In:
The Journal of Immunology, The American Association of Immunologists, Vol. 204, No. 1_Supplement ( 2020-05-01), p. 148.17-148.17
Abstract:
Natural killer (NK) cells are innate lymphoid cells that exert immediate functions which can be further augmented and sustained with immunostimulatory cytokines. Memory CD8 T cells, due to expression of CD132 and CD122, can be activated by similar cytokines in the absence of TCR engagement (termed “bystander” activation). This results in activation and proliferation but necessitates high amounts of cytokine as high-affinity IL2R complexes (CD25) are not induced. Interestingly, both cell types can then elicit similar effector functions via NKG2D-mediated target cell recognition. As these cell types can fill a similar immunologic niche, we set out to compare NK and memory CD8 T cell responses following IL-15 exposure in vitro from healthy human donors. Cell analysis was performed by flow cytometry and qRT-PCR. At baseline, CD25 expression is negligible at & lt;5% on both human NK and memory CD8 T cells. Surprisingly, culture with rhIL-15 (10 ng/mL) for 4–6 days resulted in marked CD25 upregulation on CD56+CD3− NK cells but not bystander-activated CD45RA-CD95+ CD8 T cells (72±9.2% vs 11±3.8%, P=0.003) despite comparable expansion. Additionally, cytokine-activated NK cells expressed higher levels of inhibitory receptor TIGIT (85±4% vs 57±2%, P=0.01) and activation marker CD69 (99±1% vs 27±9%, P=0.008). Functionally, NK cells had increased expression of granzyme B compared to bystander-activated CD8 T cells. Thus, although NK and bystander CD8 T cells can fill a similar immunologic niche regarding target cell killing, there are significant differences in expression of critical markers following activation. These differences may have consequences in the regulation of these cell types and impact anti-viral and anti-tumor responses.
Type of Medium:
Online Resource
ISSN:
0022-1767
,
1550-6606
DOI:
10.4049/jimmunol.204.Supp.148.17
Language:
English
Publisher:
The American Association of Immunologists
Publication Date:
2020
detail.hit.zdb_id:
1475085-5
