immunoreactive (IR) nerve fibers in prurigo nodularis, especially emphasizing its relationships to mast cells and eosinophils, which all are important contributors to inflammation. METHODS: The exact localization of CGRP in the nerve fibers of prurigo nodularis lesional skin has been clarified by an ultrastructural immunogold labelling technique; and the relationships of CGRP-IR nerve fibers to tryptase-IR mast cells or eosinophil cationic protein (ECP)-IR eosinophils were also investigated by immunofluorescence double-labelling. RESULTS: This ultrastructural study has demonstrated that CGRP immunoreactivity is increased in the dense-core vesicles in the axons of the prurigo nodularis lesional skin; the axons which contain CGRP are, in addition, enlarged and have more dense-core vesicles than the axons which do not contain CGRP. The immunofluorescence investigation demonstrated that tryptase-containing mast cells and ECP-containing eosinophils also are significantly increased in the lesional skin. CONCLUSIONS: The results indicate that certain neurons increasingly express CGRP, which may dynamically result in a neurogenic inflammation in the lesional skin, through vasodilatation, and recruitment and regulation of inflammatory cells, e.g. eosinophils and mast cells.
BACKGROUND: The present study has explored the localization and distribution of calcitonin gene-related peptide (CGRP)-immunoreactive (IR) nerve fibers in prurigo nodularis, especially emphasizing its relationships to mast cells and eosinophils, which all are important contributors to inflammation. METHODS: The exact localization of CGRP in the nerve fibers of prurigo nodularis lesional skin has been clarified by an ultrastructural immunogold labelling technique; and the relationships of CGRP-IR nerve fibers to tryptase-IR mast cells or eosinophil cationic protein (ECP)-IR eosinophils were also investigated by immunofluorescence double-labelling. RESULTS: This ultrastructural study has demonstrated that CGRP immunoreactivity is increased in the dense-core vesicles in the axons of the prurigo nodularis lesional skin; the axons which contain CGRP are, in addition, enlarged and have more dense-core vesicles than the axons which do not contain CGRP. The immunofluorescence investigation demonstrated that tryptase-containing mast cells and ECP-containing eosinophils also are significantly increased in the lesional skin. CONCLUSIONS: The results indicate that certain neurons increasingly express CGRP, which may dynamically result in a neurogenic inflammation in the lesional skin, through vasodilatation, and recruitment and regulation of inflammatory cells, e.g. eosinophils and mast cells.
Authors: Micah Belzberg; Martin Prince Alphonse; Isabelle Brown; Kyle A Williams; Raveena Khanna; Byron Ho; Shannon Wongvibulsin; Thomas Pritchard; Youkyung Sophie Roh; Nishadh Sutaria; Justin Choi; Jaroslaw Jedrych; Andrew D Johnston; Kakali Sarkar; Chirag Vasavda; Jimmy Meixiong; Carly Dillen; Kent Bondesgaard; John F Paolini; Wei Chen; David Corcoran; Nicolas Devos; Madan M Kwatra; Anna L Chien; Nathan K Archer; Luis A Garza; Xinzhong Dong; Sewon Kang; Shawn G Kwatra Journal: J Invest Dermatol Date: 2021-03-23 Impact factor: 7.590