Natural Killer Cells – MCQ for Surgery & Immunology
Q) What are natural killer cells?
a) Multinuclear monocytes
b) Special macrophages
c) Antigen presenting cells
d) Large granular lymphocytes
Answer: d) Large granular lymphocytes
Natural killer cells are a part of lymphocytes called "null cells."
These are large granular lymphocytes and the first line of defence against viruses and bacteria.
They belong to null cells as they do not rely on specific match or memory.
NK cells control both tumor and microbial spread in the body.
Unlike T cells (which mature in thymus), natural killer cells develop in the bone marrow.
They identify viruses and other harmful cells by the lack of major histocompatibility complexes (MHC).
Antigen presenting cells are B cells.
T cells are direct cytotoxic cells.