Biomaterial Database

Occurrence of lymphohaemopoietic tissue in the meninges of the stingray Dasyatis akajei (Elasmobranchii, chondricthyes). 1988

A Chiba, and M Torroba, and Y Honma, and A G Zapata

Department of Biology, Nippon Dental University, Niigata, Japan.

The cytoarchitecture of the lymphohaemopoietic masses occurring in the "meninx primitiva" of the stingray Dasyatis akajei (Elasmobranchii, Chondricthyes) has been analyzed by light and scanning and transmission electron microscopy. Lymphohaemopoietic aggregates showing similar morphologies occurred along all the central nervous system, but they were more frequent in the telencephalon, diencephalon, and mesencephalon. In each aggregate, the granulopoietic tissue appeared in a fibroblastic stroma surrounding the large blood vessels, and the lymphoid components were present in a reticular network. Developing and mature eosinophils and heterophils--as well as lymphocytes, monocytes, macrophages, and plasma cells--are the main free cells present in these meningeal aggregates. The remarkable intimate association between macrophages and lymphoid cells to form close cell clusters suggests some immunological capacity for the meningeal lymphohaemopoietic tissue. According to their capacities, presence of lymphoid tissue, and histological organization, the meningeal lymphohemopoietic aggregates of Dasyatis akajei resemble other lymphomyeloid aggregates associated with cranium and choroid plexuses in Holocephali and Ganoidei. The phylogenetical relationships of these aggregates with mammalian bone marrow are discussed.

UI	MeSH Term	Description	Entries
D008221	Lymphoid Tissue	Specialized tissues that are components of the lymphatic system. They provide fixed locations within the body where a variety of LYMPHOCYTES can form, mature and multiply. The lymphoid tissues are connected by a network of LYMPHATIC VESSELS.	Lymphatic Tissue,Lymphatic Tissues,Lymphoid Tissues,Tissue, Lymphatic,Tissue, Lymphoid,Tissues, Lymphatic,Tissues, Lymphoid
D008578	Meninges	The three membranes that cover the BRAIN and the SPINAL CORD. They are the dura mater, the arachnoid, and the pia mater.
D008854	Microscopy, Electron	Microscopy using an electron beam, instead of light, to visualize the sample, thereby allowing much greater magnification. The interactions of ELECTRONS with specimens are used to provide information about the fine structure of that specimen. In TRANSMISSION ELECTRON MICROSCOPY the reactions of the electrons that are transmitted through the specimen are imaged. In SCANNING ELECTRON MICROSCOPY an electron beam falls at a non-normal angle on the specimen and the image is derived from the reactions occurring above the plane of the specimen.	Electron Microscopy
D002490	Central Nervous System	The main information-processing organs of the nervous system, consisting of the brain, spinal cord, and meninges.	Cerebrospinal Axis,Axi, Cerebrospinal,Axis, Cerebrospinal,Central Nervous Systems,Cerebrospinal Axi,Nervous System, Central,Nervous Systems, Central,Systems, Central Nervous
D005399	Fishes	A group of cold-blooded, aquatic vertebrates having gills, fins, a cartilaginous or bony endoskeleton, and elongated bodies covered with scales.
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia