CCR9 AND CCR7 are overexpressed in CD4- CD8- thymocytes of myasthenia gravis patients.

Abstract

Chemokine CC motif receptors 9 and 7 (CCR9 and CCR7) play a major role in the migration of T-cell precursors to the thymus to initiate T thymopoiesis. However, their role in development of T-cells in myasthenia gravis (MG) patients has not been fully elucidated. Expression and distribution of CCR9+ and CCR7+ cells were detected by flow cytometry and immunofluorescence. Real-time polymerase chain reaction was used to check the adhesion molecules on CD4- CD8- double-negative (DN) thymocytes. CCR9 and CCR7 expression by DN thymocytes increased in the MG thymus; the levels of CCR9, CCR7, interleukin-7R mRNA increased, and CXCR4 levels decreased compared with levels in the non-MG thymus. More CCR7 and CCR9 double-positive (DP) thymocytes were gathered near the subcapsular region in MG thymus. Enhanced expression of CCR9 and CCR7 may complicate the differentiation of DP thymocytes from the DN stage in MG thymus. Muscle Nerve, 2016 Muscle Nerve 55: 84-90, 2017.