Expression of the janus kinases-signal transducers and activators of transcription pathway in Hassall's corpuscles of the human thymus

• Published in: Histochemistry and cell biology Vol. 113; no. 6; pp. 427 - 431
• Main Authors: Nishio, H, Matsui, K, Tsuji, H, Tamura, A, Suzuki, K
• Format: Journal Article
• Language: English
• Published: Germany Springer Nature B.V 01-06-2000
• Subjects: Child, Preschool; Corpuscles; DNA-Binding Proteins - analysis; Epithelium; Female; Humans; Immunohistochemistry; Infant; Infant, Newborn; Janus kinase; Janus Kinase 1; Janus Kinase 2; Localization; Male; Medulla oblongata; Phosphorylation; Protein-Tyrosine Kinases - analysis; Proteins - analysis; Proto-Oncogene Proteins; Signal transduction; Signal Transduction - physiology; Stat1 protein; STAT1 Transcription Factor; Stat2 protein; STAT2 Transcription Factor; Stat5 protein; Stat6 protein; STAT6 Transcription Factor; Thymus; Thymus Gland - chemistry; Thymus Gland - enzymology; Thymus Gland - ultrastructure; Trans-Activators - analysis; Transcription factors; Transcriptional Activation - physiology; Transformed cells; TYK2 Kinase; Tyk2 protein; Tyrosine - metabolism
• ISSN: 0948-6143; 1432-119X
• DOI: 10.1007/s004180000142

The janus kinases (JAK) and signal transducers and activators of transcription (STAT) pathway has been shown to play a key role in cytokine-mediated signal transduction, and to regulate growth, differentiation, and death of both normal and transformed cells. In the present study, we investigated immunohistochemically the distribution of the JAK-STAT pathway in the human thymus. Various elements of the pathway were abundantly expressed in Hassall's corpuscles, located in the thymus medulla and representing terminal stages of the thymic medullary epithelium. Furthermore, the elements of the pathway showed distinct localization in Hassall's corpuscles. JAK1, JAK2, and TYK2 were expressed in high amounts in the entirety of Hassall's corpuscles, whereas JAK3 was in the outer layer. STAT1, STAT2, and STAT6 were abundantly expressed in the entire Hassall's corpuscles, whereas STAT5 was in the outer layer. These findings strongly suggest that the JAK-STAT pathway may play a role in thymic medullary epithelial maturation.