Identification of CTLA-4-Positive Cells in the Human Tonsil
CTLA-4 (cytotoxic T-lymphocyte-associated protein 4) was originally defined as a T-lymphocyte antigen and was used as a target in cancer immunotherapy. Unfortunately, the existence of CTLA-4 in cells other than T-lymphocytes is often overlooked. The goal of the present study was to analyze the distribution pattern of CTLA-4 in the human tonsils using a panel of anti-CTLA-4 antibodies of different clones. We found that CTLA-4 was expressed in T-lymphocyte cells of various geneses, including hematopoietic cells and their derivatives (monocytes, macrophages, dendritic, plasma cells, mast cells, and neutrophils), as well as stromal cells of mesodermal (mesenchymal) origin and reticular epithelial cells of ectodermal origin. The expression of CTLA-4 in cells of different origins supports the proposition that CTLA-4 is not restricted to the lymphoid cell lineage and can provide broader effects of CTLA-4 on immune regulation.
1 Institute for HematopathologyHamburg 22547, Germany
2 Research and Educational Resource Center for Immunophenotyping, Digital Spatial Profiling and Ultrastructural Analysis Innovative Technologies, Peoples' Friendship University of RussiaMoscow 117198, Russian Federation
3 Research Institute of Experimental Biology and Medicine, Burdenko Voronezh State Medical University, Voronezh, 394036, Russian Federation