HUMAN LYMPHOID-T AND LYMPHOID-B CELLS - ELECTRON-MICROSCOPIC STUDY ON THYMOCYTES, PERIPHERAL-BLOOD LYMPHOCYTES, MITOGEN-STIMULATED CELLS AND LYMPHOID-CELL LINES

Human lymphoid cells were studied by electron microscopy to find any morphological difference between T and B cells. The T cell population generally contains a smaller amount of the rough endoplasmic reticulum than the B cell in various functional states, i.e. peripheral blood lymphocytes of normal individuals, mitogen-stimulated lymphoblasts and lymphoid cell lines. This may depend on greater need of the rough endoplasmic reticulum for immunoglobulin synthesis in B cells, even though T cells produce some soluble mediators. Other differences between T and B cells are as follows: (1) Peripheral blood T lymphocytes often have clustered dense granules, while granules containing parallel tubular structures are more frequently seen in B lymphocytes. (2) Cultured T cell lines usually exhibit a higher nuclear-cytoplasmic ratio and less prominent nucleoli than B cell lines. © 1979, International Society of Histology and Cytology. All rights reserved.