Regarding NK cells, the false statement is:
Antibodies do not induce proliferation of NK cells. NK cells express CD3, CD16 & CD56 and also but less commonly CD2 & CD8 Null cells (NK cells & K cells): Null cells are a heterogeneous group of lymphocytes (non T and non B) called so because:Do not form E rosettes (test to T lymphocytes is negative)Lack of surface immunoglobulins (test to identify B lymphocytes is negative)Account for 5-10 % of circulating lymphocytesNK cells: are also called large granular lymphocytes as they are larger and has azurophilic granules (which are absent in both T and B lymphocytes)They are 1st line defence against neoplastic cells and virus-laden cellsThey cause direct cell lysis which is: not mediated by immune response and does not involve antigen-antibody responseTherefore capable of getting rid of non-sensitized organismsActivated to Lymphocytes activated killer cells (LAK) in presence of IL 2 but not by antibodyIdentified by detection of CD57 Killer cells: paicipate in cell destruction with aid of antibody eg: antibody dependent cell-mediated immunityMechanism: antibody binds to an antigenic determinant on the target cellK cells then attach to target cells by means of their Fc receptors and cell lysis results. Even here cell lysis proceeds without phagocytosisThey are CD16 positive (ref: Harrison's 18/e p1754)
It is activated by IL-2
Expresses CD3 receptor
It is a variant of large lymphocyte
There is antibody induced proliferation of NK cells
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