Mechanosensitive Ion Channel-Related Proteins in Terminal Glial Cells of Human Meissner and Pacinian Corpuscles

Terminal glial cells (TGCs) are integral components of cutaneous end-organ com-plexes (CEOCs) and have traditionally been regarded as structural and trophic elements. However, increasing evidence suggests their involvement in mechanosensation and mechanotransduction. This study aimed to investigate the expression of mechanosensitive ion channel-related proteins in TGCs and axons of human Meissner and Pacinian cor-puscles from glabrous skin at different anatomical sites. Using immunohistochemistry and immunofluorescence, we analysed the distri-bution of ASICs, ENaC subunits, PIEZO channels, and TRP family members. Axonal terminals showed widespread expression of these proteins, including PIEZO1/2, ASIC2, TRPC6, and TRPV4, consistent with their role in mechanotransduction. In contrast, TGCs displayed a more restricted and heterogeneous profile. ASIC2 and TRPV4 were con-sistently detected in Meissner corpuscles, whereas PIEZO1/2 and TRPA1 showed site-dependent expression. In Pacinian corpuscles, TGCs were positive for ASIC2, PIE-ZO2, TRPA1, and TRPV4. Notably, TRPA1 expression in TGCs is reported here for the first time. These findings support the idea that TGCs may modulate mechanosensory input, although their functional role remains to be elucidated.