In article <43au50$56p at news.bu.edu>, alwang at bu.edu says...
>>Could anybody tell me what exactly are Natural Killer Cells?
> I need characteristics, how they differ from other white cells, and
>their specialty. Thank you.
As far as I'm aware (and I could be wrong), Natural Killer cells (NK cells) are
mediators of natural immunity. Which means that they don't require a specific
antigen-receptor interaction to kill, unlike cytotoxic T lymphocytes (CTLs). T
cells only recognize antigens attached to the major histocompatibility complex
(MHCs) on a cell surface. So NK cells are akin to primitive CTLs that lack the
specific T cell receptor (TCR) for antigen recognition. Thus, the target
specificity of NK cells is greater than that for CTLs. Furthermore, NK cells
are different from T and B cells in terms of surface markers. NK cells don't
under go thymic maturation (as do T cells).
Functionally, NK cells are a "first-line" defense mechanism against infection,
and do their work early in infection, giving time for the later CTL response to
kick in.
Hope this helps a bit,
Gary
PS. Check out "Cellular and Molecular Immunology" by Abul Abbas et al. for
more information...
--
+--------------+----------------------------------------------------------+
- Gary C. Pien - "Power without perception is spiritually useless, -
+--------------+ and therefore of no true value." -
-
- -
- Gary_Pien at brown.edu Box G -
- MD/PhD Program in Pathobiology Brown University -
- Brown University School of Medicine Providence, RI 02912 -
+-------------------------------------------------------------------------+
