False-colour transmission electron micrograph (TEM) of a single,activated cytotoxic ("killer") T-lymphocyte (left,a class of white blood cell) after delivering the "kiss of death" to its target cell. T-lymphocytes are involved in cell-mediated response to invasion of body by foreign microorganisms,notably viruses and some bacteria,which are protected from antibodies (secreted by B-lymphocytes) by their host cells. "Killer" T- cells recognize antigens on their target cell & bind to the surface membrane. Dark vesicles between 2 cells represent T-cell enzymes involved in the destruction of the target cell membrane | |
Lizenzart: | Lizenzpflichtig |
Credit: | Science Photo Library / Edelmann |
Bildgröße: | 4831 px × 3609 px |
Modell-Rechte: | nicht erforderlich |
Eigentums-Rechte: | nicht erforderlich |
Restrictions: |
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