Verification and characterisation of human digital Ruffini’s sensory corpuscles

• Published in: Journal of anatomy 2021-01, Vol.238 (1), p.13-19
• Main Authors: Cobo, Ramón, García‐Mesa, Yolanda, Cárcaba, Lucía, Martin‐Cruces, José, Feito, Jorge, García‐Suárez, Olivia, Cobo, Juan, García‐Piqueras, Jorge, Vega, José A.
• Format: Article
• Language: English
• Subjects: Adult; Aged; Aged, 80 and over; Antigens, CD34 - metabolism; Axons; CD34 antigen; Corpuscles; cutaneous sensory corpuscles; Female; Fingers; glabrous skin; Glial cells; Humans; Immunohistochemistry; Immunoreactivity; Male; Mechanoreceptors - metabolism; Middle Aged; Neuronal-glial interactions; Original Paper; Original Papers; Phosphopyruvate hydratase; Ruffini's corpuscles; S100 protein; S100 Proteins - metabolism; Skin; Skin - metabolism; Young Adult
• ISSN: 0021-8782; 1469-7580
• DOI: 10.1111/joa.13301

Ruffini's corpuscles are present as long fusiform encapsulated sensory structures in different tissues including the skin. Although physiological analyses strongly suggest their existence in glabrous digital skin, such localisation remains unconfirmed. Here, we have investigated the occurrence of typical Ruffini's corpuscles in 372 sections of human digital skin obtained from 186 subjects of both sexes and different ages (19–92 years). S100 protein, neuron‐specific enolase and neurofilament proteins were detected, and the basic immunohistochemical profile of these corpuscles was analysed. Fewer than 0.3 Ruffini's corpuscles/mm2 were detected, with density distribution across the fingers being F4 > F3 > F2 > F1 > F5 and absolute values being F2 > F1 > F3 > F4 > F5. Axons displayed neuron‐specific enolase immunoreactivity, glial cells forming the core contained S100 protein, and the capsule was positive for CD34 but not Glut1, demonstrating an endoneurial origin. Present results demonstrate the existence of Ruffini's corpuscles in human glabrous digital skin at very low densities. Moreover, the identified Ruffini's corpuscles share the basic immunohistochemical characteristics of other dermal sensory corpuscles. Typical Ruffini's corpuscles in human glabrous digital skin. Ax: axon; c: capsule; gc: glial core. The dermis contains sensory corpuscles that mediate tactile stimuli. Ruffini's corpuscles are fusiform type II slowly adapting low‐threshold sensors. This study confirms the existence of Ruffini's corpuscles in human digital skin. Human glabrous digital skin contains fewer than 0.3 Ruffini's corpuscles per mm2. Ruffini's corpuscles share the same immunohistochemical profile as other sensors.